FR2838626A1

FR2838626A1 - Sawing jig for femur condyle parts comprises miter box with parallel orifices for receiving positioning pins previously implanted in femur

Info

Publication number: FR2838626A1
Application number: FR0204947A
Authority: FR
Original assignee: CABINET BOETTCHER
Current assignee: CABINET BOETTCHER
Priority date: 2002-04-19
Filing date: 2002-04-19
Publication date: 2003-10-24
Anticipated expiration: 2022-04-19
Also published as: FR2838626B1

Abstract

The sawing jig for condyle parts (2,3) of a femur (1) for implanting a knee prosthesis comprises a miter box (6) which to be fitted in the end of the femur. It has two parallel holes(13,14) able to receive two positioning pins (4,5) previously implanted in the femur condyles. An Independent claim is included for ancillary equipment for placing the saw jig.

Description

support (1).support (1).

La presente invention concerne le domaine de la chirurgie orthopedique, notamment la pose d'une prothese The present invention relates to the field of orthopedic surgery, in particular the fitting of a prosthesis

de genou.knee.

Une prothese de genou comporte une piece femorale et une piece tibiale avec, interposee entre elles, un in- sert fixe ou mobile par rapport a la piece tibiale. La pose de ces composants requiert de proceder a la decoupe A knee prosthesis comprises a femoral piece and a tibial piece with, interposed between them, a fixed insert or movable relative to the tibial piece. Installing these components requires cutting

des parties condyliennes du femur et celle du plateau ti- condylar parts of the femur and that of the plateau ti-

bial. La decoupe du femur consiste a realiser cinq faces bial. Cutting the femur consists of making five faces

sur les condyles qui correspondent aux cinq faces du pro- on the condyles which correspond to the five sides of the pro-

fil concave polygonal de la piece de prothese femorale. Concave polygonal wire of the femoral prosthesis piece.

Ces cinq faces comprennent une face distale qui est per- These five sides include a distal side which is per-

pendiculaire a l'axe mecanique de la jambe, c'est a dire a la droite passant par l' articulation de la hanche et celle de la cheville, la jambe etant en extension. Wiles comprennent egalement deux chanfreins de liaison de cette pendulum to the mechanical axis of the leg, ie to the right passing through the hip joint and that of the ankle, the leg being in extension. Wiles also include two connecting chamfers of this

face distale a une face anterieure et une face poste- distal side has an anterior side and a post-side

rieure. La precision de la geometric de ces decoupes est importante: elle conditionne l' adaptation de la prothese pool. The precision of the geometric of these cuts is important: it conditions the adaptation of the prosthesis

a la morphologic naturelle du patient done le bon fonc- to the patient's natural morphology therefore the good function

tionnement de ['articulation artificielle. operation of the artificial joint.

Les differents plans de coupe doivent etre deter- The different cutting plans must be determined

mines en fonction de la morphologic de l' articulation na- mines according to the morphology of the natural joint

turelle et de sa pathologic de maniere a restaurer un fonctionnement mecanique correct de ['articulation. A cet turelle and its pathology so as to restore correct mechanical functioning of the joint. In this

effet on utilise des guides de coupe que l' on fixe tempo- effect we use cutting guides that we fix temporarily

rairement a ltos et c'est a l' occasion de leur mise en place qu'il faut deployer le plus grand vein. Selon une pratique repandue, on procede a la mise en place precise d'un premier guide pour realiser une premiere face qui, usually at ltos and it is when they are put in place that the largest vein must be deployed. According to a widespread practice, we proceed to the precise installation of a first guide to achieve a first face which,

apres retrait de ce guide, constituera une face de refe- after removal of this guide, will constitute a refe-

rence pour la mise en place d'un ou d'autres guides pour les autres decoupes. L'utilisation de plusieurs guides successifs introduit necessairement des imprecisions dans la geometric obtenue. En outre, il s'agit d'une pratique Reference for the installation of one or other guides for other cuts. The use of several successive guides necessarily introduces inaccuracies in the geometric obtained. In addition, it is a practice

relativement longue, complexe et malcommode. relatively long, complex and awkward.

