Burr hole plug designs

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DESCRIPTION

Burr hole plug designs.

FIELD OF THE INVENTION

The present disclosure relates to an apparatus for securing elongated medical devices, such as catheters or wires, within a cranial trephine hole. The invention is set forth in the appended claims.

BACKGROUND OF THE INVENTION

Deep brain stimulation (DBS) and other related procedures that involve the implantation of electrical stimulus wires into a patient's brain are increasingly used to treat disorders such as Parkinson's disease, dystonia, tremor essential, epilepsy disorders, obesity, depression, restoration of motor control and other debilitating diseases by electrical stimulation through stimulation of one or more target sites, including the ventrolateral thalamus, internal segment of globus pallidus, pars reticulata substantia nigra, subthalamic nucleus (STN), or external segment of the pale balloon. DBS has become a prominent treatment option for many disorders because it is a safe and reversible alternative to injury. For example, DBS is the most frequently performed surgical procedure for the treatment of advanced Parkinson's disease. There have been approximately 30,000 patients worldwide who have undergone DBS surgery. Consequently, there is a large patient population who will benefit from advances in DBS treatment options.

During DBS procedures, at least one burr hole is meticulously cut through the patient's skull so as not to damage the brain tissue below, a large stereotactic targeting apparatus is mounted on the patient's skull, and a cannula is placed. scrupulously towards the target place in the brain. A stimulation lead is then introduced through the cannula, through the burr hole, and into the brain parenchyma, such that one or more electrodes located on the lead are strategically placed at a target site in the patient's brain. . Once the lead is properly positioned, the portion of the lead exiting the burr hole is routed subcutaneously under the patient's hair to an implantable pulse generator (IPG) implanted in the patient at a remote location. burr hole (for example, the patient's shoulder or chest region). More information explaining the treatment of diseases using DBS is described in US Patent No. 6,845,267, 6,845,267 and 6,950,707.

Significantly, proper lead placement and maintenance of lead position is crucial to continually achieving effective therapy. This is especially so with DBS applications, in which case the intended target site (s) for the electrical stimulus is approximately the size of a pea and is located deep within the patient's brain. Thus, cable displacements of less than one millimeter can have a deleterious effect on the patient's therapy. Therefore, it is important that the lead electrodes are accurately positioned at the target site and that such electrodes are held firmly at the target site during and after lead implantation. Additionally, it is important that the burr hole is sealed around the stimulation lead to prevent infection or spinal fluid leakage.

To address these issues, a cranial burr hole plug is installed within the burr hole during the implantation procedure to hold the stimulation lead in place as well as to seal the burr hole. Typically, the burr hole plug is comprised of a multitude of components, including a ring-shaped base, a retainer, and a cap, that are integrated together to form the burr hole plug.

In particular, before the stimulation wire is inserted through the burr hole, the plug ring shaped base is placed around the burr hole, and then permanently mounted on the patient's skull using conventional means, such as like screws. The stimulation wire is then introduced through the base of the plug and into the parenchyma of the brain. In particular, any displacement of the part of the wire that exits the burr hole will result in the translation of the electrodes placed in the brain with respect to the target site, thereby requiring the wire to be repositioned - a process that takes time. .

Thus, once the cable is properly positioned in the weaving site, the retainer is installed within the plug base (typically in an interference arrangement, such as a snap fit arrangement) to temporarily secure the plug. cable, thereby avoiding migration of the cable relative to the target site during subsequent manipulation of the proximal end of the cable and installation of the cap. In an exemplary embodiment, the retainer comprises a disc having a slot for receiving the cable and a clamping mechanism that can be rotated within the slot toward a mating surface on the disc to

ES 2 394 045 T3 gripping the cable received in between. The clamping mechanism may have one or more locking mechanisms that can be engaged or disengaged from complementary locking mechanisms on the disc to prevent rotation of the clamping mechanism. The portion of the stimulation wire exiting the retainer can then be bent down toward the plane of the disk into a recess formed in the plug base, and the cap can be installed over the plug base over the retainer to permanently secure the plug. wire into the recess as well as to seal the burr hole. More information regarding these types of burr hole plugs is described in US Patent Publication No. 2002/0156372.

Thus, from the foregoing it can be seen that the burr hole plug serves as a platform for the entire DBS system, and therefore it is important that this component is robust, well designed and easy to use. of using. Importantly, the burr hole plug should be designed in such a way that wire migration is minimized during the installation of the burr hole plug. While prior art burr hole plugs have proven useful in the context of DBS, improvements can still be made.

As an example, prior art burr hole plugs are typically comprised of non-corrosive, biocompatible material, such as a plastic (eg, polypropylene or polycarbonate), which, although less durable than other materials, is MRI-compatible and, unlike titanium, it will not distort the MRI. To ensure that the burr hole plug is sufficiently durable during installation within the burr hole, the plug base typically has a closed architecture (closed ring). Because of this, in addition to the position of the lead guide kit at the proximal end of the lead, the plug base must be mounted in or around the burr hole prior to delivery of the stimulation lead through the burr hole. While this, in itself, is not a problem, if the wire is inadvertently delivered into the patient's brain before the plug base is placed in the burr hole, the wire will need to be removed from the burr hole and the process cable delivery should be started again. Also, because prior art plug bases are made in one piece, there is a risk that the plug base may fracture if the plug base is anchored too tightly to the patient's skull, especially if the lower surface of the plug base does not coincide with the curvature of the skull.

Because the retainer installed within the plug base is also comprised of plastic material, the retainer will typically deform somewhat during installation within the plug base and during manipulation of the clamping mechanism to stabilize the cable. Furthermore, because the clamping mechanism will deform somewhat along its length when clamped against the stimulation lead, the clamping mechanism may apply uneven force, thereby weakening the holding force applied to the lead. Also, because of the relatively weak composition of the retainer, the clamping force between it and the mating surface of the disc is limited, thereby limiting the main clamping force of the clamping mechanism. Also, because a downward force is typically needed to unlock and allow the clamping mechanism to rotate relative to the disc, such a downward force can cause the clamping mechanism to bend too far downward, permanently deforming it out of place. that way or breaking it. Furthermore, since burr hole plugs are typically made up of biocompatible polymers that are very lubricious, especially when wet, the coefficient of friction of the retention surface of the clamping mechanism, as well as the mating surface of the disc, can be relatively short. As a result, the cable can go away when only a moderate amount of tension force is applied to it.

As another example of a problem suffered by prior art burr hole plugs, the retainer can rotate within the plug base, potentially resulting in inadvertent movement of the stimulation lead from the target site. Such rotation of the retainer mechanism can typically occur in response to manipulation of the retainer mechanism, and, in particular, a downward force applied to the retainer mechanism that causes partial disengagement between the retainer disc on which the mechanism is mounted. clamping and plug base, and a lateral force applied to the clamping mechanism that causes the disengaged disc to rotate within the plug base.

As yet another example, many DBS systems have evolved from a single-wire (one-sided) system to two-sided (two-sided) systems; for example, one lead is used to perform STN stimulation, while another lead is used to perform thalamic stimulation. Other DBS systems can use a recording cable to record brain signals that are then sent back to the IPG to control the stimulation applied to the target site by the stimulation cables. However, prior art burr hole plugs are not designed to stabilize more than one pacing lead at the same time. This is because the groove inside the disk can only secure wires that exit the burr hole along the diameter of the disk, even though the wires may be offset from the diameter. Thus, despite the fact that the target sites stimulated and / or etched by the leads may be close together, when multiple stimulation leads are used, multiple burr holes are typically formed in the patient's skull, each giving accommodates a stimulation lead and burr hole plug. By creating multiple burr holes, the risk to the patient, the time in the operating room (which also increases the risk to the patient), the materials and personnel needed in the operating room, and the cost of the procedure increase everyone so

ES 2 394 045 T3 a burr hole plug that can accommodate multiple cables through one burr hole is preferred.

As yet another example, it is preferable that the portion of the stimulation wire that exits the burr hole is arranged at an angle perpendicular to the length of the retaining disc groove when bent down into the plane of the disc, so that the cable does not move along the groove when it is tensioned. However, because the recess in the plug base in which the cable sits may be located obliquely (as opposed to perpendicular) to the slot, it can be difficult to bend the cable perpendicular to the slot into the recess of base if the cable support mechanism is not oriented perfectly with respect to the plug base. Furthermore, rotation of the cable support mechanism with respect to the base while the cable is seated within the base recess can cause the cable to be displaced from the target location.

In yet another example, the plug base must be held firmly in place while being anchored to the skull with screws. The retainer must also be mounted within the plug base, such that the retention disk properly seats within the plug base without disturbing the position of the cable, which is precariously supported by the stereotactic targeting apparatus. However, due to the minute size of the burr hole plug components, they are difficult to place, handle and handle. This, in combination with the limited working space between the aiming apparatus and the burr hole, makes it quite difficult to correctly visualize and install the plug within the burr hole and stabilize the wire. While the surgeon installs the burr hole plug components, there is a risk of foreign objects (screws, tools, dirt, etc.) falling into the exposed burr hole, as well as sliding of tools into the burr hole. . Prior art tools can be used, stabilizing the plug bases while covering the burr hole and holding / aligning the screws used to anchor the plug bases. However, the screws often pop out of these tools inadvertently and don't always thread into the skull at the correct angle.

Thus, the installation of the burr hole plug, without disturbing the position of the wire, is an almost impossible task without a specialization of the tools and / or the burr hole plug can center the plug base while it is anchored to the skull of the patient and hold and firmly mount the retainer on the plug base. Typically, the surgeon can use a special tool that is attached to the retainer, such that it can be directed and positioned within the plug base, and then be pressed down to snap fit into the plug base. However, this installation tool only attaches the retention disk in one location. In this way, it is possible that the disc could become twisted or tilted when trying to install it within the plug base, or even worse, receiving the spring force stored in the disc, it can be thrown from the surgical site.

In yet another example, prior art burr hole plugs are designed to be used with stimulation leads that are one size. That is, the dimension between the retaining surface of the fastener and the mating surface of the disc when the fastener is in the locked position is designed to be slightly less than the diameter of the cable. If the diameter of the true wire used with the burr hole plug is smaller than intended, the holding force applied to the wire by the clamping mechanism will not be sufficient. If the diameter of the true wire used with the burr hole plug is greater than this intended diameter, it will be necessary to apply too much force to the wire to bring the clamping mechanism into the locked position, potentially damaging the retainer and / or the wire.

As yet another example, once the plug base is mounted to the patient's skull by screws, it is difficult to adjust the position of the plug base if desired. Also, due to the relatively large size of the stereotactic targeting apparatus, there is often little working space available between the targeting apparatus and the burr hole to anchor the plug base to the skull of the patient.

Thus, there is still a need for improved burr hole plug designs.

SUMMARY OF THE INVENTION

The invention is set forth in the appended claims. The embodiment of the present description that does not fall within the scope of said claims is provided for illustrative purposes only and does not form part of the present invention. In accordance with the present invention, a burr hole skull plug is provided. The burr hole plug comprises a plug base configured to be mounted around a skull burr hole. The plug base includes an opening through which an elongated medical device exiting the burr hole can pass. The plug base opening has a suitable shape (for example circular) and a suitable dimension (for example equal to or less than 25mm). In one embodiment, the plug base includes an open slot configured to laterally receive the medical device.

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The burr hole plug further comprises a retainer configured to be mounted within the opening of the plug base to secure the medical device. In one embodiment, the retainer is configured to be removably mounted within the opening of the plug base. In another embodiment, the plug base includes at least one annular inner boss configured to support the retainer when mounted within the opening of the plug base. In yet another embodiment, the retainer further includes a retainer bracket (eg, a disk), a slot formed in the retainer bracket to receive the medical device, and a clamping mechanism configured to apply a clamping force to the medical device. received inside the slot. The clamping mechanism may include a clamping bar configured to engage the medical device, and a locking element configured to lock the clamping bar relative to the retainer bracket when the medical device is secured.

The burr hole plug may comprise other components in addition to the plug base and the retainer. For example, the burr hole plug may comprise fasteners configured to anchor the plug base to the skull of a patient, and a cap configured to be mounted to the plug base over the retainer. The plug base may have an outlet groove configured to seat the medical device, in which case the cap may be configured to firmly secure the medical device within the outlet groove when the cap is mounted on the plug base.

According to the present description, a method is provided for performing a medical procedure on a patient. The method comprises introducing an elongated medical device (eg, an electrical wire) through a cranial trephine hole of the patient and into the brain tissue of the patient. The method further comprises mounting a plug base around a cranial trephine hole such that the medical device extends through an opening in the plug base. In one method, the plug base includes an open slot, in which case the method may further comprise laterally inserting the medical device into the slot. In this case, the plug base can be mounted around the cranial burr hole after the medical device is inserted through the burr hole into the brain tissue of the patient. The method further comprises mounting a retainer within the opening of the plug base, and actuating the retainer to secure the medical device.

The following articles are preferred embodiments of the invention.

1. A trephine hole plug, comprising:

a plug base that includes a flange configured to be mounted around a cranial burr hole, an opening through which an elongated medical device exiting the burr hole can pass, and a plurality of tabs configured to extend into the cranial hole trephine for centering the plug base with respect to the cranial trephine hole; and a retainer configured to be mounted within the opening of the cap base to secure the medical device.

2. The burr hole plug of article 1, wherein the opening of the plug base is circular.

3. The burr hole plug of item 1, wherein the largest dimension of the opening is equal to or less than 25mm.

Four. The burr hole plug of article 1, wherein the plug base includes an open slot configured to laterally receive the medical device.

5. The burr hole plug of article 1, wherein the plurality of tabs comprises at least three tabs.

6. The burr hole plug of item 1, wherein the tabs are disposed on a lower surface of the plug base flange.

7. The burr hole plug of item 1, wherein the tabs are coincident with the opening.

8. The burr hole plug of item 1, wherein the retainer is configured to be removably mounted within the opening of the plug base.

9. The burr hole plug of article 1, wherein the plug base includes at least one annular inner boss configured to support the retainer when mounted within the opening of the plug base.

10. The burr hole plug of article 1, wherein the retainer further includes a retainer bracket and a slot formed in the retainer bracket for receiving the medical device.

ES 2 394 045 T3

eleven. The burr hole plug of item 10, wherein the retainer includes a clamping mechanism configured to apply a clamping force to the medical device received within the slot.

12. The burr hole plug of item 11, wherein a clamping mechanism includes a clamping bar, configured to engage the medical device, and a locking element, configured to lock the clamping bar relative to the retainer bracket when the medical device is insured.

13. The burr hole plug of article 10, wherein the retainer bracket is a disc.

14. The burr hole plug of article 1, further comprising fasteners configured to anchor the plug base to a skull of a patient.

fifteen. The burr hole plug of item 1, further comprising a cap configured to be mounted to the plug base over the retainer.

16. The burr hole plug of item 14, wherein the plug base has an outlet groove configured to seat the medical device, and wherein the cap is configured to firmly secure the medical device within the outlet groove when the cap is mounted on plug base.

17. A method of performing a medical procedure on a patient, comprising:

providing a plug base that includes a rim, an opening, and a plurality of tabs; positioning a plug base within a cranial burr hole, such that the flange is disposed around the cranial burr hole, and the tabs are arranged within the cranial burr hole to center the plug base with respect to the cranial burr hole. trepan;

anchoring the plug base with respect to the cranial burr hole;

introducing an elongated medical device through the cranial burr hole and into the brain tissue of the patient where the medical device exits the cranial burr hole through the opening in the plug base;

mounting a retainer within the opening of the plug base; and actuating the retainer to secure the medical device.

18. The method of item 17, wherein the flanges are equally spaced around the circumference of the cranial burr hole.

19. The method of item 17, wherein the tabs are disposed on a lower surface of the plug base flange.

twenty. The method of article 17, wherein the medical device is an electrical cord.

twenty-one. The method of article 17, wherein the plug base includes an open slot shape in the plug base rim, the method further comprises laterally inserting the medical device into the slot.

