FR2783699A1 - Intra osseal connector for bone fracture - Google Patents

Abstract

The intra osseal connector for a bone fracture has a central rod (13) onto which two identical sleeves clip at its ends. The ends of the rod can be slotted to allow compression of the ends for fitting of the sleeves. The slots can be opened by screws to expand the ends of the rod.

Description

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LINKING DEVICE

INTRA BONE

  The present invention relates to a connecting device for reuniting two fragments of bone dissociated by fracture or surgical intervention or even to join two bones for a very specific purpose, ie to merge them into this

  which orthopedic surgeons call an "arthrodesis".

  When a fracture occurs for example, the different surgical treatments consist in bringing the two ends of the bone fragments together

  and to bring them together by different means, the most common of which is the use

  tion of screws which are often placed transversely to what

  this is called the "fracture line".

  The criticism that is generally made of this technique is not always to be very reliable or to annoy the patient if the head of the screw has not been very well buried in the bone, or even poorly ensuring an intimate connection between the two bone fragments. One of the "sine qua non" conditions for good calcification of two bones together is very close contact between them with, if possible, a certain compression which has the effect of optimizing the chances of good recovery and d '' thus avoid one of the obsessions of surgeons, ie "pseudarthrosis" which gives a

  fibrous tissue instead of a good bone weld.

  The present invention seeks to overcome these drawbacks by proposing a device which is a kind of screw placed inside the bone and which, after it has been locked, reunites and keeps the two bones or bone fragments compressed. It can be made of metal, resorbable polymers or not and all

biocompatible materials.

  To this end, the invention relates to a device in three elements, two of which

  have a screw appearance and the third is a connecting piece.

  Advantageously, the configuration of the parts is such that they will ideally fit into each other in a harmonious and very contiguous manner in order to ensure the best possible connection

between the two bones.

  According to different variants, the assembly can be made of absorbable material, it being understood that the central part can already be part

  integral with either end piece.

  The present invention and its advantages will appear better in the

  following description with example of embodiment, with reference to the drawings

  annexes. Figures IA, IB, IC represent the

  three separate parts of the invention.

  Figure 2 shows the assembly of

  the connecting piece with the first body of "truncated screw".

  Figure 3 shows the establishment of the second body of "truncated screw" thus achieving the final assembly of the

device according to the invention.

  Figure 4 represents "in situ", it is

  say in the bone, the device uniting the two bone fragments.

  Referring to these figures, the device according to the invention consists of a central part (Figure 1A) and two parts (Figures lB and IC). These three pieces will constitute a set or

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  device secured after "clipping" of the two end pieces (Figures

  IB and IC) on the central part (Figure IA).

  With reference to the invention, the central part (Figure IA) consists of a central body (13) equipped at each of its ends with an element (14). This element (14) is formed of a cylindrical part (6) extended by a part (7) and a cone (8). An axial slot (9) is provided

  in this element (14) and partially extended in the central body (13).

  Said slot (9) reduces the size of the element (14) by compression to introduce said element (14) into the body (15) as

explained below.

  Still with reference to the invention, the so-called end pieces (FIGS. 1B and 1C) are strictly similar. Taken as a whole (15), they are characterized externally by, on their outer periphery, a thread (2) adapted to the internal structure, that is to say spongy of this part of the bone. One end is terminated by an opening (3) opening outwards. This opening (3) that nothing characterizes since of a constant diameter in this part, will further tighten

  in (4) to widen again in (5).

  The other end of these parts (15) in (Figure 1B and Figure IC) also ends in a through hole (1). But, this hole (1) is differentiated by the fact that its interior is, not circular, but faceted to accommodate the end of a hexagon screwdriver for example which will allow the placement in each of the fragments of of both

  so-called end pieces (15) (Figures 1B and IC).

By way of explanation, we can see in

  example (Figure 2) the description of the start of assembly of the entire

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  device. We can see the central part (13) on which one of the two (15) end pieces has been slipped, the end part of which, by its parts 7 and 8, is housed and above all is blocked in the opening 1. This thanks to the axial slot (9) of the central part (13) which, at the time of the passage of the part 4, made it possible to reduce the diameter of the terminal part 7 and 8 of the central part 13. Once this part terminal 7 and 8 reached in opening 1, it expands because the compressed axial slot (9) resumes its initial shape and allows the blocking of part 8 and especially of part 7 which is then retained by the end of the opening 6 whose diameter is

  lower than that of part 7 returned to its original diameter.

  Thus, instantly, the blocking of the intra-bone connection device is carried out, itself supporting the bone fragments which are then found in close contact and very contiguous, thus ensuring the best conditions for good and faster

bone consolidation.

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Claims (4)

  1) Intra-bone connection device characterized in that it consists of a central piece (13) on which two identical pieces (15) are clipped to the two ends of said central piece (13), the device thus formed allowing to join two bone fragments, this device being made of various materials: metal, polymers, absorbable products. 2) Device according to claim 1 characterized in that the part (13) comprises a central body split at the two ends (9) allowing   parts (7) and (8) to be compressed.   3) Device according to claim I characterized in that the two end pieces (15) have on the outer periphery a thread (2), internally these two parts are characterized by an opening (3) opening tightening in (4) to widen in (5) and end in (1) by another through opening provided with facets allowing screwing with an appropriate screwdriver, the parts (4) and (5) will momentarily compress the parts (8) and (7) of the central part (13) before allowing their expansion again in (3)   thus ensuring the clipping of the parts (15) on the central part (13).   4) Device according to claim 1, but may comprise only two parts; the first monoblock having incorporated one of the two end pieces (15) and the central piece (13) while the other piece (15)   will be clipped onto the visible part of the central element.