Fracture fixation device

c. mason 2,500,9^3

FRACTURE FIXATION DEVICE

Filed March 7, 1945

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ATTORNEY.

Patented Mar. 21, 19S0

2,500,993

UNITED STATES PATENT OFFICE

2,500,993

FRACTURE FIXATION DEVICE

Christopher Mason, Los Angeles, Calif.

Application March 7,1945, Serial No. 581,402

Claims.

This invention relates to the fixation of fractures of the intertrochanteric and subtrochanteric regions of the femur bone and particularly the femur neck, and contemplates more specifically to provide simple, effective and sure means for the internal fixation of such fractures without the need of casts or other external fixation means.

The present invention contemplates the provision of means for holding in fixation, fractures of the neck region of the human femur of all types, including subcapital, transverse and oblique neck fractures and fractures of the intertrochanteric and subtrochanteric regions.

An object of this invention is to provide means of the character indicated which may be set into fixation position without the need for special tools for insertion or removal.

Another object is to provide internal fixation means for the purpose indicated which permits of insertion into position by merely tapping into place, and removal without the need of special tools.

A further object is to provide a device of the indicated type which may be caused to assume a suitable position whereby the portions thereof engaged with both the neck and the proximal fragment of a fractured femur, for instance, are held in suitable fixation.

This invention possesses many other advantages and has other objects which may be made more easily apparent from a consideration of several embodiments of the invention. For this purpose there are shown two forms in the drawings accompanying and forming part of the present specification. These forms will now be described in detail, illustrating the general principles of the Invention; but it is to be understood that this detailed description is not to be taken in a limiting sense, since the scope of the invention is best defined by the appended claims.

Referring to the drawings:

Figure 1 is a semi-diagrammatic front view showing an application of a fracture fixation device according to the present invention;

Figure 2 is a similar side view thereof;

Figure 3 is an enlarged side view taken as indicated by line 3—3 of Figure 2;

Figure 4 is a side view of a fracture fixation device embodying the present invention;

Figure 5 is a plan view thereof;

Figure 6 is a fragmentary detail sectional view showing hinge means employed in the invention, in one position thereof;

(Cl. 128—92)

Figure 7 is a similar view of said hinge means in another position; and,

Figures 8 and 9 are cross sectional detail views as taken on the respective lines 8—8 and 9—3 of Figure 4.

As an example of application of the invention, a human femur is illustrated as providing the means of application of the preferred embodiment of the fracture fixation device.

I As shown, the femur comprises a shank 10, a trochanter it, a neck 12, and a head 13. As well understood, the femur, in the manner of bone structure, has a relatively hard bony cortex surrounding a relatively soft, spongy and cellular i structure. Also, the spongy interior of the femur varies in density, being most dense in the interior of the femur head. The foregoing known structure of the femur has been set forth for the purpose of more clearly demonstrating the

I manner in which the invention utilizes and takes advantage of the femur structure in order to provide safe, sure and efficacious fixation of a fracture thereof.

Also, as shown in Figure 3, the femur may be ί fractured at one or more of the points 14, 15 and 16, the present device being applicable to all of these fracture points by varying the lengths of the nail and/or plate portions.

The herein contemplated device preferably ¹ comprises a member 20, herein termed a nail, a second member 21, herein termed a plate, and preferably includes means such as a hinge or pivot pin 22 whereby said nail and plate may have relative articulation.

The nail 20, of the present embodiment, is V-shaped in cross-section, as best seen in Figure 8, comprising the sides 23 arranged substantially at right angles. This form of section of the nail ^: is preferred to obviate rotation or twist of the nail 40 when being inserted into the spongy parts Of a bone. One end of said nail is preferably sharpened as at 24 and the other end formed with the sides 23 in folded parallel relation as at 25 for connection with the pivot pin 2 2. The nail, at the pivot end, is also preferably provided with an angled edge 26 affording the stop points 27 and 28.

The plate 21 is preferably of arcuate cross section as seen best in Figure 9, and the end thereof, connected to the nail 20 by pivot pin 22, may be arranged to provide parallel walls 29 engaged over end 25 of said nail, both the nail end 25 and the walls 29 having aligned holes for the hinge or pivot pin 22.

It will be noted that the V-section of the nail and the curved section of the plate are oppositely '15

2,600,093 disposed (see Figure 5) and that, with the nail and plate in aligned straight position, the stop point 27 of the nail abuts the extreme end 30 of the plate and that, in this straight condition of the parts, the pivot 22 is on the opposite side of a line 3! drawn between the free ends of the nail and plate from, the stop points 27 and 30. It becomes evident then, that pressure or force applied to the end 32 of the plate, as by means of a hammer or mallet, will be transmitted directly to the sharpened end 24 of the nail to force or drive the same into a mass of the consistency of a bone interior. Thus, in its straight condition, the'device may be applied as intended.

As may be seen from the drawing, limited articulation between the nail 20 and .plate &lt;21 is afforded. The limit of the included .obtuse angle is in the nature of 130° to 135° in accordance with the norminal angle between the neck .and-shank of a femur. The stop point 28, adapted to engage the plate at a point between its end 32 rand the point 33 is provided to limit ..relative movement of .the parts in that direction.

The plate .2.! may be provided with a . plurality of holes such as shown at 33.

Assuming that fixation of a, fracture of the femur at-any of the points 14, 15 or I6 is desired, a flesh incision is made to give access to the affected femoral parts. A hole, approximate^' one-half inch in diameter, is then drilled or chiseled through the cortex of the femur below the greater trochanter and in the line-.of direction of the femoral neck and head. The fracture is reduced with the femur held in suitable . flexion .and neutral rotation. The sharp end 24 of the mail 28 is then inserted in the .drilled.-hole .and -either .pressed for tapped into the spongy -interior of the femoral neck and then Into the denser interior of the femoral· head. .As this phase of the operation proceeds, the proper angular and rotational disposition of the nail may be checked and ascertained by, from -.time, to time, swinging the plate 21 on the pivot pip 22 to cheek its ultimate disposition with respect to. the. proximal portion of the femur. After the nail is in position and firmly inserted into the dense interior of the femoral head, the plate-21 is swung down on its pivot 22 to engage against .distal portions of the femur. -And Anally, screws, such as 34 may be employed for securing the plate -in position, care being taken that these screws are sufficiently .long to pass completely from .side to side of the femur cortex to afford firm,anchorage therein. The incision is then closed-and.dressed.

After the necessary bone knitting period, the fixation device may be removed by simply extracting the screws 34 and exerting a pull on the plate 21, which may be first swung into alignment with the nail portion 23. This can be done with pliers or by inserting an instrument in one of the holes 33 and pulling or tapping the device clear of the femur. When in extended position, the plate serves conveniently as a handle by which the device may be grasped and the ; nail portion pulled from the bone.