22. The method of item 21, wherein the plug base is mounted around the cranial burr hole after the medical device is inserted through the burr hole into the patient's brain tissue

2. 3. The method of item 17, further comprising mounting a cap to the plug base over the retainer.

24. A trephine hole plug, comprising:

a plug base including a flange configured to be mounted around a cranial trephine hole, and an opening through which an elongated medical device exiting the trephine hole can pass; and a retainer configured to be mounted within the opening of the plug base to secure the medical device, such that the retainer is at least partially recessed within the burr hole.

25. The burr hole plug of article 24, wherein the opening of the plug base is circular.

26. The burr hole plug of article 24, wherein the largest dimension of the opening is equal to or less than 25mm.

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27. The burr hole plug of article 24, wherein the plug base includes an open slot configured to laterally receive the medical device.

28. The burr hole plug of article 24, wherein the flange has a bottom surface and the retainer is configured to extend below the bottom surface of the flange.

29. The burr hole plug of article 24, wherein the plug base includes a plurality of tabs configured to extend into the skull burr hole to center the plug base with respect to the skull burr hole.

30. The burr hole plug of item 29, wherein the tabs are disposed on a lower surface of the plug base flange.

31. The burr hole plug of item 29, wherein the tabs are coincident with the opening.

32. The burr hole plug of item 24, wherein the retainer is configured to be removably mounted within the opening of the plug base.

33. The burr hole plug of article 24, wherein the plug base includes at least one annular inner boss configured to support the retainer when mounted within the opening of the plug base.

3. 4. The burr hole plug of item 33, wherein the plug base includes at least one annular rim extending from the at least one annular inner boss below a lower surface of the rim.

35. The burr hole plug of article 24, wherein the retainer further includes a retainer bracket and a slot formed in the retainer bracket to receive the medical device.

36. The burr hole plug of article 35, wherein the retainer includes a clamping mechanism configured to apply a clamping force to the medical device received within the slot.

37. The burr hole plug of item 36, wherein a clamping mechanism includes a clamping bar, configured to engage the medical device, and a locking member, configured to lock the clamping bar relative to the retainer bracket when the medical device is insured.

38. The burr hole plug of article 35, wherein the retainer bracket is a disc.

39. The burr hole plug of article 24, further comprising fasteners configured to anchor the plug base to a skull of a patient.

40. The burr hole plug of article 24, further comprising a cap configured to be mounted to the plug base over the retainer.

41. The burr hole plug of item 40, wherein the plug base has an outlet groove configured to seat the medical device, and wherein the cap is configured to firmly secure the medical device within the outlet groove when the cap is mounted on plug base.

42. A method of performing a medical procedure on a patient, comprising:

mounting a plug base around the cranial burr hole, the plug base includes a flange and an opening;

introducing an elongated medical device through the cranial burr hole and into the brain tissue of the patient where the medical device exits the cranial burr hole through the opening in the plug base;

mounting a retainer within the opening of the plug base such that the retainer is at least partially recessed within the burr hole; and actuating the retainer to secure the medical device.

43. The method of article 42, wherein the medical device is an electrical cord.

44. The method of article 42, wherein the plug base includes a groove shape in the plug base rim, the method further comprises laterally inserting the medical device into the groove.

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Four. Five. The method of item 44, wherein the plug base is mounted around the cranial burr hole after the medical device is inserted through the burr hole into the patient's brain tissue

46. The method of item 42, further comprising mounting a cap to the plug base over the retainer.

47. A trephine hole plug, comprising:

a split plug base configured to be mounted around a cranial burr hole, the plug base includes an opening through which an elongated medical device exiting the burr hole can pass, and a plurality of base parts configured to be unpaired with each other to separate the plug base, and to be paired with each other to integrate the plug base; including;

a retainer configured to be mounted within the cap base opening to secure the medical device.

48. The burr hole plug of article 47, wherein the opening of the plug base is circular.

49. The burr hole plug of article 47, wherein the largest dimension of the opening is equal to or less than 25mm.

fifty. The burr hole plug of article 47, wherein the plurality of base parts comprises only two base parts.

51. The burr hole plug of article 47, wherein each of the base parts is annular.

52. The burr hole plug of item 47, wherein the base portions are configured to mate together in an interference arrangement.

53. The burr hole plug of item 47, wherein one of the base parts has a recess, and another of the base parts has a protrusion configured to be positioned within the recess to match the base parts together.

54. The burr hole plug of article 53, wherein the recess is provided on an upper surface of the one base part, and the protrusion extends laterally from the other base part.

55. The burr hole plug of article 47, wherein the plug base comprises at least one element that firmly engages the base parts together.

56. The burr hole plug of item 55, wherein the at least one element is configured to be skewed after the base portions are unpaired from each other.

57. The burr hole plug of item 47, wherein the retainer is configured to be removably mounted within the opening of the plug base.

58. The burr hole plug of article 47, wherein the plug base includes at least one annular inner boss configured to support the retainer when mounted within the opening of the plug base.

59. The burr hole plug of article 47, wherein the retainer further includes a retainer bracket and a slot formed in the retainer bracket to receive the medical device.

60. The burr hole plug of item 59, wherein the retainer includes a clamping mechanism configured to apply a clamping force to the medical device received within the slot.

61. The burr hole plug of item 60, wherein a clamping mechanism includes a clamping bar, configured to engage the medical device, and a locking element, configured to lock the clamping bar relative to the retainer bracket when the medical device is insured.

62. The burr hole plug of item 59, wherein the retainer bracket is a disc.

63. The burr hole plug of article 47, further comprising fasteners configured to anchor the plug base to a skull of a patient.

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64. The burr hole plug of item 47, further comprising a cap configured to be mounted to the plug base over the retainer.

65. The burr hole plug of item 64, wherein the plug base has an outlet groove configured to seat the medical device, and wherein the cap is configured to firmly secure the medical device within the outlet groove when the cap is mounted on the plug base.

66. A method of performing a medical procedure on a patient, comprising:

inserting an elongated medical device through a patient's cranial trephine hole and into the patient's brain tissue, where an exposed portion of the medical device exits the cranial trephine hole, locating a first plug base portion adjacent to one side of the exposed part of the medical device; locating a second plug base portion adjacent to another side of the exposed portion of the medical device;

mating the first and second cap base portions together to form a cap base with an opening through which the exposed portion of the medical device extends;

mount the plug base around the cranial trephine hole;

mounting a retainer within the opening of the plug base; and actuating the retainer to secure the medical device.

67. The method of article 66, wherein the medical device is an electrical cord.

68. The method of article 66, further comprising anchoring the plug base in the skull of the patient.

69. The method of article 66, wherein the first and second plug base portions are paired together while the first plug base portion is positioned on one side of the cranial burr hole.

70. The method of article 66, wherein the first and second plug base portions are paired together by arranging the second plug base portion on the first plug base portion.

71. The method of article 66, wherein the first and second plug base portions are paired together in an interference arrangement.

72. The method of item 66, further comprising mounting a cap to the plug base over the retainer.

73. A trephine hole plug, comprising:

a plug base configured to be mounted around a cranial burr hole, the plug base includes an opening through which an elongated medical device exiting the burr hole can pass; and a retainer configured to be mounted within the opening of the plug base, the retainer includes a retainer bracket, a slot formed in the retainer bracket to receive the medical device, and a clamping mechanism having a clamping bar and a sliding flange slidingly engaged with the retainer bracket to laterally slide the clamping bar to secure the received medical device within the slot.

74. The burr hole plug of article 73, wherein the opening of the plug base is circular.

75. The burr hole plug of item 73, wherein the largest dimension of the opening is equal to or less than 25mm.

76. The burr hole plug of item 73, wherein the retainer is configured to be removably mounted within the opening of the plug base.

77. The burr hole plug of item 73, wherein the plug base includes at least one annular inner boss configured to support the retainer when mounted within the opening of the plug base.

78. The burr hole plug of item 73, wherein the retainer bracket is a disc.

79. The burr hole plug of item 73, wherein the retainer includes a recess formed in the retainer bracket along which the sliding flange slidably engages.

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80. The burr hole plug of item 79 wherein the retainer includes a pair of C-channels disposed on opposite sides of the recess, wherein a pair of opposite edges of the sliding lip are respectively received within the C-channels.

81. The burr hole plug of item 73, wherein the clamping bar has a clamping surface with relief characteristics.

82. The burr hole plug of item 73, wherein the slot is an open slot configured to laterally receive the medical device.

83. The burr hole plug of item 73, wherein the retainer bracket includes a first and a second part, and the retainer further includes a hinge coupled to the first and second part of the flange, whereby the first and second rim portion can alternately hinge open to laterally receive the medical cable within the slot and hinge close to surround the medical cable within the slot

84. The burr hole plug of item 73, wherein the retainer bracket has a fixed clamping bar on one side of the slot in front of the clamping bar, and the clamping bar is configured to clamp the medical cable against the bar fixed clamping.

85. The burr hole plug of item 73, wherein the clamping mechanism has a locking element configured to lock the clamp bar relative to the retainer bracket when the medical device is secured.

86. The burr hole plug of item 85, wherein the retainer bracket has a complementary locking element with which the locking element of the clamping mechanism is configured for engagement.

87. The burr hole plug of item 86, wherein the clamping mechanism has a resilient arm in which the locking element is disposed, and the arm is configured to be actively flexed to release the locking element from the complementary element

88. The burr hole plug of item 87, wherein the locking element is a flange and the complementary locking mechanism is an obstacle, the clamping mechanism is configured to be placed in a locked position by the flange abutting against the obstacle and the clamping mechanism is configured to be placed in an unlocked position by flexing the arm to release the flange from the obstacle.

89. The burr hole plug of item 88, wherein the flange and obstacle have abutting surfaces that are angled relative to a plane of the rim.

90. The burr hole plug of item 87, wherein the clamping mechanism has a recess configured to receive the tip of a tool to flex the arm resiliently.

91. The burr hole plug of item 90, wherein the recess is angled with respect to a plane of the retainer bracket such that a portion of a downward force applied to the recess is transferred in a direction away from the groove along the along the plane of the retainer bracket.

92. The burr hole plug of item 90, wherein the recess is located closer to a center of the retainer bracket than a circumference of the retainer bracket

93. The burr hole plug of article 87, wherein the clamping mechanism comprises an obstacle attached to the sliding flange, the obstacle is configured to limit flexure of the arm with resilience.

94. The burr hole plug of item 85, wherein the retainer bracket has a plurality of complementary locking mechanisms with which the locking element of the clamping mechanism is configured to selectively engage, such that the locking bar The clamp is configured to be locked relative to the retainer bracket at different positions.

95. The burr hole plug of item 73, further comprising fasteners configured to anchor the plug base to a skull of a patient.

96. The burr hole plug of item 73, further comprising a cap configured to be mounted to the plug base over the retainer.

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97. The burr hole plug of item 96, wherein the plug base has an outlet groove configured to seat the medical device, and wherein the cap is configured to firmly secure the medical device within the outlet groove when the cap is mounted on plug base.

98. A method of performing a medical procedure on a patient, comprising:

introducing an elongated medical device through a cranial trephine hole of the patient and into the brain tissue of the patient;

mounting a plug base around the cranial burr hole such that the medical device extends through an opening in the plug base;

mounting a retainer within the opening of the plug base, the retainer including a retainer bracket, a groove formed in the retainer bracket, and a clamping mechanism having a clamping bar and sliding flange slidably engaged with the retainer bracket; receive the medical device in the slot; and sliding the sliding lip relative to the retainer bracket to laterally slide the clamp bar, thereby securing the received medical device within the slot.

99. The method of article 98, wherein the medical device is an electrical cord.

100. The method of article 98, wherein the medical device is laterally received within the slot.

101. The method of article 98, wherein the retainer bracket has a fixed clamping bar on a side of the slot opposite the clamping bar, and the clamping bar clamps the medical cable against the fixed clamping bar.

102. The method of article 98, wherein the clamping mechanism has a locking member, and the method further comprises operating the locking member to lock the retainer bar with respect to the retainer bracket when the medical device is secured.

103. The method of item 102, further comprising actuating the locking member to unlock the clamp bar from the retainer bracket when the medical device is secured.

104. The method of item 103, wherein the clamping mechanism has a resilient arm in which a locking member is provided, and the method comprises actively flexing the resilient arm to actuate the locking member to unlock the retainer bar. with respect to the retainer bracket when the medical device is secured.

105. The method of item 102, further comprising operating the locking member to lock the clamp bar in different positions.

106. The method of item 98, further comprising mounting a cap to the plug base over the retainer.

107. A trephine hole plug, comprising:

a plug base configured to be mounted around a cranial burr hole, the plug base includes an opening through which an elongated medical device exiting the burr hole can pass; and a retainer configured to be mounted within the opening of the cap base to secure the medical device, the retainer includes at least one outlet groove configured to seat the medical device, such that the medical device is directed radially toward the plug base.

108. The burr hole plug of item 107, wherein the opening of the plug base is circular.

109. The burr hole plug of item 107, wherein the largest dimension of the opening is equal to or less than 25mm.

110. The burr hole plug of item 107, further comprising a cap configured to be mounted to the plug base over the retainer and firmly secure the medical device within the at least one exit groove.

111. The burr hole plug of article 107, wherein the at least one exit groove comprises a plurality of grooves circumferentially distributed in the retainer.

ES 2 394 045 T3

112. The burr hole plug of item 107, wherein the at least one exit groove is configured to seat the medical device when bent at a ninety degree angle relative to an axis of the burr hole.

113. The burr hole plug of item 107, wherein the retainer is configured to be removably mounted within the opening of the plug base.

114. The burr hole plug of item 107, wherein the plug base includes at least one annular inner boss configured to support the retainer when mounted within the opening of the plug base.

115. The burr hole plug of article 107, wherein the retainer further includes a retainer bracket and a slot formed in the retainer bracket to receive the medical device.

116. The burr hole plug of item 115, wherein the retainer includes a clamping mechanism configured to apply a clamping force to the medical device received within the slot.

117. The burr hole plug of item 116, wherein a clamping mechanism includes a clamping bar, configured to engage the medical device, and a locking element, configured to lock the clamping bar relative to the retainer bracket when the medical device is insured.

118. The burr hole plug of article 15, wherein at least one of the one or more exit grooves is oriented radially perpendicular to the groove.

119. The burr hole plug of item 115, wherein the retainer bracket is a disc.

120. The burr hole plug of item 107, further comprising fasteners configured to anchor the plug base to a skull of a patient.

121. A method of performing a medical procedure on a patient, comprising:

introducing an elongated medical device through a cranial trephine hole of the patient and into the brain tissue of the patient;

mounting a plug base around a cranial burr hole such that the medical device extends through an opening in the plug base.

mounting a retainer within the opening of the plug base;

actuate the retainer to secure the medical device;

radially directing the medical device toward the cap base by seating the medical device within an outlet groove of the retainer; and mounting a cap to the cap base over the retainer, wherein the medical device is secured between the cap base and the cap.

122. The method of article 121, wherein the medical device is an electrical cord.

123. The method of article 121, wherein the medical device is secured within the exit groove when the cap is mounted to the cap base over the retainer.

124. The method of article 121, further comprising bending the medical device at an angle relative to an axis of the burr hole prior to seating the medical device within the exit groove.

125. The method of article 124, where the angle is a ninety degree angle.

126. The method of article 121, further comprising selecting one of a plurality of retainer outlet grooves, wherein the medical device sits within the selected outlet groove.

127. The method of article 121, wherein the medical device is secured within a slot formed in the retainer, and the exit groove is oriented radially perpendicular to the slot.

128. A trephine hole plug, comprising:

a plug base configured to be mounted around a skull burr hole, the plug base includes an opening through which a plurality of elongated medical devices exiting the burr hole can pass; Y

ES 2 394 045 T3 a retainer configured to be mounted within the opening of the plug base, the retainer includes first and second sliding fastening mechanisms configured to secure the medical devices therebetween within the opening of the plug base .

129. The burr hole plug of article 128, wherein the opening of the plug base is circular.

130. The burr hole plug of article 128, wherein the largest dimension of the opening is equal to or less than 25mm.

131. The burr hole plug of article 128, wherein the retainer is configured to be removably mounted within the opening of the plug base.

