Patent Application
20220079635
Proximal femoral fractures are serious injuries that often require surgery to repair. While the type of surgery depends on the location and severity of the fracture, the alignment of the broken bones, and the age and underlying health conditions of the patient, internal nails and screws are frequently used at the site of the fracture.
One aspect of the invention provides a lag-screw-retaining clip including: a medial flange adapted and configured for engagement medially under a head of a laterally inserted screw of a trochanteric fracture nail system; an axial offset member coupled to the medial flange, the axial offset member including: a first, medial end coupled to the medial flange; and a second, lateral end; and a lateral flange coupled to the second, lateral end of the axial offset member. The lateral flange is adapted and configured to rest against a lateral end of a lag screw of the trochanteric fracture nail system and resist lateral movement of the lag screw.
This aspect of the invention can have a variety of embodiments. The medial flange and the lateral flange can be positioned at right angles with respect to the axial offset member. The medial flange can be an annular washer. The lateral flange can be an annular washer. The lateral flange can include a medial boss adapted and configured to engage with the lateral end of the lag screw. The lateral flange can include a complementary geometry adapted and configured to engage with the lateral end of the lag screw.
The lag-screw-retaining clip can consist of a biocompatible material. The biocompatible material can be selected from the group consisting of: titanium alloy, stainless steel, and PEEK.
The axial offset member can include a medial bevel. The axial offset member can include a lateral bevel.
Another aspect of the invention provides a trochanteric fracture nail system including: a trochanteric fracture nail; a lag screw adapted and configured for fixation medially through the trochanteric fracture nail; a laterally inserted screw adapted and configured for fixation medially through the trochanteric fracture nail; and the lag-screw-retaining clip as described herein.
This aspect of the invention can have a variety of embodiments. The lag screw and the laterally inserted screw can be adapted for fixation parallel to each other. The trochanteric fracture nail can include two parallel bores.
The trochanteric fracture nail system can further include a guide comprising parallel bores for placement of the lag screw and the laterally inserted screw through a subject's femur and through the trochanteric fracture nail. The guide can be adapted and configured to engage with a superior end of the trochanteric fracture nail.
Another aspect of the invention provides a method of treating a proximal femoral fracture in a subject in need of treatment. The method includes: placing a trochanteric fracture nail axially within the subject's femur; driving a lag screw through the femur and through the trochanteric fracture nail; placing the lateral flange of the lag-screw-retaining clip as described herein laterally over a lateral end of the lag screw such that the medial flange lies medial to the lateral flange; and driving a laterally inserted screw through the femur and through the trochanteric fracture nail such that: the medial flange of the lag-screw-retaining clip is laterally impinged by the laterally inserted screw; and the lateral flange of the lag-screw-retaining clip laterally impinges the lag screw.
For a fuller understanding of the nature and desired objects of the present invention, reference is made to the following detailed description taken in conjunction with the accompanying drawing figures wherein like reference characters denote corresponding parts throughout the several views.
The instant invention is most clearly understood with reference to the following definitions.
As used herein, the singular form “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise.
As used in the specification and claims, the terms “comprises,” “comprising,” “containing,” “having,” and the like can have the meaning ascribed to them in U.S. patent law and can mean “includes,” “including,” and the like.
As used herein, the term “later” refers to a component that is located relatively away from the midline of a subject's body.
As used herein, the term “medial” refers to a component that is located relatively toward the midline of a subject's body.
Unless specifically stated or obvious from context, the term “or,” as used herein, is understood to be inclusive.
Trochanteric fracture nails are frequently used in the treatment of a proximal femoral fracture. Trochanteric fracture nails, including a lagscrew, are universally designed as dynamic constructs allowing the lag screw, embedded in the femoral head of a patient, to collapse down into the nail as the fracture compresses. In one aspect, the present invention relates to locking in a nail that already has (or is capable of having) a second screw in the proximal nail shaft such as a laterally inserted screw. In some embodiments, the second screw is used as a mounting point for a device (e.g., an off-set clip) that protrudes to cover or make contact with a lateral aspect of the lag-screw in a way that prevents the lag-screw from sliding laterally. The attachment of the off-set clip to the laterally inserted screw prevents or limits the lag-screw from moving without shifting the laterally inserted screw, which may be threaded into the nail for resistance.
In some aspects, the present invention relates to a lag-screw-retaining clip. In another aspect, the present invention relates to a trochanteric fracture nail system comprising a lag-screw-retaining clip which limits the lag screw from moving without shifting the laterally inserted screw. In yet another aspect, the present invention relates to method of treating a proximal femoral fracture in a subject in need thereof.
Referring to
Lag screw 104 and laterally inserted screw 106 can be adapted for fixation parallel to each other. In some embodiments, trochanteric fracture nail 102 comprises a first parallel bore 108 and a second parallel bore 110. Lag screw 104 may be inserted through second parallel bore 110 and laterally inserted screw 106 may be inserted through first parallel bore 108 such that trochanteric fracture nail system 100 is configured for placement through the femur of a subject in need thereof. In certain embodiments, trochanteric fracture nail 102 further comprises a third bore 112 distal to first parallel bore 108 and second parallel bore 110 (
In some embodiments, trochanteric fracture nail system 100 further comprises a guide.