I1 existe done un besoin de simplifier la proce cure chirurgicale tout en apportant une amelioration dans There is therefore a need to simplify the surgical procedure while bringing an improvement in

la performance de celle-ci.the performance thereof.

A cet effet, l' invention a pour premier objet un gabarit de coupe des parties condyliennes d'un femur en vue de ['implantation de la piece femorale d'une prothese To this end, the first object of the invention is a template for cutting the condylar parts of a femur for the purpose of implanting the femoral part of a prosthesis.

de genou, qui comporte une bolte a onglets propre a em- knee, which has a clean miter bowl to hold

bolter l'extremite du femur a resequer pourvue de deux bolt the end of the femur to be resected provided with two

orifices paralleles apses a recevoir deux broches de po- parallel holes able to receive two pins of po-

sitionnement, prealablement implantees dans les parties location, previously implanted in the parts

condyliennes du femur.femur condylar.

I5 Grace a ces deux orifices la precision de la re section ne depend plus que de la precision de l' implantation des deux broches dans le femur. Cette pre cision peut etre obtenue de plusieurs manieres differen tes. On peut utiliser un appareil ancillaire dont un mode de realisation sera decrit ci-apres. I1 est egalement possible d'implanter les deux broches en question au moyen d'un systeme dit << de navigation >> qui fait appel a des moyens electroniques de reperage du plan des broches dans un repere tridimensionnel dans lequel la forme et la disposition du membre du patient est reconnue au moyen de I5 Thanks to these two orifices the precision of the re - section only depends on the precision of the implantation of the two pins in the femur. This precision can be obtained in several different ways. An ancillary device can be used, an embodiment of which will be described below. It is also possible to locate the two spindles in question by means of a so-called "navigation" system which uses electronic means for locating the plane of the spindles in a three-dimensional reference in which the shape and arrangement of the member of the patient is recognized by

capteurs de position et qui, par des moyens informati- position sensors and which, by computerized means

ques, calcule et determine le plan des broches ainsi que ques, calculates and determines the plan of the pins as well as

leur position dans ce repere, en fonction de donnees en- their position in this benchmark, according to data in-

trees par le chirurgien qui traduisent la position et les dimensions de la prothese qu'il a choisie d'implanter trees by the surgeon who translate the position and dimensions of the prosthesis he has chosen to implant

apres ltexamen clinique du patient.after clinical examination of the patient.

La position de ces broches est en general dans un plan qui est secant de l'un au moins des plans de coupe a The position of these pins is generally in a plane which is intersecting at least one of the cutting planes with

realiser. Le gabarit de l' invention comporte une plurali- achieve. The template of the invention comprises a plurali-

te d' orifices lateraux secondaires formant des guides de mise en place de broches secondaires qui permettent d' en realiser la fixation sur l'os a l'exterieur des plans de coupe a realiser. Ces broches etant mises en place, il est alors te of secondary lateral orifices forming guides for placing secondary pins which make it possible to fix it to the bone outside the cutting planes to be produced. These pins being in place, it is then

possible de retirer les broches primaires et degager ain- possible to remove primary pins and clear

si les plans de coupe.if the cutting plans.

Le materiel ancillaire pour mettre en place les broches primaires susdites comporte, selon la presente invention, - une tige centromedullaire, - un canon de compensation du valqus femoral glisse sur la tige centromedullaire, - un calibre comprenant une premiere potence avec un montant pourvu d'une lumiere de coulissement sur le canon de compensation et une traverse a une ou deux bran ches pour s'appuyer sur la partie posterieure des con dyles et comprenant une deuxieme potence dont le montant est monte coulissant par rapport au montant de la pre miere potence et dont la traverse, parallele au montant de la potence, est equipee en extremite d'un palpeur de la corticale anterieure du femur, un palonnier monte pivotant sur le calibre au tour dun axe perpendiculaire au plan des montants des potences et situe en dessous du canon de compensation, ce palonnier comportant des guides de percage paralleles si tues de part et d'autre de l'axe de pivotement du palon nier et au-dessus de celui-ci, - et au moins une tige rapportee de maniere amo vible de chaque cote du palonnier dans un plan parallele The ancillary material for positioning the aforementioned primary pins comprises, according to the present invention, - a centromedullary rod, - a barrel for compensating the femoral valqus slides on the centromedullary rod, - a caliber comprising a first stem with an amount provided with a sliding light on the compensating barrel and a crosspiece with one or two branches to rest on the rear part of the rods and comprising a second stem, the amount of which is mounted to slide relative to the amount of the first stem and whose crosspiece, parallel to the amount of the stem, is equipped at the end with a feeler of the anterior cortex of the femur, a spreader rises pivotally on the gauge around an axis perpendicular to the plane of the amounts of the stem and located below the barrel compensation, this spreader comprising parallel drilling guides if killed on either side of the pivot axis of the nier hoist and above it, - And at least one rod removably attached on each side of the lifter in a parallel plane