132. The burr hole plug of article 128, wherein the plug base includes at least one annular inner boss configured to support the retainer when mounted within the opening of the plug base.

133. The burr hole plug of item 128, wherein the first and second slide clamping mechanisms are configured to secure the medical devices along one of a plurality of cords of the plug base opening.

134. The burr hole plug of article 128, wherein the retainer further includes a retainer bracket and a slot formed in the retainer bracket to receive medical devices, and wherein the first and second clamping mechanisms are slidably engaged with the retainer bracket to secure the received medical devices within the slot.

135. The burr hole plug of item 134, wherein the retainer bracket is a disc.

136. The burr hole plug of item 134, wherein each of the first and second clamping mechanisms has a clamp bar and a sliding flange slidably engaged with the retainer bracket to laterally slide the clamp bar to secure the devices doctors received inside the slot

137. The burr hole plug of item 136, wherein at least one of the first and second clamp bars has a clamping surface with relief characteristics.

138. The burr hole plug of item 136, wherein each of the first and second clamping mechanisms has a locking element configured to lock the respective clamping bar relative to the retainer bracket when the medical devices are secured.

139. The burr hole plug of item 134, wherein the retainer includes first and second recesses formed in the retainer bracket on opposite sides of the slot, where the sliding ridges of the first and second fasteners are slidably engaged within the respective recesses.

140. The plug burr hole of section 139, wherein the retainer includes first and second pairs of channels C, provided each pair on opposite sides of the respective recess, in which a pair of opposite sides of each sliding flange are received resp ectivamente within the channels in C.

141. The burr hole plug of item 134, wherein the slot is configured to laterally receive medical devices.

142. The burr hole plug of item 134, wherein the retainer bracket includes first and second portions, and the retainer further includes a hinge coupled to the first and second flange portions, whereby the first and second portions The flanges may alternately be hinged open to laterally receive the medical cables within the slot and be hinged closed to encircle the medical cable within the slot.

143. The burr hole plug of article 128, further comprising fasteners configured to anchor the plug base to a skull of a patient.

144. The burr hole plug of article 128, further comprising a cap configured to be mounted to the plug base over the retainer.

145. The burr hole plug of item 143, wherein the plug base has a plurality of outlet grooves configured to respectively seat the medical devices, and wherein the

ES 2 394 045 T3 cap is configured to securely secure medical devices within the outlet grooves when the cap is mounted on the cap base.

146. A method of performing a medical procedure on a patient, comprising:

introducing at least one elongated medical device through a cranial trephine hole of the patient and into the brain tissue of the patient;

mounting a plug base around the cranial burr hole such that the at least one medical device extends through an opening in the plug base;

mounting a retainer within the opening of the plug base, the retainer including first and second clamping mechanisms; and sliding the first and second clamping mechanisms to secure the at least one medical device in between.

147. The method of article 146, wherein each of the at least one medical device is an electrical cord.

148. The method of article 146, wherein the at least one medical device comprises a plurality of medical devices.

149. The method of item 148, wherein the first and second clamping mechanisms secure the medical devices along an off-center chord of the cap base opening.

150. The method of article 146, wherein the retainer further includes a retainer bracket and a slot formed in the retainer bracket to receive the medical devices, the method further comprises receiving the at least one medical device in the slot, and wherein the first and second clamping mechanisms are slidable with respect to the retainer bracket to secure the at least one received medical device within the slot.

151. The method of item 146, further comprising mounting a cap to the plug base over the retainer.

152. A trephine hole plug, comprising:

a plug base configured to be mounted around a cranial burr hole, the plug base includes an opening through which an elongated medical device exiting the burr hole can pass; and a retainer that includes a retainer bracket configured to be mounted within the cap base opening, and a fastener configured to mate with the retainer bracket to secure the medical device between the fastener and a retainer bracket clamping surface. .

153. The burr hole plug of item 152, wherein the opening of the plug base is circular.

154. The burr hole plug of item 152, wherein the largest dimension of the opening is equal to or less than 25mm.

155. The burr hole plug of item 152, wherein the retainer bracket is configured to be removably mounted within the opening of the plug base.

156. The burr hole plug of item 152, wherein the plug base includes at least one annular inner boss configured to support the retainer bracket when mounted within the opening of the plug base.

157. The burr hole plug of item 152, wherein the retainer bracket is semi-circular.

158. The burr hole plug of item 152, wherein the fastener is configured to mate with the retainer bracket in an interference arrangement.

159. The burr hole plug of item 152, wherein the retainer bracket includes a pair of C-channels, and the fastener includes a pair of resilient arms configured to slideably engage the opposing C-channels.

160. The burr hole plug of item 159, wherein the fastener includes a pair of tabs respectively disposed at the ends of the arms, wherein the tabs are configured to

ES 2 394 045 T3 engage respectively with the ends of the opposing C-channels to lock the fixator with respect to the retainer bracket

161. The burr hole plug of item 160, wherein the arms are configured to be displaced towards each other away from the rails to disengage the flanges from the opposing C-channels.

162. The burr hole plug of item 152, further comprising fasteners configured to anchor the plug base to a skull of a patient.

163. The burr hole plug of item 152, further comprising a cap configured to be mounted to the plug base over the retainer.

164. The burr hole plug of Item 163, wherein the plug base has an outlet groove configured to seat the medical device, and wherein the cap is configured to firmly secure the medical device within the outlet groove when the cap is mounted on plug base.

165. A method of performing a medical procedure on a patient, comprising:

introducing an elongated medical device through a cranial trephine hole of the patient and into the brain tissue of the patient;

mounting a plug base around a cranial burr hole such that the medical device extends through an opening in the plug base.

mounting a retainer bracket within the opening of the plug base; and mating a fixator with the retainer bracket to secure the medical device between the fixator and a clamping surface of the retainer bracket.

166. The method of article 165, wherein the medical device is an electrical cord.

167. The method of item 165, wherein the fixator is paired with the retainer bracket with an interference arrangement.

168. The method of item 165, wherein the retainer bracket includes a pair of opposing C-channels, the fixator includes a pair of spring arms, and the fixator is paired with the retainer bracket by sliding the arms into the channels. in C.

169. The method of item 168, wherein the fastener includes a pair of tabs respectively disposed at the ends of the arms, and the arms are slid into the opposing C-channels until the tabs respectively engage the ends of the channels at C opposites, thereby closing the fastener relative to the retainer holder.

170. The method of item 169, further comprising moving the arms toward each other away from the C-channels to disengage the flanges from the opposing C-channels.

171. The method of item 165, further comprising mounting a cap to the plug base over the retainer.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings illustrate the design and utility of preferred embodiments of the present invention, in which like elements are designated by common reference numerals. In order to better appreciate how the aforementioned and other advantages and objectives of the present inventions are obtained, a more particular description will be made of the present inventions briefly described above with reference to specific embodiments thereof, which are illustrated in the attached drawings. Understanding that these drawings only represent typical embodiments of the invention and that therefore they should not be considered as limiting its scope, the invention will be described and explained in additional specificity and detail with the use of the accompanying drawings in which:

Figure 1 is a plan view of a Deep Brain Stimulation (DBS) system constructed in accordance with one embodiment of the present inventions, wherein the DBS system is shown particularly implanted within a patient;

Figure 2 is an exploded perspective view of a first embodiment of a burr hole plug that may be used in the DBS system of Figure 1;

Figure 3 is a top perspective view of the burr hole plug of Figure 2;

Figure 4 is a bottom perspective view of the burr hole plug of Figure 2;

Figure 5 is a top view of the burr hole plug of Figure 2;

Figure 6 is a side view of the burr hole plug of Figure 2;

Figure 7 is a cross-sectional view of the burr hole plug of Figure 2;

Figure 8 is a top perspective view of a plug base used in the burr hole plug of Figure 2;

Figure 9 is a bottom perspective view of the plug base of Figure 8;

Figure 10 is a bottom perspective view of a second embodiment of a burr hole plug that may be used in the DBS system of Figure 1;

Figure 11 is a side view of the burr hole plug of Figure 10;

Figure 12 is a top perspective view of an alternative plug base that may be used in the burr hole plug of Figure 10;

Figure 13 is a bottom perspective view of the plug base of Figure 12;

Figure 14 is a close-up bottom perspective view of the plug base of Figure 8;

Figure 15 is a top close-up view of the burr hole plug of Figure 2;

Figure 16 is a top view of another alternative plug base that may be used in the burr hole plug of Figure 2;

Figure 17 is an integrated top perspective view of yet another alternative plug base that may be used in the burr hole plug of Figure 2;

Figure 18 is an exploded top perspective view of the plug base of Figure 17; Figures 18a and 18b are top perspective views of still other alternative plug bases that may be used in the burr hole plug of Figure 2;

Figure 19 is a top perspective view of yet another alternate embodiment of a plug base that may be used in the burr hole plug of Figure 2;

Figures 20 and 21 are cross-sectional views of the plug base of Figure 19, particularly showing one embodiment of a mechanism for mounting the plug base within a burr hole;

Figures 22 and 23 are cross-sectional views of the plug base of Figure 19, particularly showing another embodiment of a mechanism for mounting the plug base within a burr hole;

Figures 24 and 25 are cross-sectional views of the plug base of Figure 19, particularly showing yet another embodiment of a mechanism for mounting the plug base within a burr hole;

Figures 26 and 27 are cross-sectional views of the plug base of Figure 19, particularly showing yet another embodiment of a mechanism for mounting the plug base within a burr hole;

Figure 28 is a top perspective view of a retainer used in the burr hole plug of Figure 2;

Figure 29 is a bottom perspective view of the retainer of Figure 28;

Figure 30 is a top view of the retainer of Figure 28, particularly showing the clamping mechanism in an open position;

Figure 31 is a bottom view of the retainer of Figure 28, particularly showing the clamping mechanism in an open position;

Figure 32 is a top view of the retainer of Figure 28, particularly showing the clamping mechanism in a closed position;

Figure 33 is a bottom view of the retainer of Figure 28, particularly showing the clamping mechanism in a closed position;

Figure 34 is a bottom perspective view of a retainer bracket used in the retainer of Figure 28;

Figure 35 is a top perspective view of a clamping mechanism used in the retainer of Figure 28;

Figure 36 is a bottom perspective view of the clamping mechanism of Figure 35;

Figure 37 is a top perspective close-up view of the retainer of Figure 28, particularly showing the clamping mechanism in a closed position;

Figure 38 is a close-up perspective top view of the retainer of Figure 28, particularly showing the clamping mechanism in an open position;

Figures 39A-39E are plan views showing the technique in which the clamping mechanism and the retainer bracket of the retainer of Figure 28 interact to lock and unlock the clamping mechanism of the retainer bracket;

Figure 40 is a plan view showing an alternative technique in which the clamping mechanism and the retainer bracket of the retainer of Figure 28 interact to lock and unlock the clamping mechanism of the retainer bracket;

Figure 41 is a plan view showing another alternative technique in which the clamping mechanism and the retainer bracket of the retainer of Figure 28 interact to lock and unlock the clamping mechanism of the retainer bracket;

Figures 42A-42N are perspective views showing different relief surfaces that can be used for the clamping mechanism of Figure 35;

Figure 43 is a plan view of an interlock relief structure that can be used for the clamping mechanism of Figure 35;

Figure 44 is a top perspective view of an alternate embodiment of a retainer that may be used in the burr hole plug of Figure 2;

Figure 45 is a top perspective view of another alternate embodiment of a retainer that may be used in the burr hole plug of Figure 2;

Figures 45a-45f are top views of still other alternative embodiments of a retainer that may be used in the burr hole plug of Figure 2;

Figure 46 is a schematic illustrating different cords by which stimulation leads can be attached by the retainer of Figure 45;

Figure 47 is a schematic illustrating additional cords with which the stimulation leads can be attached by the retainer of Figure 45;

Figure 48 is a top perspective view of yet another alternative embodiment of a retainer that may be used in the burr hole plug of Figure 2, shown particularly in an unattached position;

Figure 49 is a top perspective view of the retainer of Figure 48, shown particularly in a clamped position;

Figure 50 is a top perspective view of yet another alternative embodiment of a retainer that may be used in the burr hole plug of Figure 2, shown particularly in an unattached position;

Figure 51 is a top perspective view of the retainer of Figure 50, shown particularly in a clamped position;

Figure 52 is a top perspective view of a cap used in the burr hole plug of Figure 2;

Figure 53 is a bottom perspective view of the cap of Figure 52;

Figure 54 is a top view of a plug base holding tool that can be used to mount the plug base of Figure 8 into a burr hole;

Figure 55 is a side view of the plug base holding tool of Figure 54, shown particularly in engagement with the plug base of Figure 8;

Figure 56 is a side view of the plug base holding tool of Figure 54, shown particularly uncoupled from the plug base of Figure 8;

Figure 57 is a top view of another plug base holding tool that can be used to mount the plug base of Figure 8 into a burr hole;

Figure 58 is a side view of the plug base holding tool of Figure 57, shown particularly in engagement with the plug base of Figure 8;

Figure 59 is a top perspective view of yet another plug base holding tool that can be used to mount the plug base of Figure 8 into a burr hole, particularly showing the tool disengaged from the plug base. ;

Figure 60 is a top perspective view of the cap base holding tool of Figure 59, particularly showing the tool engaged with the cap base;

Figure 61 is a cross-sectional view of the plug base holding tool and plug base of Figure 60;

Figure 62 is a top perspective view of a screw alignment mechanism of the plug base holding tool of Figure 59;

Figure 63 is a top perspective view of an insert used in the screw alignment mechanism of Figure 62;

Figure 64 is a top perspective view of a collar used in the screw alignment mechanism of Figure 62;

Figure 65 is a top, close-up perspective view of a screw alignment mechanism that can be used with the plug base holding tool of Figure 59;

Figure 66 is a close-up cross-sectional view of the screw alignment mechanism of Figure 65;

Figure 67 is a cross-sectional view of another alternative screw alignment mechanism that can be used with the plug base holding tool of Figure 59;

Figure 68 is a top perspective view of the screw alignment mechanism of Figure 67;

Figure 69 is a top perspective view of the screw alignment mechanism of Figure 67, particularly showing the mounted screw disposed within the collar;

Figure 70 is a top perspective view of one embodiment of a retainer holding tool engaged with a retainer;

Figure 71 is a side view of the retainer holding tool of Figure 70;

Figure 72 is a cross-sectional view of a leg of the retainer holding tool engaged with the retainer;

ES 2 394 045 T3

FIGURE 73 is a perspective view of another embodiment of a retainer holding tool;

Figure 74 is a perspective view of the retainer holding mechanism of the retainer holding tool of Figure 73;

Figure 75 is a close-up perspective view of the retainer holding tool of Figure 73, shown particularly in assembling the retainer of Figure 28 with the plug base of Figure 8;

Figure 76 is a perspective view of the retainer holding mechanism of Figure 74, particularly showing the retainer holding mechanism in imaginary line;

Figure 77 is a close-up view of the blunt tip of the retainer holding tool of Figure 73;

FIGURE 78 is a perspective view of yet another embodiment of a retainer holding tool;

Figure 79 is a close-up view of the retainer holding tool of Figure 78;

Figure 80 is a close-up view showing a portion of the retainer holding tool of Figure 78 in imaginary line;

Figure 81 is a side view of the plug base of Figure 8 mounted within a burr hole; Figure 82 is a side view of the plug base of Figure 12 mounted within a burr hole;

Figure 83 is a perspective view of the assembled plug base of Figure 81, particularly showing a stimulation lead disposed through the opening in the plug base;

Figure 84 is a perspective view of the plug base of Figure 16, prior to mounting within a burr hole, particularly showing a stimulation wire disposed through the plug base opening;

Figure 85 is a perspective view of a portion of the plug base of Figure 17 mounted within a burr hole;

Figure 86 is a perspective view of the remaining portion of the plug base of Figure 17 mounted within a burr hole;

Figure 87 is a perspective view of the retainer of Figure 28, mounted within the plug base shown in Figure 83, particularly showing the clamping mechanism in an open position;

Figure 88 is a perspective view of the clamping mechanism of Figure 48, prior to being mounted within the plug base shown in Figure 83, particularly showing the clamping mechanism in an unclamped position;

Figure 89 is a perspective view of the clamping mechanism of Figure 48, prior to mounting within the plug base shown in Figure 83, particularly showing the clamping mechanism in a clamped position;

Figure 90 is a perspective view of the retainer of Figure 28, mounted within the plug base shown in Figure 83, particularly showing the clamping mechanism in a closed position;

Figure 91 is a perspective view of the retainer retention disk of Figure 58 mounted within the plug base shown in Figure 83;

Figure 92 is a perspective view of the retainer fastener of Figure 58 mounted on the retention disc shown in Figure 91;

Figure 93 is a perspective view of the retainer of Figure 45 mounted within the plug base shown in Figure 83;

Figure 94 is a perspective view of the retainer of Figure 28, mounted within the plug base shown in Figure 83, particularly showing the clamping mechanism in a closed position; and Figure 95 is a perspective view of the cap of Figure 52 mounted on the cap base shown in Figure 83.

