WO2021211828A1

WO2021211828A1 - Proximal long femoral nail interlock for fixation of hip fractures

Info

Publication number: WO2021211828A1
Application number: PCT/US2021/027463
Authority: WO
Inventors: Darryl AUSTON
Original assignee: Auston Darryl
Priority date: 2020-04-16
Filing date: 2021-04-15
Publication date: 2021-10-21

Abstract

The present invention facilitates femur repair by providing a long femoral nail capable of receiving a proximal interlock screw. The proximal attachment point allows for fixation of a distal portion of a fractured femur to the femoral nail with a conventional jig. Such saves significant time and reduces the amount of radiation exposure required for insertion of a long femoral nail.

Description

PROXIMAL LONG FEMORAL NAIL INTERLOCK FOR FIXATION OF HIP

FRACTURES

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application No.

63/010,942, filed on April 16, 2020, the entire content of which is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

[0002] Hip fractures sometimes occur among the elderly. Often, those suffering from a hip fracture are relatively frail and have compromised bone structure. Regardless of the patient, it is highly desirable to minimize the time a patient is anesthetized and the time it takes to complete the surgical repair of a hip fracture. It is also desirable to minimize the amount of radiation exposure experienced by the surgical team and by the patient.

[0003] Currently, hip fractures in the elderly are often repaired by mechanically fixing the broken bone with a nail placed within the femoral canal. The exiting techniques uses percutaneous incisions, and fluoroscopic imaging to properly position the nail. Long nails are often used in hip repair. Long nails extend generally from the hip down to the knee within the femur. Long nails advantageously strengthen the entire femur.

[0004] Short nails may also be used. Short nails engage only the proximal portion of the femur and do not provide structural support for the entire femur.

[0005] Both long nails and short nails have a distal interlock screw that rotationally fixes the nail to the femur. Insertion of a distal interlock screw requires drilling an aperture in the femur that aligns with a distal interlock screw aperture in the nail. Once the distal interlock screw is inserted, the femur is prevented from rotating around the longitudinal axis of the nail and from moving axially relative to the nail. Distal interlock screws have been used on long nails since at least the 1980s. [0006] Placement of the distal interlock screw on long nails requires subjecting a patient to additional radiation because the screw must be aligned with a pre-formed hole in the nail. Properly positioning the distal interlock screw to engage the pre-formed hole is done “freehand” and requires repositioning the patient’s broken leg as well as taking multiple fluoroscopic images, which increases the radiation exposure to the patient as well as the surgical team. Moreover, the additional time taken to align the interlock screw with the pre-formed hole in the nail by hand is additional time the patient must be sedated.

[0007] Prior art short nails, typically less than 240mm long, are often implanted with a jig. The jig is used to align distal interlock screws with pre-formed apertures in the distal end of the short nail. Jigs are not used to align digital interlock screws on long nails. Conventional thinking is that a jig cannot be used to place a distal interlocking screw in a long nail, which is typically more than 240mm long.

[0008] A hip fixations system that reduces the time required for surgery and the amount of x-ray radiation needed to properly fix a long nail to the femur is needed.

SUMMARY OF THE INVENTION

[0009] The present invention facilitates femur repair by providing a long femoral nail capable of receiving a proximal interlock screw. The proximal attachment point allows for fixation of a distal portion of a fractured femur to the femoral nail with a conventional jig. Such saves significant time and reduces the amount of radiation exposure required for insertion of a long femoral nail.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] FIG. 1 depicts a prior art long femoral nail.

[0011] FIG. 2 depicts a prior art long femoral nail as inserted in a femur.

[0012] FIG. 3 depicts a long femoral nail disclosing aspects of an embodiment of the present invention. DETAILED DESCRIPTION

[0013] A prior art long nail 10 used to repair a broken femur is depicted in Fig. 1. The nail has a proximal end 12 that is adjacent the hip ball and a distal end 14. A hip ball-connecting aperture 16 is formed in the proximal end 12 of the nail 10 and facilitates connection of the long nail 10 to the hip ball. The proximal end 12 of the nail 10 is enlarged to accommodate hip ball screws (not shown). The long nail 10 has a distal interlock screw apertures 18 at the distal end 14 of the long nail 10. Upon insertion, the distal end 14 of the long nail 10 will be in the femoral canal end adjacent the knee.