a celui contenant les axes des guides de percage. to the one containing the axes of the drilling guides.

D'autres caracteristiques et avantages ressorti Other features and advantages stood out

ront de la description donnee ci-apres a titre indicatif from the description given below for information only

d'un mode de realisation du gabarit selon l' invention et an embodiment of the template according to the invention and

de l'appareillage ancillaire permettant sa mise en place. ancillary equipment allowing its installation.

Il sera fait reference aux dessins annexes parmi lesquels: - la figure 1 est une vue exterieure diun gabarit de coupe et de l'extremite du femur equipee de broches pour l'accueillir, - la figure 2 illustre la fixation du gabarit sur le femur avant la coupe, - la figure 3 est une vue exterieure de l'appareillage ancillaire pour ['implantation des broches Reference will be made to the accompanying drawings, in which: - Figure 1 is an external view of a cutting template and of the end of the femur fitted with pins to accommodate it, - Figure 2 illustrates the fixing of the template to the front femur the section, - Figure 3 is an external view of the ancillary equipment for ['implantation of the pins

sur les condyles de femur.on femur condyles.

L'extremite du femur 1 represente a la figure 1 The end of femur 1 is shown in Figure 1

presente deux parties condyliennes 2 et 3 dont les surfa- has two condylar parts 2 and 3, the surfaces of which

ces distales, tournees vers l' avant, comportent deux bro- these distals, facing forward, have two pins

ches 4 et 5, implantees dans ces surfaces distales au ches 4 and 5, implanted in these distal surfaces at

moyen d'une procedure qui permet leur implantation pre- by means of a procedure which allows their pre-implantation

cise en position et en orientation dans l'os femoral. cise in position and orientation in the femoral bone.

L'une de ces procedures sera decrite ci-apres en regard de la figure 3 qui represente un appareil ancillaire de One of these procedures will be described below with reference to FIG. 3 which represents an ancillary apparatus of

mise en place de ces broches.placement of these pins.

Le gabarit de coupe selon ['invention se presente sous la forme d'une bolte a onglets 6 qui comporte une paroi principale 7 dont l'epaisseur est suffisante pour que des fentes traversantes telles que 8, 9, 10, 11 et 12 puissent chacune constituer un guide plan pour une lame The cutting template according to the invention is in the form of a miter bolt 6 which has a main wall 7 whose thickness is sufficient so that through slots such as 8, 9, 10, 11 and 12 can each constitute a plan guide for a blade

de coupe y etant introduite. En outre, cette paroi prin- cutting being introduced. In addition, this main wall

cipale presente deux orifices 13 et 14 qui vent destines a accueillir les broches 4 et 5 quand on approche la bolte 6 des condyles 2 et 3. On comprend que lorsque la cipale presents two orifices 13 and 14 which wind intended to accommodate pins 4 and 5 when we approach the bolte 6 of condyles 2 and 3. We understand that when the

bolte 6 vient en appui contre la surface distale des con- bolte 6 abuts against the distal surface of the