DETAILED DESCRIPTION OF THE REALIZATIONS

Turning first to Figure 1, there is shown an example of a DBS system 10 constructed in accordance with an embodiment of the present inventions implanted within a patient for the treatment of a debilitating disease such as Parkinson's disease, dystonia, essential tremor, disorders of epilepsy, obesity, depression, etc. The system 10 comprises a stimulation cable 12 implanted within the parenchyma of the brain 2 of a patient 1 in order to place electrodes 14 carried by the distal end of the stimulation cable 12 next to a region 3 of target tissue, such as a Deep structure of the patient's brain (eg, ventrolateral thalamus, inner segment of globus pallus, pars reticulate of substantia nigra, subthalamic nucleus, or outer segment of globus pallus). In this way, electrical stimulation energy can be transmitted from electrodes 14 to region 3 of the target tissue to treat disease. As can be seen, the stimulation lead 12 is introduced into the head 4 of patient 1 through a burr hole 5 formed in the skull 6 of patient 1. In alternative embodiments, multiple stimulation leads (not shown) can be used, all of which can be positioned within the head 4 of patient 1 through the same burr hole 5, as will be described in further detail below.

ES 2 394 045 T3

To secure the stimulation lead 12 (or leads) and to prevent infection and cerebral spinal fluid leakage, the system 10 further comprises a burr hole plug 16 mounted in the skull 6 around the patient's trephine hole 5. 1. Stim lead 12 extends from burr hole 5, through burr hole plug 16, to a location external to skull 6. Details explaining the structure and function of various embodiments of the burr hole plug 16 will be explained in further detail later.

The DBS system 10 further comprises a neurostimulator 17, such as an implantable pulse generator (IPG), radio frequency (RF) receptor-stimulator or any other device coupled and capable of delivering stimulus electrical energy to the stimulation lead 12 of a controlled and therapeutic way. The neurostimulator 17 can generally be implanted into a surgically made pocket in the patient's torso (eg, the chest or shoulder region). The neurostimulator 17 can, of course, also be implanted in other locations on the patient's body. The DBS system 10 further comprises a lead extension 19, which can be conveniently connected to the proximal end of the stimulation lead 12 and advanced subcutaneously under the scalp 7 of patient 1 to the neurostimulator implantation site, thereby facilitating placement of the neurostimulator 17 away from the exit point of the stimulation lead 12 (ie, the burr hole 5). In alternative embodiments, neurostimulator 17 can be implanted directly on or into skull 6 of patient 1, as described in US Patent No. 6,920,359. In this case, the cable extension 19 may not be necessary. After implantation, the neurostimulator 17 is used to provide the therapeutic stimulus under the control of the patient 1. System 10 may include external components, such as a handheld patient programmer, clinical programming station, and external charger (none shown), details thereof will not be described herein for brevity.

It should be understood that while the invention lends itself to applications in DBS, the invention, in its broader aspects, may not be so limited. For example, stimulation lead 12 (or leads) may be delivered within brain regions other than deep brain structure, eg, within or on the surface of the cerebral cortex. Furthermore, electrical leads other than the stimulation leads may be delivered within the head 4 of the patient 1. For example, an electrical recording lead may be delivered to the head 4 of patient 1 through the burr hole 5 to sense brain signals, either alone or in conjunction with a stimulation lead. Furthermore, elongated medical devices other than electrical cables; for example, catheters or drug delivery needles, can be inserted into the head 4 of the patient 1 through the burr hole 5. Thus, it can be appreciated that the burr hole plugs described herein can be used with any elongated medical device intended to be delivered through a burr hole 5 into the skull 6 of a patient 1 for therapeutic purposes and / or or diagnostic.

Referring now to Figures 2-7, one embodiment of a burr hole plug 16 will be described. The burr hole plug 16 generally comprises a plug base (or skeleton) 18 configured to be fixedly mounted around the a burr hole, a retainer 20 configured to be mounted within the plug base 18 and to temporarily secure a stimulation wire that runs through the burr hole, and a cap 22 configured to be mounted to plug base 18 over retainer 20 to permanently secure the stimulation lead while sealing the burr hole. The burr hole plug 16 further comprises a plurality of fasteners, and in this case, a pair of screws 14, for mounting the plug base 18 to the skull 6 of patient 1.

Referring further to Figures 8 and 9, the plug base 18 includes a closed ring-shaped body 24 and an opening 26 through which the stimulation wire exiting the burr hole can pass. The ring-shaped body 24 is comprised of a suitable, hard, biocompatible material, such as titanium, stainless steel, hard alloys, or polymers. The profile of the ring-shaped body 24 is preferably minimized as much as possible, such that the plug base 18 does not protrude noticeably from the skull under the patient's hair. As best shown in Figure 6, the upper surface 28 of the ring-shaped body 24 may also be tapered to further reduce the visibility of the burr hole plug 16 under the patient's hair. The lower surface 30 of the ring-shaped body 24 may optionally be concave (not shown) to match the curvature of a typical skull. The opening 26 in the plug base preferably matches the shape and size of the burr hole. For example, the opening 26 may have a circular shape and its largest dimension may be equal to or less than 25mm. Thus, it can be appreciated that the ring-shaped body 24 can be arranged around the burr hole such that the aperture 26 is coincident and is just above the burr hole.

To ensure that the ring-shaped body 24 is centered relative to the burr hole, the plug base 18 further comprises a plurality of self-centering tabs 32 configured to extend into the burr hole. In the illustrated embodiment, the tabs 32 are disposed on the lower surface 30 of the ring-shaped body 24, so that the tabs 32 do not obstruct the passage of the stimulation lead through the plug base opening 26. In particular, because the flanges 32, compared to a continuous cylindrical rim, are independently flexible, the plug base 18 can be centered within holes of

ES 2 394 045 T3 burr holes that are slightly smaller than the circumference defined by flanges 32. Thus, plug base 18 can be used with different sized burr holes.

Plug base 18 preferably includes at least three tabs 32 equally spaced around aperture 26 in order to maximize centering function. The flanges 32 are preferably arranged in such a way that they fit snugly against the inner surface of the circumference of the burr hole to prevent any movement of the plug base 18 relative to the burr hole. In this case, the tabs 32 will be coincident with the plug base opening 26 (assuming that the opening 26 is the same size and shape as the burr hole). Flanges 32 are designed to be permanently disposed on ring-shaped body 24 such that flanges 32 will remain located within the burr hole after implantation. Flanges 32 may be conveniently arranged on ring-shaped body 24, for example, by molding flanges 32 and body 24 as a single body design. Significantly, the self-centering tabs 32 quickly and conveniently allow the plug base 18 to be centered with respect to the burr hole without the aid of a special centering tool.

In the illustrated embodiment, the plug base 18 is permanently anchored to the skull of the patient. To this end, the plug base 18 includes two clamping holes 34 formed within the ring-shaped body 24 to respectively receive anchor clips, such as screws, pins, tips, tabs or buttons. Alternatively, other means may be used to anchor the plug base 18 to the patient's skull, such as, for example, adhesion. Relief structures (not shown) may be added to the lower surface 30 of the ring-shaped body 24 and the outer surfaces of the flanges 32 to prevent rotational movement between the plug base 18 and the burr hole prior to permanent anchoring. to the skull. Such relief structures may include, for example, a rough surface such as sandpaper, notches, bumps, horizontal or vertical ribs or threads, etc.

The plug base 18 further comprises a plurality of lead exit grooves 36 (in this case, four equidistant grooves) configured to seat the stimulation lead. In particular, the portion of the stimulation lead that exits the burr hole through the opening 26 of the plug base 18 (i.e., the proximal end of the stimulation lead) can be bent down at a perpendicular angle and seated within one of the cable exit grooves 36 of the plug base 18, such that the proximal end of the stimulation cable is generally parallel to the outer surface of the skull. As will be described in further detail below, the stimulation lead will be securely secured within the selected exit groove 36 when the cap 22 is mounted on the cap base 18.

Cap base 18 further comprises an off-cap pop-up recess 38 located on an inner edge 40 of ring-shaped body 24 adjacent opening 26, and a plurality of cap-locking recesses 42 (in this case, a pair of oppositely arranged recesses). As will be described in further detail below, a tool may be inserted into the off-cap snap recess 38 to remove the previously assembled cap 22 from the cap base 18, and the cap locking recesses 42 may receive corresponding tabs of the cap. cap lock (described below) to facilitate mounting of cap 22 on cap base 18.

Plug base 18 also comprises at least one annular inner boss 44 (in this case, three equidistant annular bosses) configured to support retainer 20 when mounted within plug base opening 26. To this end, annular projections 44 are disposed on an inner surface 46 (best shown in Figure 14) of ring-shaped body 24 surrounding aperture 26, thereby preventing retainer 20 from descending too far into the bore hole. trephine when mounted within aperture 26. In an alternative embodiment illustrated in Figures 10-13, a plug base 57 is similar to plug base 18, with the exception that it comprises at least one annular flange 45 (in this case, one) extending from the respective annular projections 44 below the lower surface 30 of the ring-shaped body 24. Thus, it can be appreciated that the annular flange 45 allows the upper surface of the annular projections 44 to be flush with the lower surface 30 of the plug base body 24, so that the retainer 20 can be recessed further downward. in the burr hole (compare the location of the retainer in Figure 11 with Figure 6).

Referring again to Figures 8 and 9, and further to Figures 14 and 15, the plug base 18 further comprises a plurality of mechanisms that lock the retainer 20 in place by preventing, or at least hindering, rotation. of the retainer 20 within the plug base opening 26. In particular, plug base 18 includes a plurality of ramps 48 (only one is shown in Figure 15) disposed around inner surface 46 of ring-shaped body 24 just above annular projections 44. Ramps 48 taper inwardly from top to bottom, such that when retainer 20 is forced down into opening 26, the edges of retainer 20 slidably engage ramps 48 and then engage. move past ramps 48 until retainer 20 seats between annular projections 44 and bearing surfaces 50 (the bottom surfaces) (best shown in Figure 14) of ramps 48, thereby providing

ES 2 394 045 T3 is an interference fit that locks retainer 20 within plug base opening 26. Preferably, the vertical distance between the abutment surfaces 50 of the ramps 48 and the annular projections 44 is approximately equal to the thickness of the retainer 20, such that the retainer 20 cannot move up or down within the opening 26 a time locked on site. Once the retainer 20 is positioned between the bearing surfaces 50 of the ramps 48 and the annular projections 44, the ramps 48 also engage corresponding sundial markings (described below) located on the upper surface of the retainer 20. when retainer 20 is rotated within aperture 26, thereby limiting rotation of retainer 20, and thus any involuntary movement of the stimulation lead, as will be described in further detail later.

In the embodiment illustrated in Figures 8 and 9, the ring-shaped body 24 is closed, which maximizes the durability of the plug base 18. Alternatively, a slotted plug base 58 may include an open ring-shaped body 64, as illustrated in Figure 16. In particular, the open ring-shaped body 64 is similar to the closed ring-shaped body 24, except that it comprises an open slot 66 configured to laterally receive the stimulation lead. This allows the plug base 58 to be mounted in the skull around the burr hole after the stimulation wire has been inserted through the burr hole and into brain tissue simply by sliding the stimulation wire through the slot. 66 when the plug base 58 is moved into place. In particular, because the open architecture of the ring-shaped body 64 inherently weakens its structure, the ring-shaped body 64 is preferably composed of a highly durable material, such as titanium, thereby overcoming any issue. intrinsically within the open ring shaped body, such as excessive bending. In a particularly advantageous embodiment, the ring-shaped body 64 is composed of polyetheretherketone (PEEK), which is not only very durable and biocompatible, but is also MRI-compatible, and most importantly, it will not distort the MRI. Alternatively, the ring-shaped body 64 can be comprised of nylon, silicone, Utlem®, Elasthan®, Tecothane®, and / or Bionate®.

In an alternative embodiment, a split plug base 78 illustrated in Figures 17 and 18 may be used. Plug base 78 is similar to plug base 18 illustrated in Figures 8 and 9, except that plug base 78 comprises a plurality of annular body parts, and in particular a first annular body part 80. and a second annular body portion 82, which are configured to be unpaired from each other to separate the plug base 78 (Figure 18) and to be paired with each other to integrate the plug base 78 (Figure 17). Plug base 78 also differs from plug base 18 in that it comprises a continuous annular rim 79 (rather than self-centering flanges 32) that fits within the cranial burr hole. Cap base 78 is also shown without a cap-off jump recess 38, cap lock recesses 42, or ramps 48.

In the illustrated embodiment, opposite ends 84, 86 of the first annular body part 80 respectively include a female coupling element 92 and a male coupling element 94, and opposite ends 88, 90 of the second annular body part 82 they respectively include a male coupling element 96 and a female coupling element 98. The male and female elements 92-98 coincide with each other, such that the ends 84, 88 of the annular body parts 80, 82 can be mated together by receiving the male coupling element 96 of the second annular body part 82 at the female coupling element 92 of the first annular body part 80, and the ends 86, 90 of the annular parts 80, 82 The body parts can be wedged together by receiving the male coupling element 94 of the first annular body part 80 in the female coupling element 98 of the second annular body part 82. Alternatively, both male coupling elements 94, 96 can be positioned at opposite ends 84, 86 of the first annular body part 80, and both female coupling elements 92, 98 can be positioned at opposite ends 88, 90 of the second annular body part 82, or vice versa, with similar results.

In the embodiment illustrated in Figures 17 and 18, the male and female coupling members 92-98 are configured in such a way that the annular body portions 80, 82 can be mated together by lowering the second annular body portion 82 downward on top. of the first annular body part 80. In particular, the female and male coupling elements 92, 94 of the first annular body part 80 respectively take the form of a rectangular recess and a rectangular projection located on the upper surface of the first annular body part 80, and the elements male and female coupling 96, 98 of the second annular body part 82 respectively take the form of a rectangular protrusion and a C-channel extending laterally from the upper region of the second annular body part 82. Thus, when the second annular body part 82 is lowered onto the first annular body part 80, the laterally extending protrusion 96 of the second annular body part 82 will be received by the recess 92 of the first annular part 80. body, and the protrusion of the first annular body part 94 will be received by the C-channel 98 of the second annular body part 82.

Thus, it can be appreciated that annular body portions 80, 82 can be unpaired from one another to accommodate a stimulation lead that has already been inserted through a burr hole, and then paired together to integrate plug base 18 , which can then be anchored to the patient's skull. It should also be appreciated that since the plug base 18 is comprised of several independent components

ES 2 394 045 T3 that can move relative to each other, there is less chance of fracturing the plug base 78 when it is anchored to the skull of the patient.

