EXPANDABLE OSSEOINTEGRATION BONE FIXATION APPARATUS FOR USE IN A VARIETY OF SETTINGS

Abstract

A cortical shaft bone fixation apparatus includes a housing having a leading portion and a trailing portion, the leading portion configured to fit within a diameter of an affected cortical shaft bone, the leading portion having first and second sections. The apparatus further includes an expansion mechanism adapted to transition the first and second sections from a first position to a second position, the first and second sections providing an outward force against the inside surface of the cortical shaft bone when the first and second sections transition from the first position to the second position, the trailing portion of the housing abutting a leading end of the affected cortical shaft bone. The trailing portion of the housing includes a pair of angled tapers extending inwardly toward each other to a minimum separation distance at an extreme end of the housing.

Claims

1. A cortical shaft bone fixation apparatus with a porous surface for use in a variety of settings to promote osseointegration, comprising: an elongated housing configured to partially fit within a diameter of an affected cortical shaft bone and having first and second sides which move in a manner to provide an outward force to the inside surface of the cortical shaft bone when said first and second sides incrementally transition from a first position to a second position; and an insert further including a bolt along a centerline axis of the insert to provide for each first and second sides to move and increase compression within the diameter of the affected cortical shaft bone; the elongated housing further comprising a portion adapted to abut a leading end of the affected cortical shaft bone and provide a force thereon independent of said bolt; the apparatus further comprising a connection member for connection to additional surgical components, the connection member comprising a pair of angled tapers extending inwardly toward each other to a minimum separation distance at an extreme end of said elongated housing.

Description

SUMMARY OF THE INVENTION

[0007] Embodiments described herein include an expandable osseointegration bone fixation apparatus 100 for use in a variety of settings including orthopedic, craniomaxillofacial and veterinary applications. The apparatus 100 is configured to be affixed to a segment of bone B and allow osseointegration with the affected bone segment. The apparatus is designed to be compressed against both the inside I and the leading edge LE of an affected bone. The apparatus 100 includes a housing 102 containing an insert 104 further comprised of two diametrically opposed congruent sections 106, 108. An expansion bolt 110 at the centerline axis CL produces a sliding motion between the two sections 106, 108 and leads to incremental transition between a first contracted and a second expanded position. The housing 102 includes a first side 112 opposite a second side 114 whose diameters when added together are proportionate to the diameter of the affected bone B. The housing 102 is composed of a metallic material and designed to contain the insert 104 having the two diametrically opposed congruent sections 106, 108 at a trailing end 116 and a set of angled tapers 118 at the leading end 120. The apparatus 102 is compressed against the affected bone B by twisting the expansion bolt 110 causing horizontal expansion of the housing 102 while simultaneously advancing the tapers 118 further into the affected bone. Once inserted, a plurality of microscopic pores along the leading end 120 of the housing 102 and along the outer aspect of the tapers 118 enable osseointegration between the bone B and the several metallic surfaces of the apparatus 100.

[0008] In an alternative embodiment, the apparatus 200, 300 includes a plurality of grooves 222, 322 along the exterior walls of the housing portion 202, 302 outside the bone B which enables incremental tightening of a threaded collar 224, 324, causing compression between the collar and the leading edge LE of the bone, in addition to the interior I of the bone.

[0009] In a further alternative embodiment, the apparatus includes a collar with a porous surface to slide toward to the affected bone without rotation. An adjustable nut is then applied opposite the sliding collar. When this nut is tightened, it causes increased pressure between the collar and bone, in addition to the pressure between the outside surface of the tapers and the affected bone.

[0010] In a further alternative embodiment intended for use near the ends of bones, the apparatus includes a transverse bolt designed to cause expansion of the inserts in a direction perpendicular to longitudinal axis of the bone and a plurality of screws inserted at the leading end of the insert to increase coronal compression of the apparatus against the leading edge of the bone.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] A more complete understanding of the present invention, and the attendant advantages and features thereof, will be more readily understood by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein:

[0012] FIG. 1A is a perspective view of an expandable osseointegration bone fixation apparatus, with a tapered conical portion comprising the portion of the housing outside the bone, used to removably attach the apparatus to other metallic components;

[0013] FIG. 1B is a view of the apparatus sliding between the contracted and expanded positions;

[0014] FIG. 2A is an alternate view of the apparatus in an expanded position and further including a threaded collar for additional compression at the end of the bone;

[0015] FIG. 2B is the alternate view of apparatus with the threaded collar now compressed against the bone;

[0016] FIG. 3A is a further alternate embodiment of the apparatus with a threaded nut to be used to compress a collar against bone;

[0017] FIG. 3B is a further alternate embodiment now with threaded nut turned to compress collar against bone;

[0018] FIG. 4 is a further alternate embodiment of the apparatus intended for use near the end of a bone (metaphysis), demonstrating initial preparation of bone with router and guide;

[0019] FIG. 5A is the alternate embodiment of the apparatus inserted into the bone, fixed with screws into the bone, internal transverse bolt placed using removable jig; and

[0020] FIG. 5B is the alternate view of the apparatus now with the transverse bolt tightened, causing expansion of the device within the bone.