dyles ou de l'un d'eux, le moins use, par sa surface non visible sur la figure, les plans des fentes 8 a 12 vent dans une position parfaitement determinee par rapport a ces condyles, position qui correspond aux differents plans de coupe (en general 5)a realiser pour mettre en place la partie femorale d'une prothese totale de genou. De chaque c8te de la paroi principale 7, la bolte 6 comporte des pastes laterales 15 et 16 qui encadrent lateralement les condyles lorsque la bolte est en appui sur l'os. Ces pastes 15 et 16 vent egalement pourvues d'orifices (deux par paste) tels que 17 et 18 qui vont dyles or one of them, the least used, by its surface not visible in the figure, the planes of the slots 8 to 12 wind in a perfectly determined position with respect to these condyles, position which corresponds to the different cutting planes (in general 5) to perform to set up the femoral part of a total knee prosthesis. On each side of the main wall 7, the bolte 6 has lateral pastes 15 and 16 which laterally frame the condyles when the bolte is in contact with the bone. These pastes 15 and 16 are also provided with orifices (two per paste) such as 17 and 18 which go

servir de guides pour la mise en place de broches secon- serve as guides for the installation of secondary pins

daires de fixation de la bolte 6 sur le femur, comme il- bolts 6 fixing bolt on the femur, as it-

lustre par la figure 2. Ces broches secondaires 19, 20, 21 et 22 mises en place comme sur la figure 2, permettent de retirer les broches 4 et 5 pour liberer les plans de chandelier in FIG. 2. These secondary pins 19, 20, 21 and 22 put in place as in FIG. 2, allow pins 4 and 5 to be removed in order to free up the planes of

coupe traverses par les broches principales 4 et 5. cross-cuts through main pins 4 and 5.

Une lame de scie 23 est representee a la figure 2 A saw blade 23 is shown in Figure 2

introduite dans la fente -guide 9 au cours de la real isa- introduced into the slot -guide 9 during the real isa-

tion du plan de coupe anterieur du femur. On procede ain si a la coupe distale guidee par la fente 8, a la coupe posterieure guidee par la fente 12 et aux deux coupes tion of the femur's previous cutting plane. This is done if the distal cut guided by the slot 8, the posterior cut guided by the slot 12 and the two cuts

chanfrein guidees par les fentes 10 et 11. chamfer guided by slots 10 and 11.

L'appareillage represente a la figure 3 sert a mettre en place les broches 4 et 5. Cet appareillage est compose d'une tige centromedullaire 24 que le chirurgien met en place, de maniere connue, dans le femur a partir de la gorge trochleenne. Cette tige definit ou suit l'axe anatomique du femur. Wile recoit a coulissement un canon de compensation du valqus femoral qui definit a partir de l'axe anatomique, l'axe mecanique du membre (ou du The apparatus represented in FIG. 3 is used to position pins 4 and 5. This apparatus consists of a centromedullary rod 24 which the surgeon places, in a known manner, in the femur from the trochlear throat. This rod defines or follows the anatomical axis of the femur. Wile receives with sliding a barrel of compensation of the femoral valqus which defines starting from the anatomical axis, the mechanical axis of the member (or

moins une parallele a celui-ci) auquel doivent etre pa- minus a parallel to it) which must be pa-

ralleles les broches 3 et 5 pour que le plan de coupe distal soit, comme recherche, perpendiculaire au plan de align pins 3 and 5 so that the distal cutting plane is, as shown, perpendicular to the plane of

ces broches.these pins.