Although the plug base 78 is designed to be separated into two pieces, it may still be desirable to alternatively maintain the plug base 78 as a single piece (i.e., as a prior art plug base), for example, when plug base 18 is to be mounted on the patient's skull prior to introducing the stimulation lead through the burr hole. To this end, the plug base 78 comprises additional coupling elements that firmly couple the annular body portions 80, 82 together. In the illustrated embodiment, these coupling elements take the form of complementary pins 100 and recesses (not shown) that are firmly coupled to each other, such that the annular, first and second body parts 80, 82 act as a pattern. single-bodied until they are intentionally separated. Once the annular body parts 80, 82 are unpaired from each other, the pins 100 can be broken or otherwise removed, so that the second annular body part 82 can be lowered down onto the first annular body part 80 of body when paired together unhindered by pins 100. Alternatively, the coupling elements may simply take the form of bonding material or other connection that can be easily fractured to unpair the annular body portions 80, 82 from one another.

In alternative embodiments, the complementary body parts 80, 82 can be attached together using a tool. For example, referring to Figure 18a, the complementary body parts 80, 82 can be integrated together using a rod 104, which allows the body parts 80, 82 to slide together linearly (shown by the double headed arrow). Both body parts 80, 82 may be temporarily attached to rod 104, so that rod 104 can be removed from body parts 80, 82 after they are paired together. Referring to Figure 18b, the complementary body parts 80, 82 can be integrated together using a threaded member 106, such as a screw, which is rotated to gradually force the body parts 80, 82 to slide linearly together.

Referring to Figures 19-21, another alternative embodiment of a plug base 108 will now be described. Instead of being permanently anchored to the skull of the patient, the plug base 108 can be reversibly anchored in a burr hole (i.e., it can be anchored without leaving any holes other than the burr hole in the skull), and still provide the benefits of a permanently anchored plug base 18. In particular, the plug base 108 generally comprises an upper body 110 in the shape of a plug ring, a lower body 112 in the shape of a plug ring, and a seal 114 in the shape of a ring (and in this case, an O-ring). disposed between plug bodies 110, 112. Seal 114 may be composed of a flexible, biocompatible material, such as silicone. The cap ring-shaped upper body 110 has a lower surface 116 with an outer annular recess 120 in which the seal 114 is disposed, and the cap ring-shaped lower body 112 has an upper surface 118 with an outer shoulder. ring 122 in which the seal 114 is arranged. Plug base 108 may have features (not shown) in plug ring shaped upper body 110; for example, an annular protrusion to support retainer 20, locking mechanisms to prevent rotation of retainer 20, or lead exit grooves to seat the stimulation lead.

The outer diameters of the plug bodies 110, 112 are substantially equal to the diameter of the burr hole, such that the plug base 108 can be disposed entirely within the burr hole. The outer diameter of seal 114, when decompressed (Figure 20), is substantially equal to the diameter of the burr hole. When seal 114 is compressed (Figure 21) in a vertical direction, which can be achieved by moving plug bodies 110, 112 toward each other, the outer diameter of seal 114 increases, thereby firmly engaging the surface of the bore. burr so that the burr hole is sealed. To this end, plug base 108 comprises fasteners, and in particular screws 124, which are disposed within threaded holes 126 formed through plug bodies 110, 112.

Thus, it can be appreciated that rotating the screws 124 in one direction using a tool, such as a screwdriver, will cause the cap bodies 110, 112 to be displaced toward each other, which will cause the annular shoulder 122 of the lower plug body 112 moves into annular recess 120 of upper plug body 110 to compress seal 114 in the vertical direction, thereby expanding the seal 114 in the horizontal direction to seal the plug base 108 within the burr hole. Rotation of the screws 124 in the opposite direction will cause the cap bodies 110, 112 to be displaced away from each other, which will cause the annular projection 122 of the lower cap body 112 to move out of the annular recess 120 of the cap. plug upper body 110 to allow seal 114 to expand in the vertical direction, thereby allowing seal 114 to compress in the horizontal direction to release plug base 18 from within the burr hole. Although only two screws 124 are shown, more than two screws (eg, four) may be used to ensure substantially uniform compression of seal 114 around its circumference.

ES 2 394 045 T3

In an alternative embodiment, a plug base 128 illustrated in Figures 22 and 23 is similar to the front plug base 108, except that it comprises upper and lower bodies 130, 132 shaped like a ring. plug that do not have annular recesses or projections. Instead, the cap bodies 130, 132 have respectively upper, lower and flat surfaces 134, 136, between which the seal 114 is disposed. Screws 138 are disposed within threaded holes 140 formed through plug bodies 130, 132, as well as through seal 114. Thus, it can be appreciated that rotating the screws 138 in one direction using a tool, such as a screwdriver, will cause the plug bodies 130, 132 to be displaced towards each other, which will cause the upper and lower surfaces to be displaced. 134, 136 compress the seal 114 in the vertical direction, thereby expanding the seal 114 in the horizontal direction to seal the plug base 128 within the burr hole. Rotation of screws 138 in the opposite direction will cause plug bodies 130, 132 to be displaced away from each other, to allow seal 114 to expand in the vertical direction, thus allowing seal 114 to compress into the horizontal direction to disassemble the plug base 128 from within the burr hole.

While the fasteners that displace the upper and lower plug bodies to compress the seal have been described as screws, other types of fasteners can be used, such as complementary mating elements that fit together in an interference arrangement. For example, as illustrated in Figures 24 and 25, flared pins 142 may be disposed on the lower surface 134 of upper plug body 130, and matching flared recesses 144 may be arranged on upper surface 136 of lower plug body 132. . Thus, the flared pins 142 can be respectively inserted through the holes 146 in the seal 114 and snap fit within the flared recesses 144, thereby causing the lower and upper surfaces 134, 136 to compress the seal 114. (FIG. 25) in the vertical direction, thereby expanding the seal 114 in the horizontal direction to seal the plug base 128 within the burr hole. A tool (not shown) can be used to hold the lower plug body 132 in place while the flared pins 142 snap into the flared recesses 144. The upper plug body 130 may be displaced from the lower plug body 132 to remove the flared pins 142 from the flared recesses 144 to allow the seal 114 to expand (Figure 24) in the vertical direction, thereby allowing the seal 114 is compressed in the horizontal direction to release plug base 128 from the burr hole.

In another alternate embodiment illustrated in Figures 26 and 27, another plug base 148 which can be non-invasively mounted within a burr hole will be described. Plug base 148 is similar to plug base 108 except that it includes a threaded collar 150 mounted to an upper surface 160 of lower plug body 132 by spacers 152 that extend through holes 154 in seal 114. In this case, the upper cap body 130 includes a threaded outer surface 156 that engages the threaded collar 150 to displace the upper cap body 130 relative to the lower cap body 132. Thus, it can be appreciated that rotating the upper cap body 130 in one direction will cause the cap bodies 130, 132 to be displaced toward each other, which will cause the lower and upper surfaces 134, 136 to compress the seal 114. (Figure 27) in the vertical direction, thereby expanding the seal 114 in the horizontal direction to seal the plug base 148 within the burr hole. Rotation of the upper plug body 130 in the opposite direction will cause the plug bodies 130, 132 to be displaced away from each other to allow the seal 114 to expand (Figure 26) in the vertical direction, thereby allowing the seal to expand. seal 114 is compressed in the horizontal direction to release plug base 148 from within the burr hole.

Referring to Figures 28-37, details of the retainer 20 will now be described. Retainer 20 generally comprises a retainer bracket 160 configured to be mounted within the plug base opening 26, and a clamping mechanism 162 mounted on retainer bracket 160 and configured to apply a clamping force to the stimulation lead. The clamping force applied to the stimulation cable secures the stimulation cable before and while the cap 22 is being mounted on the plug base 18 to more firmly secure the stimulation cable. The components of the retainer 20 may be composed of the same material as the plug base 18 described above; namely, a suitable, hard, biocompatible material, such as titanium, stainless steel, alloys, or hard polymers. Alternatively, the components of the retainer 20 may be composed of PEEK to provide certain structural advantages, as will be described in further detail below.

In the illustrated embodiment, retainer bracket 160 comprises a disc 164 and an open cable slot 166 formed in disc 164 to laterally receive the stimulation cable, thereby allowing retainer 20 to be mounted within opening 26 of the plug base after the stimulation lead has been inserted through the burr hole. As best shown in Figures 7 and 15, the retainer 20, and in particular the disc 164, can interfere with the ramps 48 and the annular projections 44 located on the inner surface 46 of the ring-shaped body 24. In the illustrated embodiment, the disk 164 has an annular lip 168 disposed around its circumference that interferes between the ramps 48 and the annular projections 44 of the ring-shaped body 24, and a thicker central portion 170 that extends underneath. of annular projections 44 to accommodate clamping mechanism 162 in a robust manner.

ES 2 394 045 T3

The annular projections 44 are displaced from the upper surface of the plug base 18 by a dimension that causes at least a part of the retainer 20, and in particular the disc 164, to be below the lower surface 30 of the body 24, with ring shape, plug. As a result, at least a portion of the disc 164 will be recessed within the burr hole when mounted within the plug base 18, thereby lowering the profile of the portion of the burr plug 16 above the burr hole. In the case where annular ridges 45 are provided, as illustrated in Figures 10-13, the disc 164 will be further recessed within the burr hole. Retainer 20 is configured to be removably mounted within plug base opening 26. To this end, the retainer bracket 160 further comprises an off-retainer jump notch 172 located on the circumference of the disc 164. The pop-out notch 172 may receive a tool that can be manipulated to pop the retainer 20 out of the plug base 18 (i.e., bypassing the interference fit between the ramps 48 and the annular projections 44 of the base 18 of plug). Alternatively, there may simply be a hole, hook, or eyelet in the disc to receive a tool to pop the retainer 20 out of the plug base 18.

As explained above, retainer 20, and in particular retainer bracket 160, comprises a plurality of sundial markings 174 that engage ramps 48, thereby limiting rotation of retainer 20 within aperture 26 plug base. In this case, the sundial markings 174 take the form of radially extending ribs that are distributed around the circumference on the upper surface 171 of the disk 164. In particular, as the circumferential distance between the sundial marks 174 decreases, the rotational movement of the retainer 20 within the opening 26 of the cap body 24 will decrease in increments by the same amount. In this illustrated embodiment, the circumferential spacing between the sundial markings 174 is approximately 24 degrees, and therefore the rotation of the retainer 20 will be limited to 24 degrees.

Retainer bracket 160 comprises a fixed holding bar 176 disposed on an inner edge of disk 164 adjacent to one side of cable slot 166. Clamping mechanism 162 works in conjunction with clamping fixed bar 176 to secure the stimulation lead therebetween, as will be described in further detail below. As best shown in Figure 34, the retainer bracket 160 further comprises a recess 178 formed in the disk 164 and a pair of C-channels 180 on opposite sides of the recess 178 to accommodate the clamping mechanism 162, and an obstacle recess 182 within recess 178 to accommodate a locking member of the clamping mechanism 162, as will be described later. Disc 164 may optionally have an "active hinge" that allows it to be bent along cable slot 166, thereby facilitating insertion of clamping mechanism 162 into disc 164 during assembly.

Clamping mechanism 162 comprises a movable clamp bar 184 and a flange 186 slidably engaged with disk 164 to laterally slide movable clamp bar 184 relative to disk 164 and selectively secure the received stimulation lead within the slot. 166 cable or release the received stimulation cable into the cable slot 166. Movable clamp bar 184 extends parallel to cable slot 166 opposite fixed clamp bar 176 in disk 164 such that a clamp surface 188 of movable clamp bar 184 is configured to clamp the cable. stimulation against a gripping surface 190 of gripping bar 176. In the illustrated embodiment, the clamping surfaces 188, 190 of the respective clamp bar 184 and clamp bar 176 have ribs in order to provide a localized grip of the stimulation lead, thereby increasing the retention force of the lead. . Clamping mechanism 162 further comprises an angled flange 192 located at the end of movable clamp bar 184, thereby preventing the stimulation cable from being positioned past movable clamp bar 184 at slot end 166 where it could potentially it could be wedged between the clamping mechanism 162 and the end of the slot 166.

In the illustrated embodiment, flange 186 is U-shaped and includes a pair of legs 194 that extend perpendicularly from movable clamp bar 184 away from cable slot 166 and a cross bar 196 that extends between legs 194 in a direction generally parallel to the cable slot 166. The U-shaped rim 186 further comprises rails 198 that extend along the outer surface of the legs 194. The sliding arrangement between the flange 186 of the clamping mechanism 162 and the disk 164 of the retainer bracket 160 is provided between the legs 194 of the U-shaped flange 186 and the C-channels 180 of the retainer bracket 160. In particular, U-shaped rim 186 is received within recess 178, with rails 198 of rim 186 slidably received within C-channels 180 in close tolerance relationship, such that rim 186, and thus the movable clamp bar 184 can be moved back and forth smoothly in a lateral direction (ie, perpendicular to the cable slot 166).

Clamping mechanism 162 is configured to be positioned between an unlocked (or open) position (Figures 30-31 and 38) where clamping mechanism 162 can be freely slid relative to disk 164, and a locked (or closed) position. ) (Figures 32-33 and 37) wherein the clamping mechanism 162 cannot be freely slid relative to the retainer bracket 160 without additional manipulation of the clamping mechanism 162. To this end, the clamping mechanism 162 further comprises a resilient arm 200 that extends perpendicularly from the movable clamping bar 184 between the legs 194 of the U-shaped flange.

ES 2 394 045 T3

186, and a locking element, and, in particular, a flange 202 located at the end of the resilient arm 200. The locking flange 202 is configured to engage a complementary locking element, and, in particular, the recessed obstacle 182 on disk 164 to lock movable clamp bar 184 relative to disk 164 when the stimulation cable is secured. In particular, as best illustrated in Figures 34-38, the locking flange 202 includes a bearing surface 204 configured to slide over a bearing surface 206 of the recessed obstacle 182 when the clamping mechanism 162 is in the unlocked position, and on a stop surface 208 abutting a stop surface 210 of the lowered obstacle 182 when the clamping mechanism 162 is in the locked position. The resilience of the arm 200, on which the locking flange 202 is disposed, will naturally cause the locking flange 202 to translate from the bearing surface 204 of the lowered obstacle 182 to the abutment surface 208 of the lowered obstacle 182 when the flange lock 202 reaches the end of the lowered obstacle 182.

In this way, the clamping mechanism 162 can be moved from the unlocked position (or open position) (Figure 39A) to the locked position (Figure 39C) by sliding the U-shaped flange 186, and thus the movable locking bar. clamping 184, relative to disk 164 towards fixed clamping bar 176 when bearing surface 204 of locking flange 202 slides along bearing surface 206 of lowered obstacle 182 until locking flange 202 reaches the end of lowered obstacle 182 (Figure 39B), after which the resilience of arm 200 will cause abutment surface 208 of locking flange 202 to abut abutment surface 210 of lowered obstacle 182 (Figure 39C).

The clamping mechanism 162 can be moved from the locked position (Figure 39C) to the unlocked position by applying a downward force on the resilient arm 200 to disengage the abutment surface 208, 210 from the respective locking flange 202 and the recessed obstacle 182 (Figure 39D), and slide the U-shaped flange 186, and thus the movable clamping bar 184, relative to disk 164 away from fixed clamping bar 176 until bearing surface 204 of locking flange 202 slides over bearing surface 206 of recessed obstacle 182 (Figure 39E).

Significantly, the relative dimensions between resilient arm 200, locking flange 202, and recessing obstacle 182 are selected such that abutment surface 208 of locking flange 202 becomes coincident with abutment surface 210. of the recessed obstacle 182 when the stimulation cable becomes secured between the clamping surface 188 of the movable clamping bar 184 and the clamping surface 190 of the fixed clamping bar 176. In this way, the firm grip of the stimulation cable is ensured without damaging the stimulation cable.

To facilitate manipulation of the clamping mechanism 162 with respect to the disk 164, the clamping mechanism 162 comprises a recess 212 formed in the bearing surface 204 of the locking flange 202 to receive a tool that can be used to flex the arm with resilience 200 in order to transition the clamping mechanism 162 from the locked position to the unlocked position. The tool may also be received within recess 212 to slide movable clamp bar 184 toward or away from fixed clamp bar 176 to secure or release the stimulation lead. It should be noted that recess 212 is closer to the center of disk 164 than the circumference of disk 164. Thus, when a downward force is applied to recess 212, any force applied to the circumference of disk 164, which may otherwise loosen or weaken the coupling between the sundial markings 174 on the surface, will be minimized or decreased. top 171 of disc 164 from ramps 48 onto inner surface 46 of ring-shaped plug body 24.