[0014] Upon insertion of the prior art long nail 10 into the femoral canal, the proximal end 12 of the long nail 10 extends from the femoral canal and hip ball screws, as shown in Fig. 2, are inserted into the hip ball connecting aperture 16 and are screwed into the hip ball. As depicted in Fig. 2, a fractured femur 20 has a peritrochanteric break A that separates the femur into a proximal portion 24 and a distal portion 22. In the prior art long nail 10, attachment of the distal portion 22 of the femur 20 to the prior art long femoral nail 10 could only be achieved by inserting screws (not shown) in the distal interlock screw apertures 18 at the distal end of the prior art long nail 10. Prior art attachment of the distal end of a long femoral nail 10 to the femur was accomplished by a surgeon using fluoroscopic imagery to align a drill path through the femur with the distal interlock screw aperture(s) 18. This freehand alignment required additional time for the skilled surgeon to properly align and drill through the femur and it required additional radiation exposure for the patient and the operating team.

[0015] An embodiment of the present invention is depicted in Fig. 3. The long nail 10 has a proximal interlock screw aperture 26 located near the proximal end 12 of the long nail 10. The proximal interlock screw aperture 26 is positioned to be sufficiently distal of the proximal end 12 of the nail 10 that an interlock screw (not shown) may engage healthy femoral bone distal of a peritrochanteric fracture. Typically, the proximal interlock screw aperture 20 is about 13 cm from the hip ball-connecting aperture 16. [0016] In practice, the long nail 10, is inserted into the femoral canal. Hip ball screws (not shown) are inserted into the hip ball-connecting aperture 16 and screwed into the hip ball. A jig (not shown) may be used to guide insertion of the hip ball screws. A jig (not shown) may also be used to align a drill path through the femur with the proximal interlock screw aperture 26. This process is relatively quick, does not require repositioning the patient or the broken leg and does not require significant additional radiation. Rather than making a freehand bore through the femur, the drill path is guided by the jig. If the femoral bone adjacent the proximate interlock screw aperture 20 lacks the structural integrity to support an interlock screw, the distal interlock screw aperture(s) 18 at the distal end 14 of the long nail 10 may be used by applying known methods.

[0017] A specific long femoral nail design is used to illustrate an embodiment of the present invention. Those of skill in the art will recognize that the advantages described in the description of the of the shown embodiment could be equally applied to long femoral nails having different designs.

Claims

CLAIMS What is claimed is:

1. A long femoral nail comprising: a proximal end having an enlarged portion and a hip ball-connecting aperture in said enlarged portion; a distal end; a proximal interlock screw aperture positioned distal of said proximal end, said proximal interlock screw aperture positioned to receive an interlock screw guided by a jig connected to said proximal end of said femoral nail; and said femoral nail is more than 240mm long.

2. The long femoral nail of claim 1 wherein said nail is more than 300mm long.

3. The long femoral nail of claim 1 additionally comprising a distal end interlock screw aperture positioned at said distal end of said femoral nail.

4. A femoral nail adapted to extend into a patient’s femoral canal comprising: a proximal end adapted to engage a jig, said proximal end having an enlarged portion having a hip ball-connecting aperture adapted to receive a hip ball-connecting screw; a distal end adapted to be positioned adjacent a patient’s knee upon insertion into said femoral canal; and a proximal interlock screw aperture adapted to receive an interlock screw guided by said jig.

5. The femoral nail of claim 7 additionally comprising a distal interlock screw aperture positioned near said distal end of said femoral nail.

6. The femoral nail of claim 7 wherein said femoral nail is more than 240mm long.

7. The femoral nail of claim 7 wherein said femoral nail is more than 300mm long.

8. A method of stabilizing a femur having a fracture comprising the steps of: placing a femoral nail having a distal end in a femoral canal such that said distal end is adjacent a knee end of said femur; connecting a proximal portion of said fractured femur to said femoral nail, said proximal portion of said femur being proximal of said fracture; using a jig connected to said femoral nail to drill an aperture through a distal portion of said fractured femur, said distal portion of said fractured femur being distal of said fracture; and, connecting said distal portion of said fractured femur to said femoral nail through said aperture.

9. The method of claim 8 wherein said femoral nail is greater than 240mm long.

10. The method of clam 9 wherein said femoral nail is greater than 300mm long.

11. The method of claim 8 wherein said femoral nail has a transverse aperture at said distal end, said transvers aperture adapted to receive a distal interlock screw.

12. The method of claim 8 wherein said connecting said proximal portion of said fractured femur to said femoral nail is accomplished by a screw extending into a hip ball.