GB2138300A

GB2138300A - External orthopedic fixing apparatus

Info

Publication number: GB2138300A
Application number: GB08402778A
Authority: GB
Inventors: Raul N Macle
Original assignee: CUBANA EXPORT IMPORT
Current assignee: CUBANA EXPORT IMPORT
Priority date: 1983-02-02
Filing date: 1984-02-02
Publication date: 1984-10-24
Also published as: DE3345276C2; JPS6122972B2; FR2551345B1; DD218274A5; DE3345276A1; FR2551345A1; JPS59155246A; SU1651779A3; CU21459A1; MX159639A; GB2138300B; GB8402778D0

Abstract

External orthopedic fixing apparatus comprises a pair of hexagonal collars (1, 2) connected parallel to each other by means of a pair of adjustable spacers (3) each extending normal to the planes of the collars and connected to opposite sides of each collar; each collar being further provided (in the sides thereof not connected to the adjustable spacing members) with apertures (4) extending transversely of the collar for mounting fixing rods (8) extending between opposite faces of the collar. In one embodiment (as illustrated) the adjustable spacing members take the form of a male member (9) slideable in a longitudinal aperture in a female member (8) each demountably connected, via screw thread rods (6) and nuts (7), to the collars. In another embodiment, the adjustable spacing means take the form of rotatable screw threaded rods connected to one collar and passing through a thread hole in the other collar. <IMAGE>

Description

SPECIFICATION External orthopedic fixing apparatus This invention is concerned with improvements in and relating to external orthopedic fixing apparatus (hereinafter simply referred to "fixing apparatus") for use in the treatment of various pathological conditions, for example shaft fracture, pseudo arthrosis or the lengthening or shortening of stumps.

According to the invention there is provided fixing apparatus comprising a pair of hexagonal collars connected parallel to each other by a pair of adjustable spacing members each extending normal to the planes of the collars and connected to opposite sides of each collar so that the distance between the collars may be varied; each collar being further provided (in the sides not connected to the adjustable spacing members) with apertures extending transversely of the collarfor mounting fixing rods extending between opposite faces of the collar.

The adjustable members are, in accordance with one embodiment of the invention, demountably connected to the collars, for example by means of screw-threaded rods extending from the adjustable spacing members and passing through holes in the collars and being secured by means of screw nuts or the like.

In accordance with another embodiment of the invention, each adjustable spacing member takes the form of a pair of members comprising a male member connected to one collar and slidable in a longitudinal aperture in a female member connected to the other collar and provided with screw thread means to adjust the relative position of the male and female members one to the other.

In a further embodiment of the invention, particularly intended as fixing apparatus for fingers, each adjustable spacing member takes the form of a rotatable screw threaded rod connected to one collar and passing through a threaded hole in the other collar, the rod being provided with means to rotate it to adjust the spacing between the collars.

The apparatus in accordance with the first embodiment of the invention may be used in the treatment of various conditions and requires relatively short time for mounting in place. Further, this apparatus is generally easy to place or mount since it can be placed already assembled. Finally, it is easy and safe for the patient, or his relatives, to handle the fixer and may be provided with a graduated scale allowing for ready correct operation of the apparatus.

In order that the invention may be well understood reference will now be made to the accompanying drawings in which Figure 1 is an isometric view of one embodiment of fixing apparatus in accordance with the invention; Figure 2 is a side view of an adjustable spacing member used in the apparatus of Figure 1; Figure 3 is a front view of the said adjustable spacing member; Figure 4 is a side view of a collar used in the apparatus of Figure 1; Figure 5 is a plan view of the said collar; and Figure 6 is an isometric view of apparatus in accordance with the invention for use as in the external fixing of fingers.

As shown in Figures 1 - 5, fixing apparatus in accordance with the invention comprises a pair of hexagonal collars, an upper collar 2 and a lower collar 1, joined by two slidable spacing members 3; each collar having elongate slits 4 (for example 5 cms long by 0.3 cm high) in the faces of the collar to which the sliders 3 are not attached. The sliders 3 are demontably attached to the collars by means of two guide rods 5 fixed to the collars and penetrating into corresponding orifices in each end of the sliders.

Between the guide rods 5 there is a hole in the collar through which passes a screw threaded rod 6 extending from each end of the slider and having a nut 7 to make it possible to close the collar to the sliders orto separate them.

Each slider comprises a male member 9 and a female member 10, the male member sliding in a dovetail slit in the female member. An extending portion 11 extends from the base of female member 10 and a bracket 12 extends from the lower part of male member 9. A screw threaded rod extends upwardly from portion 11 and is provided with a nut 14 which engages with bracket 12 so that on turning nut 14 clockwise male member 9 is closed down wardlywith respecttofemale member 10, thereby bringing the collars closer together. Turning the nut in the opposite direct serves to move the male and female members in the opposite relative direction and thus separate the collars.The female member 10 is provided with a graduated scale, for example up to 11 cms long, representing the greatest degree of opening of the adjustable member formed by the male and female members. The pair of slits 4 in opposite faces of collars 1 and 2 are at different heights, for example 3.5 mm different in height, so that when threaded rods 8 are passed through the slits, they do not touch, that is they can go through the bone without touching and provide for good fixing to the bone. The preferred dimensions to the slits (5 cms long by 0.3 cm wide) also offers support and guidance for the rods 8 passing through them, allowing for difference angles at which the bone is faced. Further the slits allow for displacement of the bone, once it is fixed by the rods, when being threaded, and penetrating the bone at low revolutions, behave as a threaded male that provides for solid fixing.The rods normally go through each hexagon at the angle determined by the injury (in the case of displaced fractures), or in the case of lengthening or pseudo arthrosis are not displaced making it possible to correctly tauten the rods 8 with small nuts which pass through the slits 4 thus ensuring immovability of the rods. Lateral displacement of the bone may be corrected by loosening one of the rod ends whilst tightening the other, pulling the bone towards that side, as a result it is possible to correct displacements in four directions, in each collar, with a wide displacement area for each slit.