To further facilitate positioning of the clamping mechanism 162 from the locked position to the unlocked position, the bearing surface 204 of the locking flange 202, and thus the recess 212, may be angled (as best shown in Figure 35) with respect to the plane of disk 164, such that a portion of the downward force applied to recess 212 by the tool is transferred in a direction away from slot 166 along the plane of disk 164. In this way, when the flexible arm 200 is flexed, the abutment surface 204 of the locking flange 202 will naturally slide along the abutment surface 206 of the recessed obstacle 182 once the abutment surfaces 208, 210 of the respective locking flange 202 and the lowered obstacle 182 disengage from each other. In the embodiment illustrated in Figures 39A-39E, the abutment surfaces 208, 210 of the locking flange 202 and the recessed obstacle 182 are perpendicular to the plane of the disk 164, thereby maximizing the locking engagement of the clamping mechanism. 162. However, in an alternative embodiment illustrated in Figure 40, the abutment surfaces 208, 210 of the locking flange 202 and the recessed obstacle 182 are tapered (i.e., obliquely angled) relative to the plane of the disc 164, facilitating thereby positioning the clamping mechanism 162 from the locked position to the unlocked position.

To prevent the resilient arm 200 from being fatigued or broken, the clamping mechanism 162 further comprises an obstacle 214 that attaches to the U-shaped flange 186 to prevent the resilient arm 200 from bending past a certain point, such as is best shown in Figures 35 and 36. In the illustrated embodiment, the obstacle 214 is located in the center of the U-shaped flange 186 between the legs 194, so that the

ES 2 394 045 T3 inner surface 216 of resilient arm 200 abuts against an upper surface 218 of obstacle 214 when downward force is applied to locking flange 202.

In an alternative embodiment, the retainer bracket 160 has a plurality of complementary locking mechanisms with which the locking member of the clamping mechanism 162 is configured to selectively engage, such that the movable clamping bar 184 is configured to be positioned with respect to disk 164 in different positions. For example, as illustrated in Figure 41, the retainer bracket 160 may be provided with a ratchet 220 having teeth 222, to either of which the locking flange 202 of the resilient arm 200 can be engaged. Thus, the U-shaped lip 186 can slide into the cable slot 166 such that the abutment surface 208 of the locking flange 202 slides along the pawl 214. When movement of the U-shaped rim 186 ceases, the end of the resilient arm 200 will engage one of the teeth 222 on the ratchet 220. In this manner, different sized cables can be used with the burr hole plug 16. .

In particular, the retainer bracket 160 and the clamping mechanism 162 may have additional features that maximize the clamping force applied to the stimulation lead. For example, retainer 20, including retainer support 160 and clamping mechanism 162, can be comprised of PEEK, thereby substantially increasing the durability of retainer 20, even in view of the open architecture of retainer bracket 160. Since the deformation of the movable clamp bar 184 will be substantially decreased by the PEEK composition, the clamping force will be more evenly distributed along the movable clamp bar 184, thereby securing the stimulation wire in a more uniform manner. more reliable. The reduced deformation of U-shaped rim 186 and disk 164 will also allow clamping mechanism 162 to slide relative to retainer bracket 160 in a more reliable and robust manner.

In addition, the clamping surfaces 188, 190 of the movable clamp bar 184 and / or the fixed clamp bar 176 may be provided with any of a variety of relief features. For example, relief features may include horizontal ridges or bars (Figure 42A), dimples or bumps (Figure 42B), horizontal serrations (Figure 42C), vertical ripples (Figure 42D), stepped veneers (Figure 42E), curly pattern ( Figure 42F), spring (Figure 42G), spikes (Figure 42H), sand finish (shot blasted mold finish, plating) (Figure 421), non-slip surface (Figure 42J), spikes or spikes (Figure 42K), horizontal channel (Figure 42L), bent tines (Figure 42M), any combination of the above, for example horizontal ridges and concavities or bulges (Figure 42N).

The aforementioned relief characteristics will increase the holding force of the movable clamp bar 184 and / or the fixed clamp bar 176 by altering the coefficient of friction, increasing compression, "biting" in the cable, creating edges to catch the cable. cable, increasing the surface area, locally increasing the clamping force, deformation of the cable in surface recesses, etc. Combinations of multi-directional relief features on movable clamp bar 184 and / or fixed clamp bar 176 can prevent the cable from moving in multiple directions (for example, along the cable axis and along the cable axis). the face of movable clamping bar 184 and / or fixed clamping bar 176 perpendicular to the axis of the cable). Relief structures may be provided on clamping surfaces 188, 190 of movable clamp bar 184 and fixed clamp bar 176 to function in combination with each other to narrow or otherwise provide a sinuous path for the cable. For example, the relief structures on the clamping surfaces 188, 190 can be staggered or mutually interlocked (Figure 43) to constrict or create a sinuous path for the stimulation lead.

While the burr hole plug 16 illustrated in Figures 2-7 provides wire exit grooves 36 in the plug base 18, the wire exit grooves can be advantageously provided on the retainer instead. For example, referring to Figure 44, another retainer 230 that can be mounted within the opening 26 of the plug base 18 will now be described. Retainer 230 is similar to retainer 20 illustrated in Figures 28-33, except that it comprises a plurality of lead exit grooves 232 (in this case, two) configured to seat the stimulation lead when bent with a Angle of ninety degrees relative to the axis of the burr hole, such that the stimulation wire is directed radially toward the plug base 18. In this case, the plug base 18 need not include cable exit grooves. In the illustrated embodiment, exit grooves 232 are located on opposite sides of each other and are oriented circumferentially perpendicular to cable slot 166 and thus movable clamp bar 184. That is, an imaginary line drawn from each exit groove 232 at the center of disk 164 will be perpendicular to movable clamp bar 184. In this way, it is ensured that when the stimulation cable is bent down and received in one of the exit grooves 232, any tension force applied to the stimulation cable will be directed at an angle perpendicular to the orientation of the slot 166. cable length and thus will be counteracted by the retention force between the upper edges of the movable clamp bar 184 and the fixed clamp bar 176 and the stimulation cable.

Since there are two exit grooves 232, the direction in which the stimulation lead exits retainer 230 can be selected. In an alternative embodiment, a plurality of clamping exit grooves may be provided.

ES 2 394 045 T3 (not shown) on each side of the clamping slot 166, such that the stimulation lead can be positioned and bent perpendicularly downward at multiple locations along the clamping slot 166 . In another alternative embodiment, each clamping outlet groove 232 can slide back and forth in a direction parallel to the clamping slot 166, such that the stimulation lead can be positioned and bent perpendicularly downward at multiple locations. along the clamping groove 166.

While the above retainers 20, 230 include individual slide fastening mechanisms, retainers constructed in accordance with the present inventions may include more than one sliding attachment mechanism. For example, referring to Figure 45, another retainer 240 will now be described that can be mounted within the opening 26 of the plug base 18. As with the anterior retainer 20, the retainer 240 comprises a retainer bracket 242 that includes a disk 244 and an open slot 246 formed in the disk 244 to laterally receive the stimulation wire, thereby allowing the retainer 240 to be mounted within. of the plug base opening 26 after the stimulation lead has been inserted through the burr hole. Retainer 240 may include other features, such as a pop-out notch, such as sundial markings, and cable exit grooves (not shown) located in disk 244.

Retainer 240 differs from retainer 20 in that it comprises two sliding clamping mechanisms 252, each including a movable clamping bar 254 and a flange 256 slidably engaged with disc 244 to laterally slide movable clamping bar 254 relative to the disc 244 and selectively secure the received stimulation lead within the lead slot 246 or release the received stimulation lead within the lead slot 246. Movable clamping bars 254 extend parallel to opposing lead slot 246 such that clamping surfaces 258 (only one is shown) of respective clamping bars 254 are configured to hold the stimulation lead one against another. Like the clamping surfaces 188, 190 of the respective clamping bar 184 and the clamping bar 176 discussed above with respect to the retainer 20, the clamping surfaces 258 of the clamping bars 254 may have ribs or comprise other relief features ( not shown), thereby increasing the cable retention force. In addition, each clamping mechanism 252 may alternatively include a U-shaped ledge, resilient arm, locking tab, and an arm obstacle (not all shown) similar to the U-shaped ledge 186, resilient arm 200, locking flange 202 and arm obstacle 220 described above with respect to retainer 20.

Retainer 240 may include features formed in disk 244 to accommodate sliding clamping mechanisms 252. For example, retainer bracket 242 may include recesses with opposing C-channels (not shown) similar to recess 178. and the opposing C-channels 180 described above with respect to retainer 20. The retainer bracket 242 may also include recessed obstacles (not shown) similar to the recessed obstacle 182 described above with respect to the retainer 20 to respectively accommodate locking elements of the clamping mechanism 252. Preferably, the clamping bars 254 of the clamping mechanisms 252 can be variably locked in different positions, for example, using ratchets 220, as illustrated in Figure 41.

Thus, it can be appreciated that instead of securing the stimulation cable between a sliding clamp bar and a fixed clamp bar, the sliding clamp mechanisms 252 can be slid relative to the disc 244 in order to secure a delivery cable. stimulation between movable gripping bars 254. Significantly, because both clamping mechanisms 252 are slippery relative to disc 244, a plurality of stimulation leads can be secured along any of a plurality of different cords C1-C4 of plug base opening 26, such as illustrated in Figure 46. In particular, since the retainer 240 can be mounted within the plug base opening 26 in some rotational orientation, the cords C1-C4, along which the stimulation leads are secured by the clamping mechanisms 252, can also be in different rotational orientations, as illustrated in Figure 47. Thus, given any number of stimulation leads arranged along a single cord (e.g., any pair of leads), the retainer 240 are able to simultaneously secure the stimulation leads, thereby obviating the need to have separate burr holes, reduce risks to the patient, decrease procedure time, decrease cost to patient, etc.

Although the retainer 240 includes two slide fasteners, retainers constructed in accordance with the present inventions can include more than two slide fasteners. For example, referring to Figures 45a and 45b, another retainer 241 that can be mounted within the opening 26 of the plug base 18 will now be described. As with anterior retainer 240, retainer 241 comprises a retainer bracket 243 that includes a disk 245 and an open slot 247 formed in disk 245 to laterally receive the stimulation lead, thereby allowing retainer 241 to be mounted within. of the plug base opening 26 after the stimulation lead has been inserted through the burr hole. Retainer 240 may include other features, such as a pop-out notch, such as sundial markings, and cable exit grooves (not shown) located in disk 245. Retainer 241 differs from retainer 240 in that it comprises three sliding clamping mechanisms 249, each including a flange 251

ES 2 394 045 T3 with a concave end 253. In another embodiment illustrated in Figure 45c and 45d, the retainer 241 may include four sliding fastening mechanisms 249.

In any embodiment, Each flange 251 slidably engages with disc 245 to laterally slide concave tip 253 radially inward relative to disc 245 and selectively secure the received stimulation lead within cable slot 247 (Figures 45b and 45d) or slide laterally the concave end 253 radially outward from the disc 245 and releases the received stimulation lead within the lead slot 247 (Figures 45a and 45c). The concave extremities 253 are opposite each other to hold the stimulation wire therebetween. Each clamping mechanism 253 may alternatively include a U-shaped ledge, a resilient arm, a locking tab, and an arm obstacle (not all shown) similar to a U-shaped ledge 186, resilient arm 200, locking flange 202 and arm obstacle 220 described above with respect to retainer 20.

In an alternate embodiment illustrated in Figures 50 and 51, multiple opposing sets of slide clamping mechanisms 255 can be independently slid relative to each other to selectively secure multiple received stimulation leads within the lead slot (Figure 45f) or release the leads. of stimulation received within the cable slot (Figures 45e).

While the anterior retainers 20, 230, 240 include fixed open wire slots for receiving stimulation leads, the retainers may have wire slots that open and close alternately. For example, as illustrated in Figures 48 and 49, an articulated retainer 260 will now be described. Retainer 260 is similar to retainer 240 illustrated in Figure 45, except that it comprises a retainer bracket 262 that includes a pair of hemispherical disc portions 264, a pair of slide clamping mechanisms 266, and a coupled link 268. to disc parts 264, such that the disc portions 264 may alternately hinge opening (Figure 48) to open a lead slot 270 to laterally receive the stimulation lead and hinge closed (Figure 49) to close the lead slot 270 around the lead stimulation. In this manner, the retainer 260 can still be mounted within the plug base opening 26 after the stimulation wire has been inserted through the burr hole without sacrificing the structural integrity typically associated with a disc that is fully closed around. of its circumference. The retainer 240 further comprises a locking mechanism 272 (best shown in Figure 48) in the form of a protrusion at the end of one of the 264 disc portions and a corresponding recess (not shown) at the end of the other. disc portion 264, such that cable slot 270 remains closed when clamping mechanisms 266 are manipulated. The clamping mechanisms 266 function in the same manner as the clamping mechanisms 252 described above to selectively secure the received stimulation lead within the lead slot 268 or to release the received stimulation lead within the lead slot 268.

Other types of cable retainers are also contemplated by the present inventions. For example, referring to Figures 50 and 51, another cable retainer 280 comprises a retainer bracket 282 configured to be mounted within the opening of the plug base 18, and a fastener 284 configured to mate with the retainer bracket. 282. In the illustrated embodiment, the retaining bracket 282 comprises a semi-circular rim 286, a fixed clamping bar 288 located in the diameter of the semi-circular rim 286, and a pair of opposing annular C-channels 290 extending around the circumference of the semi-circular rim. 286. Retainer 280 may include other features, such as a jump-out notch, such as sundial markings, and cable exit grooves (not shown) located in semi-circular flange 286.

Fastener 284 comprises a transverse member 292 and a clamping bar 294 disposed on transverse member 292. Thus, when fastener 294 is paired with retaining bracket 292, the stimulation lead will be secured between a clamping surface 296. of the retaining bracket 282 (and in particular the fixed clamping bar 288) and a clamping surface 298 of the clamp 284 (and in particular the movable clamping bar 294). Fastener 284 is configured to mate with retention bracket 282 in an interference arrangement. To this end, fastener 284 has a pair of elastic opposing arms 300 that extend from transverse member 292. Arms 300 are configured to slideably engage respective C-channels 290 located in semi-circular rim 286. Thus, fastener 284 can be paired with retention bracket 282 by inserting the respective arms 300 of fastener 284 into the C-channels 290. In particular, the resilience of arms 300 allows them to flex outward as they are inserted into the C 290 channels, and once fully inserted, flex back to normal shape to grip the C 290 channels.

The fastener 284 further comprises a pair of locking elements, and, in particular, a pair of flanges 302 respectively arranged at the ends of the arms 300, in such a way that when the arms 300 are fully inserted into the C-channels 290, flanges 302 engage the ends of opposing C-channels 290 to lock fastener 284 relative to retention bracket 282. Arms 300 can be moved toward each other away from C-channels 290 to disengage locking tabs 302 from opposing C-channels 290, thereby allowing fastener 284 to be removed from retaining bracket 282.

ES 2 394 045 T3 fixer 284 further comprises a pair of obstacles 304 located between the transverse member 292 and the respective elastic arms 300 that abut the fixed clamping bar 288 and the front of the C-channels 290 when the fixer 284 is paired with retaining bracket 282. In this manner, clamp bar 294 of fixator 284 is prevented from moving past a certain point, thereby preventing damage to the stimulation lead.

Referring to Figures 52 and 53, details of cap 22 will now be described. Cap 22 is configured to mount to cap base 18 over retainer 20, thereby securing the stimulation lead, as well as closing the hole. trephine. Cap 22 may be comprised of a suitable hard or soft biocompatible material, such as titanium, a hard polymer, a soft polymer, Silastic, elastomer, or any other combination thereof. The cap 22 may be composed of PEEK, although the durability of the cap 22 may not be as important as the other components of the burr hole plug 16.