On a represente sur cette figure un calibre 26 compose de deux pieces 27 et 28 en forme de potences et coulissantes l'une par rapport a l'autre le long de leur montant. Ainsi, la piece 27 comporte un montant 27a et une traverse inferieure 27b. Le montant 27a est pourvu d'une lumiere centrale oblongue 29 dans laquelle le canon peut coulisser. Des rainures laterales vent prevues a cet effet sur la surface du canon pour recevoir les bords de la lumiere 29. La traverse inferieure 27b est en forme de palette qui vient prendre appui sur la surface poste rieure des condyles 2 et 3 du femur. La piece 28 possede egalement un montant 28a, creux qui peut coulisser sur le montant 27a et qui comprend une lumiere oblongue 30 qui decouvre la lumiere 29 et au travers de laquelle le canon passe librement. En partie superieure, ce montant creux 28a possede une traverse 28_ qui porte a son extre mite libre un palpeur 31 destine a prendre appui sur la corticale anterieure du femur. On notera egalement que le montant 28a possede une fenetre frontale 32 au travers de laquelle une graduation 33 du montant 27a apparalt. Cette fenetre joue avec la graduation le r81e d'un indicateur We have shown in this figure a caliber 26 composed of two pieces 27 and 28 in the form of brackets and sliding relative to each other along their amount. Thus, the part 27 comprises an upright 27a and a lower cross member 27b. The upright 27a is provided with an oblong central lumen 29 in which the barrel can slide. Side wind grooves provided for this purpose on the surface of the barrel to receive the edges of the light 29. The lower cross member 27b is in the form of a pallet which comes to bear on the rear posterior surface of the condyles 2 and 3 of the femur. The piece 28 also has a hollow upright 28a which can slide on the upright 27a and which includes an oblong light 30 which discovers the light 29 and through which the barrel passes freely. In the upper part, this hollow upright 28a has a cross member 28_ which carries at its free end a probe 31 intended to bear on the anterior cortex of the femur. It will also be noted that the upright 28a has a front window 32 through which a graduation 33 of the upright 27a appears. This window plays with the scale the r81e of an indicator

de la taille de la prothese a implanter. the size of the prosthesis to be implanted.

La partie inferieure du montant 28a comporte une embase horizontale 34 avec des ailes laterales 34a, 34_ dont la face non visible sur la figure est destinee a ve nir s'appliquer contre au moins l'un des condyles 2 et 3 du femur. Un moyen de serrage non represente est prevu entre les pieces 27 et 28 du calibre pour le maintenir dans sa position refermee sur le femur, c'est-a-dire la palette 27_ au contact des condyles et le palpeur 31 au The lower part of the upright 28a comprises a horizontal base 34 with lateral wings 34a, 34_ whose face not visible in the figure is intended to come to be applied against at least one of the condyles 2 and 3 of the femur. A clamping means not shown is provided between the pieces 27 and 28 of the caliber to maintain it in its closed position on the femur, that is to say the pallet 27_ in contact with the condyles and the probe 31 at

contact de la corticale anterieure.contact of the anterior cortex.

L'embase 34 est pourvue a son extremite infe The base 34 is provided at its lower end

rieure d'un palonnier 35 tournant autour d'un axe perpen- upper of a spreader 35 rotating around a perpetual axis

diculaire 36 a la face de la piece 28, 34 en appui sur les condyles et situe dans l'axe des montants coulissants du calibre. Ce palonnier est equipe a l'extremite de cha cun de ses bras d'un orifice 37 situe audessus de son axe de pivotement 36, lesquels orifices peuvent ainsi etre deplaces en regard de lumieres traversantes 38 et 39 des ailes 34_, 34b de l'embase. Les orifices 37 servent de support a des guides de percage 40. La position angu faire du palonnier autour de son axe 36 est fixee par tout moyen et notamment par encliquetage au moyen de crans prevus en correspondence sur le palonnier et l'embase. Le palonnier possede enfin des orifices lateraux 41 pour la mise en place de tiges 42 s'etendant dans la direction du palonnier et debordant des ailes de l'embase. On remarquera que les ailes de liembase vent conformees en gradins G. L'appareil decrit ci-dessus est utilise de la ma diculaire 36 on the face of the part 28, 34 resting on the condyles and located in the axis of the sliding uprights of the caliber. This lifter is fitted at the end of each of its arms with an orifice 37 located above its pivot axis 36, which orifices can thus be moved opposite facing lights 38 and 39 of the wings 34_, 34b of the base. The orifices 37 serve as supports for drilling guides 40. The angular position of the lifter around its axis 36 is fixed by any means and in particular by snap-fastening by means of notches provided in correspondence on the lifter and the base. The lifter finally has lateral holes 41 for the establishment of rods 42 extending in the direction of the lifter and projecting from the wings of the base. It will be noted that the wings of the base wind conform to steps G. The apparatus described above is used in the ma

niere suivante. Apres la mise en place de la tige centro- next niere. After placing the central rod

medullaire 24, le chirurgien choisit le canon 25 de com- medullary 24, the surgeon chooses the cannon 25 of