A total of up to six rods may be employed.

Due to the fact that it may be desired to treat patients with unstable fractures or with a third fragment or it may be required to lower a corticoto mia to relieve a pseudo arthorsis with bone loss, the apparatus may also be provided with means for mounting obliquely extending fixing rods, extending between opposite vertices of the upper and lower collars. These rods also may be tightened with nuts or by means of a bayonet. As will be appreciated, in order to adjust the spacing between the collars it is necessary to remove such obliquely positioned rods.

In the case of a patient with shortening, the fixing apparatus will be placed closed and assembled. That is, the collars will be completely joined to the sliders 3 and these also will be closed. The patient will then be able to handle the apparatus by turning the nut, for example a quarter turn every six hours. If desired the nut may be provided with slits or other marking in its outer phase in order to avoid errors and permit of exact control of the lengthening.

Inthe case of pseudo arthrosis,the apparatus is placed open, according to the surgeon's directions concerning the required compression to produce the bony callous.

In the case of a recent fracture with overriding, th device is placed closed and the overriding is calculated, for example by X-ray examination and both sliders are operated at the same time, for example 0.5 cms over the overriding, and then, using the fixing rods as described above, lateral displacement may be corrected, and once each bony end is placed at the front, the sliders 3 may be closed, until the desired compression is obtained, allowing the patientto become ambulatory within a day.

The fixing apparatus shown in Figures 1 - 5 may be used in the treatment of the following conditions; pseudo arthrosis (femur, tibia, humerus); lengthening (epiphysis - distraction, corticomiaj and fractures (femur, tibia, forearm). Results obtained with the apparatus have been 70% in the treatment of pseudo arthrosis without open surgery and 100% for lengthening and fractures.

The fixing apparatus shown in Figure 6 of the drawings comprises a pair of hexagonal collars 16 and 17 connected by means of rotatable threaded rods 22 each mounted in members 21 connected to lower collar 16 and passing through threaded apertures in upper collar 17 to be turned by nuts 23 to adjust the spacing between the collars. In a similar manner to the apparatus described in connection with Figures 1 - 5, bone fixing rods may extend across the planes of the collars and, similarly, oblique rods may extend between diagonally opposite vertices of the upper and lower collars.

This external fixing apparatus has been used in the lengthening of stumps, in the treatment of open or closed fractures of the phalanxes and in the treatment of congenital abnormalies of the fingers.

It has been found that the apparatus of the invention provides economy in use in that it may minimise hospital stay and the use of medicaments, plaster, bandages or reduce the use of osteosynthesis in such as fractures and pseudo arthrosis.

Finally it is believed to hasten the patient's recovery.

Claims

1. External orthopedic fixing apparatus comprising a pair of hexagonal collars connected parallel to each other by a pair of adjustable spacing members each extending generally normal to the planes of the collars and connected to opposite sides of each collar so that the distance between the collars may be varied; each collar being further provided in the sides not connected to the adjustable spacing members with apertures extending transversely of the collars for mounting fixing rods extending between opposite faces of the collars.

2. Apparatus as claimed in claim 1 in which the collars are demountably attached to the adjustable spacing members by means of threaded rods extending from the ends of the spacing members, passing through holes in the collars and securable thereto bythreaded nuts.

3. Fixing apparatus as claimed 1 or claim 2 in which the apertures in the collars for mounting bone fixing rods take the form of slits to afford displacement of the bone after fixing with bone fixing rods.

4. Apparatus as claimed in any one of the preceding claims in which each adjustable spacing member takes the form of a pair of members comprising a male member connected to one collar and slidable in a longitudinal aperture in a female member connected to the other collar and relatively movable by the action of a screw and threaded rod arrangement.

5. Apparatus as claimed in claim 4 in which the female member is provided with a graduated scale to indicate the relative position of the male member.

6. Apparatus as claimed in any one of the preceding claims in which the collars are also provided with apertures for mounting rods extending obliquely between opposite vertices of the two collars.

7. Apparatus as claimed in clim 1 in which the adjustable spacing member take the form of rotatable threaded rods connected to one collar and passing through threaded holes in the other collar and provided with means for rotating the threaded rods.

8. Apparatus as claimed in claim 1 sunstantially as hereinbefore described with reference to Figures 1 - 5 of the accompanying drawings.

9. Apparatus as claimed in claim 1 substantially as hereinbefore described with reference to Figure 6 of the accompanying drawings.