Cap 22 comprises a cap-like circular body 310 having an edge 312 sized and shaped to be disposed within cap base opening 26 and to rest on retaining disc 164. To accommodate locking ramps 48 located On the inner surface 46 of the cap base body 24, the cap 22 includes a plurality of recesses 314 located on the outer surface of the rim 312. The number and circumferential spacing of the recesses 314 coincide with the number and spacing of the locking ramps 48, such that each ramp 48 is received in a corresponding recess 314 when the cap 22 is mounted on the plug base 18 .

Cap 22 further comprises a plurality of winged flanges 316 (in this case, two) configured to be received in corresponding locking recesses 42 located in cap base body 24 (shown in Figure 8) in an arrangement with interference, and, in particular, a snap-fit ​​arrangement, thereby preventing rotation of cap 22, as well as ensuring that cap 22 is securely mounted on cap base 18. Alternatively, other locking mechanisms, such as snaps, hooks, grips, projections, etc., or any other mechanical structure may be used to lock the cap 22 in place. Cap 22 also comprises a plurality of pop-out notches 318 (in this case, two) formed on edge 312 of cap body 310, such that when cap 22 is mounted and secured in cap base 18, One of the jump-out notches 318 corresponds to the jump-out recess 38 located on the inner edge 40 of the ring-shaped plug body 24 (shown in Figure 8). Thus, the cap 22 can be conveniently removed from the cap base 18 by inserting a tool into the outward snap recess 38 and into the corresponding outward snap notch 318 in the cap 22.

Cap 22 further comprises a plurality of cable tie grooves 320 (in this case four) located on the bottom surface of cap 22 and extending through edge 312. The number and circumferential spacing of the cable clamp grooves 320 matches the number and spacing of the cable outlet grooves 36 located in the plug base 18 (shown in Figure 8), such that the grooves 320 Cable tie grips will be circumferentially aligned and immediately radial adjacent the cable exit grooves 36. In this manner, when the cap 22 is mounted on the cap base 18, the stimulation lead will seat firmly within the selected lead clamp groove 320. In this way, the selected lead clamp groove 320 will apply downward pressure to the stimulation lead, causing the corresponding lead outlet groove 36 to counteract with upward pressure on the stimulation lead, thereby providing a tight fit. by secure friction between the stimulation lead and the lead outlet and lead clamp grooves 36, 320.

Having described the burr hole plug 16, various tools that can be used to install a burr hole plug in a burr hole will now be described. Referring to Figures 5456, an embodiment of a plug base holding tool 330 configured to hold the plug base 18 to aid in its mounting to the skull of the patient will be described. The plug base holding tool 330 generally comprises a burr hole cover 332, a handle 334 mounted on the burr hole cover 332, and a pair of screw holder arms 336 extending in opposite directions from the socket. handle 334. Tool 330 can be composed of a suitable, rigid and robust material, such as stainless steel or a durable plastic, such as polypropylene, polycarbonate, or even PEEK if very little deformation is desired. The tool 330, or at least the structural part of the tool, may be of a single body design, thereby increasing the strength and robustness of the tool 330.

The burr hole cover 332 has a cap shape that has an opening geometrically similar to the opening 26 in the plug base 16 (in this case, circular) and is dimensioned to fit into and completely cover the base opening 26 of the burr hole. plug. The lip of the burr hole cover 332 may rest on annular projections of the plug base 16 in the same manner that the retainer rests on the annular projections described above. This minimizes any potential for dirt, such as screws, to fall through the plug base opening 26 and into the burr hole, or accidental slipping of tools, such as a screwdriver, into the burr hole. . In an optional embodiment, the cover 332 of

ES 2 394 045 T3 burr hole 332 includes features, such as spring clips, keyways, set screws, adhesive, suction holes, threads, etc., that engage the plug base 16 in a manner that ensures tightness. burr hole cover 332 within aperture 26 and also allows burr hole cover 332 332 to be removed from plug base 16 after plug base 16 is anchored in the skull of the patient. Alternatively, the tool 330 may be shaped in a way that its center of gravity is positioned such that the tool 330 remains on a flat surface without being attached to the plug base 16 (ie, it does not fall off). In the case where plug base 16 does not include self-centering tabs, tool 330 may include centering tabs (not shown) that extend downwardly from cover 332, through opening 26 in the cap. plug base 16, and in the burr hole, in order to center the plug base 16 with respect to the burr hole.

The handle 334 extends laterally away from the burr hole cover 332, and thus the burr hole, so as not to interfere with the placement, viewing, alignment, and anchoring of the plug base 16 in the burr hole. The handle 334 is shaped to allow the clinician to grip the handle in a more ergonomic manner. For example, handle profile 334 widens outward as handle 334 extends laterally from burr hole cover 332 to allow handle 334 to be more easily grasped. In addition, the handle 334 includes relief features (in this case, grooves with a criss-cross pattern) to facilitate grasping the handle 334, which can be important in a slippery environment (such as a doctor wearing wet gloves). In an alternate embodiment illustrated in Figures 57 and 58, two opposing grips 334 extend laterally from burr hole cover 332 in opposite directions, thereby allowing the clinician the option of holding tool 330 from two different sides ( e.g. in case the doctor does not have access to one side of the burr hole). Additional grips (not shown) may be provided (eg, two opposing grips oriented ninety degrees from grips 334) to provide additional grip options for the clinician.

In the illustrated embodiment, burr hole cover 304 includes a pair of recesses 338 formed in its upper surface to accommodate laterally extending screw holding arms 336. Screw support arms 336 include collars 340 that are spaced from one another such that they respectively align with screw holes 34 located in plug base 18 when burr hole cover 332 is mounted within the plug base opening 26. In this way, screws 15 can be precisely inserted through collars 340 and aligned with screw holes 34 (shown in Figure 8) in plug base 18, such that screws 15 can be conveniently screwed onto the patient's skull. Preferably, the openings within the collars 340 are slightly larger than the diameter of the screw heads, such that the screw heads can be recessed in the collars 340, thereby allowing the screws 15 to be fully threaded into. the skull without removing the tool. In addition to aligning screws 15 with screw holes 34 in plug base 18, collars 340 also limit screwdriver slippage, should it occur.

Referring to Figures 59-61, another embodiment of a plug base holding tool 350 configured to be connected to the plug base 18 to aid in its mounting in the patient's skull will be described. The plug base holding tool 350 generally comprises a burr hole cover 352, a handle 354 mounted to the burr hole cover 352, and a pair of screw holder mechanisms 356 that extend in opposite directions from the burr hole cover 352. The tool 350 can be composed of a suitable, rigid and robust material, such as stainless steel or a durable plastic, such as polypropylene, polycarbonate, or even PEEK if very little deformation is desired. The tool 350, or at least the structural part of the tool, may be of a single body design, thereby increasing the strength and robustness of the tool 350.

Burr hole cover 352 has a cylindrical shape having a diameter substantially the same as the diameter of plug base 18 opening 26 (in this case circular) and is dimensioned to completely cover plug base opening 26. This minimizes any potential for dirt, such as screws, to fall through the plug base opening 26 and into the burr hole, or accidental slipping of tools, such as a screwdriver, into the burr hole. . Tool 350 includes a plurality of centering tabs 358 that extend downwardly from burr hole cover 352 such that centering tabs 358 rest against inner surface 46 of plug base 18 when cover 352 The burr hole is mounted within the plug base opening 26. In the illustrated embodiment, two pairs of centering tabs 358 (only one pair shown) are disposed opposite each other circumferentially.

The tool 350 includes several features that engage the plug base 18 in a manner that secures the burr hole cover 352 within the opening 26 and also allows the burr hole cover 352 to be removed from the burr base 18. plug after the plug base 18 is anchored in the skull of the patient. In particular, tool 350 comprises upper grip tabs 360 and lower grip tabs 362 arranged in a manner such that when tool 350 is disposed within opening 26 of plug base 18, the thickness of the base 18 plug is arranged between the grip tabs

ES 2 394 045 T3

360, 362, so that the plug base 18 is gripped from above and below; that is, the upper gripping tabs 360 have lower surfaces that frictionally grip the upper surface 28 of the cap base 18, and the lower grip tabs 362 have upper surfaces that frictionally grip the lower surface 30 of the plug base 18. The upper surfaces of the lower gripping flanges 362 may be slightly convex, so that they perfectly mate with the slightly concave lower surface 30 of the plug base 18.

In the illustrated embodiment, there are two upper gripping tabs 360 (only one shown) that extend radially and are circumferentially disposed on opposite sides of the outer surface of the burr hole cover 352, and two pairs of lower gripping tabs. 362 (only one pair shown) that extend radially and are disposed circumferentially on opposite sides of respective pairs of centering tabs 358. Each pair of lower gripping flanges 362 rides circumferentially on the respective upper gripping flange 360 ​​to securely engage a circumferential portion of the plug base 18 therebetween. Thus, it can be appreciated that the grip tabs 360, 362 allow the tool 350 to grip and retract the plug base 18, as well as prevent the tool 350 from being pulled away from the plug base 18 when anchoring the plug base 18. plug to the patient's skull.

Tool 350 also comprises a plurality of rotating alignment tabs 364 extending radially from the outer surface of burr hole cover 352 to rotatably align screw holding mechanisms 356 with clamping holes 34 in base 18 of plug, as well as to prevent tool 350 from rotating or rotating in opening 26 of plug base 18. In the illustrated embodiment, two rotating alignment tabs 364 are disposed circumferentially opposite each other, and are sized and shaped to be securely disposed within the cap locking recesses 42 in the cap base 18. Alternatively, tool 350 may include rotatable alignment tabs (not shown) that are sized and shaped to be securely disposed within cable outlet grooves 36 of plug base 18.

Handle 354 is shaped such that the clinician can grip it ergonomically to prevent tool 350 and plug base 18 from moving when plug base 18 is anchored in the skull of the patient. Handle 354 can have any of a variety of shapes. In the embodiment illustrated in Figures 59-61, the handle 354 is butterfly shaped, thereby providing a wider base for the clinician to apply a downward force on the plug base 18. The symmetry of handle 354 allows the downward force to be applied equally to each side of plug base 18, thereby preventing tool 350 and plug base 18 from swinging back and forth. The butterfly shape of the handle 354 also prevents the physician's hand from creating an obstruction for the clamping holes 34 of the plug base 18, the screw alignment mechanisms 356, or the screwdriver.

Referring further to Figures 62-64, the screw alignment mechanisms 356 respectively include two arms 366 and collars 368 disposed at the ends of the arms 368. The collars 368 are spaced apart from each other, such that they are aligned respectively. with the clamping holes 34 located in the plug base 18 when the burr hole cover 352 is mounted within the plug base opening 26. In this way, screws 15 can be precisely inserted through collars 368 and aligned with clamping holes 34 in plug base 18, such that screws 15 can be conveniently threaded into the patient's skull. . Each collar 368 has a large diameter upper bore 370 and a small diameter lower bore 372 in communication with the upper bore 370. The diameter of the lower bore 372 is equal to the outer diameter of the head of the screw 15, such that the screw 15 remains constantly centered with the respective clamping hole 34 in the base 18 of the plug when the head of the screw 15 passes to through perforation 372.

Each screw alignment mechanism 356 includes an insert 374 disposed within the upper bore 370 of the collar 368. The insert 374 is comprised of a flexible material, such as silicone. The insert 374 takes the form of a ring-like structure or gasket that firmly holds and centers the respective screw 15 within the collar 368. In particular, as best shown in Figures 61 and 63, the insert 374 includes an outer ring 376 and an inner ring 378, disposed concentrically within the outer ring 376. Thus, the insert 374 effectively reduces the diameter of the upper bore 370, thereby facilitating the centering of the respective screw 15 before the head of the screw 15 passes into the lower bore 372. The flexibility of insert 374 allows the head of screw 15, which is larger in diameter than the inner diameter of inner ring 378, to pass through inner ring 378. Insert 374 also centers the screwdriver (not shown ), when it is inserted into the lower bore 372, and when it is removed and re-inserted into the lower bore 372. In the latter case, this facilitates the alignment of the screwdriver with the screw head 15. Optionally, there may be a metal insert (not shown) within the collar 368 to prevent the plastic from being scraped off.

As best shown in Figures 63 and 64, each collar 368 has a protrusion 380 between upper and lower perforations 370, 372, and a pair of circumferentially disposed grooves 382 formed through the

ES 2 394 045 T3 protrusion 380, and the respective insert 374 includes a pair of circumferentially opposed retaining flanges 384 extending from the bottom of the outer ring 376. Each flange 384 extends downward from the bottom of the outer ring 376 and then radially outward. Thus, when insert 374 is mounted within upper bore 370, tabs 384 of insert 374 are respectively disposed through slots 382 in shoulder 380 of collar 368, thereby firmly retaining the piece. inserted 374 with upper perforation 370.

In an alternate embodiment illustrated in Figures 65 and 66, the tool 350 comprises a screw alignment mechanism 386 that includes a collar 388 having a bore 390 with a uniform diameter extending therebetween. The screw alignment mechanism 386 also comprises an insert 392 which, like the insert 374 described above, is comprised of a flexible and bendable material, eg, silicone. Insert 392 has an annular upper flange 394, an annular lower flange 396, and a smaller diameter cylindrical portion 398 that extends between the upper and lower annular flange 394, 396. Insert 392 is configured to be mounted within collar 388, such that cylindrical portion 398 is disposed within bore 390 of collar 368, and upper and lower annular flanges 394, 396 are respectively disposed in the upper and lower surfaces of collar 368 to firmly retain cylindrical portion 398 within bore 390.

As best shown in Figure 66, insert 392 includes a plurality of inner rings 400 (in this case, two) disposed concentrically along the length of cylindrical portion 398. Thus, the inner diameters of the Inner rings 400 are equal to the outer diameter of screw 15, thereby facilitating centering of respective screw 15 within bore 390 of collar 388. The flexibility of insert 392 allows the head of screw 15, which is larger in diameter than the inner diameter of inner ring 400, to pass through inner ring 400. Insert 392 also centers the screwdriver (not shown ), when it is inserted into bore 390, and when it is removed and re-inserted into bore 390. In the latter case, this facilitates alignment of the screwdriver with the screw head 15.

In another alternate embodiment illustrated in Figures 67 and 68, the tool 350 comprises a screw alignment mechanism 406 that includes the collar 388 described above and a plurality of flanges or ridges 408 that extend radially inwardly around the inner circumference of the collar 388 in bore 390. Radial flanges 408 can be formed as a single-body structure with collar 388, and are sufficiently thin such that they will bend without breaking when screw 15 passes through bore 390 in collar 388. Alternatively, the Radial flanges 408 may be composed of a material that is more flexible than the material of which collar 368 is composed. As can be appreciated, the radial flanges 408 effectively reduce the diameter of the bore 390 of the collar 368, thereby facilitating the centering of the respective screw 15 within the bore 390. The flexibility of the radial flanges 408 allows the head of the screw 15 pass through bore 390. Radial flanges 408 can also center the screwdriver (not shown) in the same manner as inner rings 400 of addition 392 described above. In the illustrated embodiment, radial flanges 408 are arranged in multiple layers (in this case two layers of four flanges each) extending inwardly along the length of collar 368 within perforation 390.

Referring now to Figures 70 and 71, an embodiment of a retainer holding tool 430 configured to mount retainer 20 within opening 26 of plug base 18 (shown in Figure 8) will now be described. The retainer holding tool 430 generally comprises a handle 432 and a plurality of fingers 434 that extend from the handle 432 and are configured to engage connection points 436 on the upper surface 171 of the retaining disc 164. The tool 430 It can be composed of a suitable, rigid and robust material such as stainless steel or a durable plastic such as polypropylene, polycarbonate or even PEEK if very little deformation is desired. Handle 432 is angled relative to fingers 434 to facilitate manipulation, direction, and placement of retainer 20 in tight spaces; for example, due to its angle relative to the plane of the retainer 20 it supports, the movement of the handle 432 cannot be obstructed by equipment immediately above the burr hole.