pensation du valqus femoral qui correspond au resultat de thought of the femoral valqus which corresponds to the result of

son examen clinique, parmi une gamme de canons a sa dis- his clinical examination, among a range of cannons at his disposal

position (par exemple quatre canons produisant une angu position (for example four cannons producing an angu

ration de 3, 5, 7 ou 9 degree sur l' axe centromedul- ration of 3, 5, 7 or 9 degree on the centromedul axis

laire). Le chirurgien introduit ensuite le calibre 26 sur ce canon (la lumiere 29 possedant a cet effet une partie elargie a son extremite inferieure qui lui donne une forme en trou de serrure) et place la palette 27b en ap pui sur la surface posterieure des condyles, le palpeur 31 en appui sur la corticale et la face de ce calibre tournee vers le femur en appui sur le condyle le moins use. Il procede ensuite au blocage du calibre. Par la fe lar). The surgeon then introduces the caliber 26 on this barrel (the lumen 29 having for this purpose an enlarged part at its lower end which gives it a keyhole shape) and places the pallet 27b in ap pui on the posterior surface of the condyles, the feeler 31 resting on the cortex and the face of this caliber facing the femur resting on the least used condyle. It then proceeds to block the caliber. By the fe

8 28386268 2838626

netre 32, il lit la taille de la partie femorale de la prothese a mettre en place (dans le cas d'une indication netre 32, it reads the size of the femoral part of the prosthesis to be put in place (in the case of an indication

intermediaire, il procede au choix de la prothese infe- intermediate, he proceeds to the choice of the lower prosthesis

rieure ou superieure). Par une visee frontale, il appre cie au moyen des gradins G. qui portent des reperes, la largeur de la partie femorale de la prothese qu'il entend superior or superior). By a frontal aim, he appreciates by means of the steps G which carry markings, the width of the femoral part of the prosthesis which he hears

poser en fonction de la largeur de l' articulation natu- install according to the width of the natural joint

relle. Afin de regler l' orientation de cette prothese a ltextremite du femur, dans le plan de coupe distal, il agit sur le palonnier 35 autour de l'axe 36 au moyen d'un bouton de manoeuvre 35a. L'ancillaire selon l' invention lui permet d'utiliser au choix l'une des trots references habituelles utilisees pour fixer cette orientation. A l' aide des tiges 42, qui visualisent l' orientation du plan des axes des orifices 37, done des axes des guides de percage 40, il peut se referer aux epicondyles de Relle. In order to adjust the orientation of this prosthesis at the end of the femur, in the distal cutting plane, it acts on the spreader 35 around the axis 36 by means of an operating button 35a. The ancillary device according to the invention allows it to use one of the usual reference trots used to fix this orientation. Using the rods 42, which display the orientation of the plane of the axes of the orifices 37, and therefore of the axes of the drilling guides 40, it can refer to the epicondyles of

l' articulation naturelle en placant ces tiges parallele- the natural articulation by placing these rods parallel-

ment a l'axe frontal qui joint ces epicondyles. Il lui est possible egalement de viser par la fenetre centrale la ligne de Whiteside qu'il aura prealablement marquee sur ['articulation (entre les deux condyles) au bistouri electrique et de placer les tiges 42 perpendiculairement a la vision qu'il a de cette ligne. Il lui est enfin pos sible de placer les tiges 42 parallelement a la ligne de contact de la palette 27b avec les surfaces posterieures ment to the frontal axis which joins these epicondyles. It is also possible for him to aim by the central window the line of Whiteside which he will have previously marked on the articulation (between the two condyles) with the electrosurgical unit and to place the rods 42 perpendicular to the vision which he has of this. line. It is finally possible for him to place the rods 42 parallel to the contact line of the pallet 27b with the posterior surfaces.

des condyles.condyles.

Les guides de percage etant ainsi mis en place, il suffit au chirurgien d'implanter les broches 4 et 5 The drilling guides being thus put in place, it suffices for the surgeon to implant pins 4 and 5

autotaraudante et de fixer la bolte a onglets 6 corres- self-tapping and fix the miter bolt 6 corres-

pondant a la taille de la piece femorale choisie, apres depending on the size of the femoral part chosen, after

avoir retire l'ancillaire.have removed the ancillary.