Referring now to
Medial flange 302 is adapted and configured for engagement medially under a head of laterally inserted screw 106 of trochanteric fracture nail system 100. Lateral flange 306 is adapted and configured to rest against a lateral end of lag screw 104 of trochanteric fracture nail system 100 and resist lateral movement of the lag screw. Lateral flange 306 may further comprise a complementary geometry adapted and configured to engage with the lateral end of lag screw 104.
Medial flange 302 and lateral flange 306 may be positioned at right angles with respect to axial offset member 304. In some embodiments, medial flange 302 is an annular washer. Axial offset member 304 can include a medial bevel 308 and/or a lateral bevel 310 (
The components of trochanteric fracture nail system 100 and lag-screw-retaining clip 300 can be made of any biocompatible material known to a person of skill in the art. In some embodiments, one or more components of nail system 100 or clip 300 are made from a biocompatible metal. Exemplary biocompatible metals include, but are not limited to, stainless steel, titanium, titanium alloy, cobalt-chromium alloy, and combinations thereof In another embodiment, one or more components of nail system 100 or clip 300 are made from a biocompatible plastic. Exemplary biocompatible plastics include, but are not limited to, polyvinyl chloride (PVC), polyethylene, polycarbonate, polyether ether ketone (PEEK), polyetherimide (PEI), polypropylene, polysulfone, polyurethane, and combinations thereof.
A flowchart depicting an exemplary method of treating a proximal femoral fracture in a subject in need thereof is shown in
In step S402, a trochanteric fracture nail is placed axially within a subject's femur (e.g., after boring with a surgical drill bit). The trochanteric fracture nail can be nail 102. In some embodiments, a superior end of nail 102 is engaged with a guide wherein the guide comprises parallel bores.
In step S404, a lag screw is driven through the femur and through the trochanteric fracture nail. In some embodiments, lag screw 104 is driven through trochanteric fracture nail 102. In some embodiments, lag screw 104 is driven through second parallel bore 110 of nail 102. In certain embodiments, the lag screw is advanced through a first parallel bore of a guide that is engaged with a superior end of the trochanteric fracture nail. A guidewire and/or imaging (e.g, fluoroscopy) can be utilized to confirm accurate placement of a bore and associated lag screw.
In step S406, a lag-screw-retaining clip comprising an axial offset member comprising a first, medial end coupled to a medial flange and a second, lateral end coupled to a lateral flange is provided and the medial flange is placed laterally over a lateral end of the lag screw such that the medial flange lies medial to the lateral flange. In some embodiments, the lag-screw-retaining clip is clip 300, comprising medial flange 302, axial offset member 304, and lateral flange 306.
The lag-screw-retaining clip can be placed over the shaft of a laterally inserted screw before insertion into the subject such the lag-screw-retaining clip is secured by the head of the laterally inserted screw. In such an embodiment, the lag-screw-retaining clip can rotate about the laterally inserted screw at least until tightening and/or engagement with the lag screw.
In another embodiment, the lag-screw-retaining clip can be positively attached to the lag screw before advancement of the laterally inserted screw. For example, the lag-screw-retaining clip could be threaded to an end of the lag screw. For example, the lag screw could include male or female threads that permit threaded coupling with the lag-screw-retaining clip, either before or after the lag screw is driven.
In step S408, a laterally inserted screw is driven through the femur and through the trochanteric fracture nail such that: the medial flange of the lag-screw-retaining clip is laterally impinged by the laterally inserted screw and the lateral flange of the lag-screw-retaining clip laterally impinges the lag screw. The laterally inserted screw can be screw 106. In some embodiments, laterally inserted screw 106 is driven through trochanteric fracture nail 102. In some embodiments, laterally inserted screw 106 is driven through first parallel bore 108 of nail 102. The laterally inserted screw can be driven through the nail until the lag-screw-retaining clip contacts and impinges the head of the lag screw. In certain embodiments, the laterally inserted screw is advanced through a second parallel bore of a guide that is engaged with a superior end of the trochanteric fracture nail. A guidewire and/or imaging (e.g, fluoroscopy) can be utilized to confirm accurate placement of a bore and associated laterally inserted screw. The lag-screw-retaining clip can be advanced over one or more guidewires.
In some embodiments, the exemplary method further comprises the step of inserting a medical grade screw through the femur of a subject in need thereof, through a third bore in the trochanteric fracture nail, and through the opposite side of the subject's femur. In certain embodiments, the medical grade screw may provide additional support to the proximal femoral fracture during healing.
In embodiments wherein a guide is engaged to the superior end of the trochanteric fracture nail during the exemplary method, at the completion of step S408, the guide can be disengaged from the superior end of the nail after the lag screw and laterally inserted screw are advanced.
Although preferred embodiments of the invention have been described using specific terms, such description is for illustrative purposes only, and it is to be understood that changes and variations may be made without departing from the spirit or scope of the following claims.
The entire contents of all patents, published patent applications, and other references cited herein are hereby expressly incorporated herein in their entireties by reference.
This application claims the benefit of priority under 35 U.S.C. § 119(e) of U.S. Provisional Patent Application Ser. Nos. 62/706,448, filed Aug. 18, 2020, and 63/079,011, filed Sep. 16, 2020. The entire content of each of these applications is hereby incorporated by reference herein.
| Number | Date | Country | |
|---|---|---|---|
| 62706448 | US | ||
| 63079011 | Sep 2020 | US |