The distal ends of the fingers 434, and thus the contact points 436 on the upper surface 171 of the retaining disc 164, are spaced from each other in a manner that substantially distributes any downward force applied by the tool 430 through from the plane of the retaining disc 164 when mounted within the plug base opening 26. In the embodiment illustrated in Figures 70 and 71, the distal ends of three fingers 434 are engaged with the contact points 436, and in particular small recesses or possibly holes, formed in the upper surface 171 of the retaining disc 164. The fingers 434 of tool 430 are configured to engage recesses 436 with an interference arrangement, eg, a snap fit arrangement. As will be described in further detail below, the holding force between the fingers 434 of the tool 430 and the retainer 20 should be less than the holding force between the retainer 20 and the plug base 18, so that the tool 430 can be easily removed from retainer 20 when mounted within plug base 18.

ES 2 394 045 T3

Preferably, this interference arrangement is sufficient to provide a firm engagement between tool 430 and retainer 20, but should be capable of being overcome after retainer 20 is mounted within plug base 18 so that the tool 430 can be easily removed from retainer 20, while leaving retainer 20 firmly mounted within plug base 18. For example, as illustrated in Figure 72, the recesses 436 may be formed entirely through the thickness of the retaining disc 164, and the distal ends of the fingers 434 may have barbs 438 that extend through the recesses 436 and engage the bottom surface of retaining disc 164. The prongs 438 must be sized such that they remain within the recesses 436 during normal handling, direction and placement of the retainer 20, but must be capable of being displaced through the recesses 436 when the tool 430 is removed from retainer 20; that is, the upward force necessary to pull the barbs 438 through the recesses 436 must be less than the upward force necessary to remove the firmly mounted retainer 20 from the plug base 18. The portions of the fingers 434 above the recesses 436 may be widened or enlarged to provide a more stable base that more evenly distributes the downward force over the upper surface 171 of the retaining disc 164.

In a preferred embodiment, fingers 434 are resiliently flexible so that they store a spring force when engaged with recesses 436 in retaining disc 164. In this case, the spacing between the distal ends of fingers 434, in the absence of any lateral force, it is slightly less than the spacing between the recesses 436 in the retaining disc 164. In this manner, fingers 434 will act as biased springs when engaged with recesses 436, thereby providing additional gripping force that reinforces engagement with retainer 20. That is, the fingers 434 will spread slightly outward when positioned within the recesses 436, thereby creating a spring force that laterally biases or biases the fingers 434 into the recesses 436 to create a frictional force that facilitates movement. coupling between the fingers 434 and the recesses 436. The fingers 434, as well as the handle 432, may be composed of a suitable elastic material, such as polypropylene, polycarbonate, and the like. Alternatively, tool 430 may be provided with a separate spring-like mechanism 440 engaged between fingers 434, as illustrated in Figure 71. In alternative embodiments, the proximal end of tool 430 may be designed to perform another function, such as moving the clamping mechanism 162 or popping the retainer 20 out of the plug base 18.

Referring next to Figures 73-75, another embodiment of a retainer holding tool 450 configured to mount retainer 20 within opening 26 of plug base 18 will now be described. Holding tool 450 is specifically designed not to interfere with the stimulation lead when retainer 20 is mounted within plug base opening 26. In particular, the holding tool 450 generally comprises a handle 452, a C-shaped rim 454, and pins 456 extending downwardly from the C-shaped rim 454. The tool 450 may be composed of a suitable material, rigid and robust, such as stainless steel or a durable plastic, such as polypropylene, polycarbonate or even PEEK if very little deformation is desired.

In the illustrated embodiment, two C-shaped rim pins 456 are provided, one located at one end of the C-shaped rim 454 and the other located near the center of the C-shaped rim 454. Optionally, one may be provided. third peg (not shown) at the other end of the 454 C-shaped flange. The pins 456 are spaced from one another such that they engage with contact points, and in particular with corresponding recesses or holes 458 (only one is shown in Figure 75) formed in the upper surface 171 of the retaining disc 164 The pins 456 of the tool 430 are configured to engage the recesses 458 with an interference arrangement, eg, a friction fit. The retention force between the pins 456 of the tool 430 and the retainer 20 should be less than the retention force between the retainer 20 and the plug base 18, so that the tool 450 can be easily removed from the retainer 20 when it is in place. mounted within plug base 18. As with the previously described fingers 434, the spacing between the pins 456 may be slightly less than the spacing between the recesses 458 to increase the frictional force between the pins 456 and the recesses 458; that is, a spring force is stored in the pins 456 to install them inwardly when engaged with the recesses 458. Optionally, to reinforce interference fit, pins 456 may have barbs (not shown) and recesses 458 may be formed entirely through the thickness of disk 164 in the same manner as described above with respect to tool 430.

As can be seen in Figure 75, the C-shaped flange 454 accommodates the stimulation lead exiting the burr hole. That is, the C-shaped rim 454 is sized and shaped such that it extends around or near the outer periphery of disk 164 without obstructing the clamping groove 166, and corresponding recesses 458 are similarly disposed on or near the outer periphery of disk 164. Tool 450 further comprises a support flange 460 located at the end of C-shaped flange 454 opposite pin 456, thereby facilitating the application of uniform pressure to disk 164 when mounted within aperture 26 of the plug base by tool 450. In an optional embodiment, U-shaped flange 454 is configured to rotate about the axis of handle 452 (shown by arrow in Figure 74).

ES 2 394 045 T3

To this end, and as best shown in Figure 76, the tool 450 further comprises a collar 462 mounted perpendicularly to the C-shaped flange 454 (both shown in imaginary line), and the handle 452 includes a reduced diameter shoulder. 464 received within collar 462 so that collar 462, and thus C-shaped flange 454, can rotate around handle 452. The reduced diameter shoulder 464 of the handle 452 is configured to interfere with the collar 462 such that the collar 462 and the C-shaped flange 454 do not separate when the pins 456 are separated from the corresponding recesses 458 in the disc 164. To this end, the tool 450 further comprises a movable pin 466 disposed within the side wall of the collar, and the reduced diameter shoulder 464 has an annular recess 468 that receives the pin 466. The pin 466 may be composed of a suitable material , for example, stainless steel. It can be appreciated that pin 466 can slide with annular recess 468, thereby allowing collar 462, and thus C-shaped flange 454, to rotate about the axis of handle 452. Because the pin 466 is seated firmly within annular recess 468, however, C-shaped flange 454 cannot be removed from handle 452 without using a significant amount of axial force. In particular, pin 466 frictionally engages annular recess 468 such that C-shaped flange 454 does not rotate freely; that is, the C-shaped rim 454 will not rotate relative to the handle 452 without applying deliberate force to the C-shaped rim, eg, by being rotated by hand.

In particular, handle 452 is angled relative to C-flange 454 to facilitate manipulation, direction, and placement of retainer 20 in tight spaces. That is, due to its angle relative to the plane of the retainer 20 that it supports, the movement of the handle 452 cannot be obstructed by equipment immediately above the burr hole. To this end, the distal end of handle 452 on which collar 462 is mounted has a curve (eg, a 45 degree or 60 degree angle between collar 462 and handle 452) to effect angulation of handle 452 relative to C-rim 454. The distal end of handle 452 may optionally be made malleable to allow the clinician to create the optimum angle for insertion of retainer 20 into plug base opening 26. The proximal end of tool 450 may be designed to perform another function, such as locking or unlocking clamping mechanism 162 or popping retainer 20 out of plug base 18. For example, as illustrated in Figure 77, a tapered blunt end 470 may be formed at the proximal end of handle 452.

Referring to Figures 78-80, yet another embodiment of a retainer holding tool 480 configured to mount retainer 20 within opening 26 of plug base 18 (shown in Figure 75) will now be described. Like the tool 450, described above, the tool 480 can be composed of a suitable, rigid and robust material, such as stainless steel or a durable plastic, such as polypropylene, polycarbonate, or even PEEK if very little deformation is desired. Tool 480 comprises a handle 482 having a similar construction to handle 452, and a radially compressible / elastic tip 484 that can be inserted into any of the recesses 458 formed in the upper surface 171 of the retaining disc 164 illustrated in Figure 75. . The outer radius of tip 484 is slightly larger than the radius of each recess 458, such that when tip 484 is inserted into recess 458, tip 484 is radially compressed. The resilience of tip 484 applies a radially outward force against the interior wall of recess 458, thereby creating an interference friction fit that holds retainer 20 in tool 480.

In the illustrated embodiment, the limb 484 takes the form of a spring mechanism, and in particular a spring clamp, which includes a pair of parallel arms 486 that move towards each other from a relaxed position to a compressed position, in response to a compressive force, and move away from each other from the compressed position to the relaxed position in the absence of the compressive force. Tool 480 comprises a collar 488 formed at the distal end of handle 482 to retain tip 484. In particular, collar 488 includes a socket 490 that receives the arms 486 of tip 484 in an interference arrangement. Specifically, the collar 488 is split or bifurcated to form a pair of opposed annular flanges 492 which respectively receive the arms 486 of the end 484 therein. Tip 484 may be arranged as an insert that can be passed through a distal opening 494 of socket 490. Once inserted into socket 494, the resilience of tip 484 will cause arms 486 to be drawn radially outward away from each other. one from the other until firm contact with the respective annular rim 492, thereby mounting the tip 484 on the handle 482. In this state, the tip 484 will be partially radially compressed. When tip 484 is inserted into recess 486 in retaining disc 164, tip 484 will be further radially compressed within recess 486 to create the aforementioned frictional fit. To prevent end 484 from moving axially out of socket 490 during such compression, end 484 further comprises a pair of radially outward flanges 496 respectively formed at the ends of arms 484. The distal end of handle 482 further includes corresponding recesses 498 for receiving and holding tabs 496 therein.

Having described the structure and function of the burr hole plug 16 and the tools used with burr hole plugs in a burr hole, a method for mounting the burr hole plug 16 in a burr hole will now be described. Referring first to Figure 81, the plug base 18 is positioned on top of the skull 6 of the patient. In particular, the centering tabs 32 located on the plug base 18

ES 2 394 045 T3 can be disposed within the burr hole 5, thereby centering the plug base 18 around the burr hole 5. If the recessed plug base 57 illustrated in Figures 10-13 is used, the annular flange 45 will also be recessed in the burr hole 5, as illustrated in Figure 82, to allow the retainer 20 to be recessed further down. in the burr hole. Referring back to Figure 81, plug base 18 is then anchored to skull 6 using screws 15 inserted through screw holes 34 in plug base 18. Any of the plug base anchor tools 300 (Figures 54-58), 350 (Figures 59-68) or 410 (Figure 69) can be used to align screws 15 with screw holes 34 while covering the opening 26 on the plug base 18, and if self-centering tabs are not provided on the plug base 18, they can help center the plug base 18 with respect to the burr hole 5.

Then, as illustrated in Figure 83, the stimulation lead 12 is introduced through the plug base opening 26, through the burr hole 5 and into the brain tissue, such that the electrodes (are not shown) of the stimulation lead 12 are adjacent to the target site. In the case where the slotted plug base 58 illustrated in Figure 16 is used, the stimulation lead 12 may first be inserted through the burr hole 5, the stimulation lead 12 may be inserted laterally into the slot 66 of the plug base 58, as illustrated in Figure 84, and then the plug base 58 can be arranged and anchored on the skull 6 in the same manner as described above with respect to Figure 81. In the case where the split plug base 78 illustrated in Figures 17 and 18 is used, the stimulation wire 12 may first be inserted through the burr hole 5 and the first plug base portion 80 may be positioned. next to one side of the stimulation cable 12, the second plug base part 82 can be located next to the other side of the stimulation cable 12, and then the first and second parts 80, 82 The plug base may be paired together to integrate the plug base 78. This can be accomplished by placing the first plug base part 80 in the skull 6 next to one side of the stimulation lead 12, as illustrated in Figure 85, and then placing the second plug base part 82 in the first part 80. plug base next to the other side of stimulation lead 12, as illustrated in Figure 86. If the first and second plug base portions 80, 82 are initially coupled together using the mating pins 100 and recesses 102, the pins 100 may be skewed prior to mating the base portions 80, 82 together.

After matching the base portions 80, 82 together, the integrated plug base 78 can then be anchored to the skull 6 in the same manner as described above with respect to Figure 81. Of course, the plug slot base 58 or the base Plug portion 78 may be anchored to skull 6 before stimulation wire 12 is inserted through burr hole 5 in the same manner as described above with respect to plug base 18.

After plug base 18 has been anchored to skull 6 and stimulation wire 12 inserted through burr hole 5 and appropriately positioned adjacent to the target site, retainer 20 is mounted within plug base opening 26. , as illustrated in Figure 87. Stimulation lead 12 may be laterally inserted into slot 166 formed in retaining disc 164 when retainer 20 is mounted on plug base 18. In the case where the articulated retainer 260 illustrated in Figures 48 and 49 is used, the first and second disc portions 264 can be articulated open to laterally receive the stimulation cable 12, as illustrated in Figure 88, and then be hinged closed to encircle stimulation lead 12, as illustrated in Figure 89. Any of the retainer placement tools 430 (Figures 70-72), 450 (Figures 73-77), or 480 (Figures 78-80) can be used to position and mount the retainer 20 (or retainer 260) within plug base opening 26.

Once retainer 20 (or retainer 230) is firmly mounted within plug base opening 26, retainer 20 is actuated to secure stimulation lead 12 within plug base opening 26, as illustrated in Figure 90. In particular, the clamping mechanism 162 is slid relative to the disc 164 to laterally slide the movable clamping bar 184 towards the fixed clamping bar 176 of the disc 164, thereby securing the stimulation cable 12 received within the slot 166 , and, specifically, clamping the stimulation cable 12 between the movable clamping bar 184 and the fixed clamping bar 176 of the disc 164. Once the stimulation cable 12 is secured, the clamping mechanism locking element 162 can be actuated to lock the movable clamping bar 184 relative to the disc 164. In particular, the movable clamping bar 184 can be slid toward fixed clamping bar 176 until locking flange 202 encounters lowered obstacle 182. Clamping mechanism 162 may be actuated to unlock movable clamping bar 184 relative to disk 164, for example by flexing resilient arm 200 by applying a downward force on recess 212 of locking flange 202 using a tool.

In particular, if the retainer 280 illustrated in Figures 50 and 51 is used, the retainer bracket 282 can be mounted within the opening 26 of the plug base 18, as illustrated in Figure 91, and then the arms 300 of the fixator 284 can be slid into the C-channels 290 located in the semicircular rim 286 until the locking tabs 302 engage the ends of the C-channels 290 to secure the stimulation cable 12 between grab bars 296, 298, as illustrated in Figure 92. If a plurality of stimulation leads 12 are to be secured, retainer 240 illustrated in Figure 45 may be mounted within plug base opening 26 in a manner similar to retainer 20 described above. The clamping mechanisms 252 can then be slid to secure the stimulus cable 12 between the clamping bars 254, as shown

ES 2 394 045 T3 illustrated in Figure 93. As shown, stimulation leads 12 are secured along an off-center chord of plug base opening 26.

After stimulation lead 12 (or leads) is secured within plug base opening 26, stimulation lead 12 is directed radially toward plug base 18 by bending stimulation lead 12 at an angle (by perpendicular example) with respect to an axis of the burr hole 5 and seating the stimulation lead 12 within one of the lead exit grooves 36 located in the plug base 18, as illustrated in Figure 94. If the retainer 230 illustrated in Figure 44 is used, the stimulation lead 12 can be seated within one of the lead exit grooves 232. Then, cap 22 is mounted on cap base 18 over retainer 20, such that stimulation wire 12 is secured between cap base 18 and cap 22, as illustrated in Figure 95. In particular, the cable clamp groove 320 of the cap 22 will capture and apply downward pressure to the stimulation cable 12 to frictionally secure the stimulation cable 12 within the exit groove 36 of the plug base 18.

Although particular embodiments of the present inventions have been shown and described, it will be understood that they are not intended to limit the present inventions to the preferred embodiments, and it will be obvious to those skilled in the art that various changes and modifications can be made without departing from the scope of the present invention. the attached embodiments. Thus, the present inventions are intended to encompass alternatives, modifications, and equivalents, which may be included within the scope as defined by the claims.