On notera enfin que, pour certaines gammes de Finally, note that for certain ranges of

9 28386269 2838626

protheses, l'epaisseur distale a retrancher aux condyles est touj ours de huit millimetres. Les boltes a onglets 6 prostheses, the distal thickness to be cut off from the condyles is always eight millimeters. Miter bolts 6

associees a cette gamme vent telles que la coupe des con- associated with this wind range such as cutting

dyles guidee par la fente 7 est touj ours une ablation d'epaisseur egale a ces huit millimetre. Or, certaines articulations demande de proceder a une ablation plus epaisse. Dans ces conditions, afin de pouvoir poser des dyles guided by the slot 7 is always an ablation of thickness equal to these eight millimeters. However, certain joints require a thicker ablation. In these conditions, in order to be able to ask

protheses de la gamme consideree, le calibre 26 peut com- prostheses of the range considered, the 26 caliber can

porter a l'arriere du montant 28a un gabarit de sciage qui stetend audessus de l'os qui se fixe sur la traverse 28_ et qui presente deux fentes de part et d'autre de cette traverse pour guider une lame de scie parallelement a la face arriere du calibre 26 afin de resequer quelques millimetres sur la partie distale du femur de part et d'autre de la tige centromedullaire Le chirurgien ensuite rapproche le calibre de la face fralchement realisee et carry at the back of the upright 28a a sawing template which extends above the bone which is fixed on the crosspiece 28_ and which has two slots on either side of this crosspiece to guide a saw blade parallel to the face back of caliber 26 in order to resect a few millimeters on the distal part of the femur on either side of the centromedullary rod The surgeon then brings the caliber closer to the freshly made face and

procede aux reglages comme precedemment. proceed to the settings as above.

Y 2838626Y 2838626

vv

Claims

RESELL I CAT I ONS

1. Template for cutting the condylar parts (2, 3) of a femur (1) for the purpose of implanting the femoral part of a knee prosthesis, characterized in that it includes a miter bolt (6 ) suitable for embolishing the end of the femur to be resected provided with two parallel through orifices (13, 14) able to receive two pins (4, 5) for positioning previously implanted

in the condylar parts (2, 3) of the femur.

2. Template according to claim 1, characterized in that it comprises a plurality of lateral orifices (17, 18) for the establishment of fixing pin

the bolt (6) on the condylar parts.

3. Template according to any one of the preceding claims, characterized in that it comprises the five cutting guides (8, 9, 10, 11, 12) necessary for the

placement of the femoral part of the prosthesis.

4. Ancillary apparatus for fitting the template

according to one of the preceding claims, characterized in

what it includes: - a centromedullary rod (24), - a barrel (25) for compensating the femoral valqus slides on the centromedullary rod, - a gauge (26) comprising a first stem (27) with an upright (27a) provided with a light (29) sliding on the compensation barrel (25) and a crosspiece (27b) to bear on the rear part of at least one condyle (2, 3) and comprising a second bracket (28) of which the amount (28a) is slidably mounted relative to the amount (27a) of the first bracket (27) and whose crosspiece (28b) is equipped at the end with a feeler (31) of the cortex of the femur (1), { - 1i - a stirrup bar (35) my pivoLanL on the caliber (26) around an axis (36) perpendicular to the plane of my stanDeMeLanLs eLu Below the cannon (25) compenaLion, this rudder comorLanL guides guides perching (37, 40) parallel to each other and from

the pivotal axis (36) of the lifting beam above it

him, eL at least one Lige (42) reported in a way

removable from each lifter cCL in a parallel plane

The one that contains the axes of the drilling guides.

1Q 5. equipment according to claim 4, charac Ldris in that it includes maneuvering means (25a)

of the tacker's pivoLemeL (35) on the caliber (26).

6. Apparatus according to one of the claims 4, characterized in that it comprises a set of several

cannons (25) of copensaLion of the fAmoral valgus.

7. Apparatus according to one of claims 4 6, characterized in that it comprises two guide pins (4, 5) implanted in the bone at the LraverG of the drilling guides. =