GB2583537A

GB2583537A - Trial neck, kit and method

Info

Publication number: GB2583537A
Application number: GB1906320.5A
Authority: GB
Inventors: Kinbrum Amy; Robinson Stephen
Original assignee: DePuy Ireland ULC
Current assignee: DePuy Ireland ULC
Priority date: 2019-05-03
Filing date: 2019-05-03
Publication date: 2020-11-04
Also published as: GB201906320D0

Abstract

A trial prosthetic neck 100 for orthopaedic surgery comprising an elongate neck part 2, a connection feature located at a proximal end 4 of the elongate neck part for connecting the trial neck to a trial head, and a base 106 located at a distal end of the elongate neck part. The base has a distally facing underside 6 in which an opening 8 is provided. A collect 120 is located in the opening for connecting the trial neck to the spigot of a broach (28, Fig 5). The collet preferably comprises a plurality of inclined, resiliently deformable fingers 122 separated by gaps 126. A plurality of apertures (108, 118, Fig 3) may be provided in a side of the trial neck, the openings communicating with the gaps between the fingers such that a fluid may be passed through the openings to allow for cleaning of the trial neck, and specifically the opening and collet thereof. A kit comprising a trial neck and a spigoted broch is also claimed.

Description

TRIALNECK, AND ME invention also invention also

HELD T NVENTION

This inven ion relates to a trial neck for orthopaedic surgery. relates to a kit includinghone'otm oretrial necks for orthopaedic surgery.

retatesto,'a method of performing * aedie surgery. ;BACK ilZ,XTLIND 'FBI-I I _7N' Hip replacement is sa surgical procedure in which the Tip joint is replaced by a prosthetic implant. Total replacement of the hip joint volves installing an acetabular cup implant in the acetahulum of a patient and installing a prosthetic in the femur of the, patient. The prosthetic typically includes a stem, which is received in the medullary canal of the femur, and a head having a bearing surface which is received in the acetabulum or acetabular cup implant. The prosthetic typically also includes a neck which extends between a proximal end of the stem and the head. ;ccessful hij, replacement s e_, requires co positioning and alignment acetabular cup implant he prosthetic itself. Misalignment VTisalignment andlor the selection an inappropriately sized acetabular ip implant andlor the prosthetic may result is restricted movement of the prosthetic an accelerated wear and tear of the hearing surfaces of the acetabular cup implant and the hearing surface of the head. Various factors are involved in achieving this correct positioning and alignment. At least some of these factor relate to the neck of the prosthetic. These factors may include, for instance, the length of the neck, and an angular orientation (offset) of the neck relative to the stem. ;Hip replacement surgeiy= usually involves nialling the various components acetautilar cup implant and the prosthetic. As part of this, various sizes of broach m used to prepare the medullary canal of the femur. Once the broach is inserted in the femur, a trial neck and trial head may also be attached to the broach, in order to evaluate whether a prosthetic having, a neck and head of that type (e.g. in terms of the size and offset of the neck) would appropriate, for the patient. ;After the urgeon 7s sat=:stied that the chosen combination of broach, trial neck and dead are correctly poFsitamed and aligned, they may he MIMS, ed and replaced with the self summAgy OF THEINVENTIQN Aspects of the invention are set out in the accompanying independent and dependent claims. Combinations of features from the dependent claims may be combined with features of the independent claims as appropriate and not merely as explicitly set out in the claims. ;According to an aspect of the invention, there is provided a trial neck for orthopaedic surgery, the trial neck comprising: an elongate neck part extending along a neck axis of the trial neck; a connection feature located, at a proximal end of the elongate neck part for connecting the trial neck to a trial head; a base located at a distal end of the elongate neck park, the base having a distally facing underside; an opening extending into the trial neck from the distally facing underside; and a collet located in the opening for connecting the trial neck to a spigot of a broach. ;The provision of the collet inside the opening can constitute a simple and robust way of connecting the trial neck to the spigot of a breach. ;The opening may extend along an axis. The collet may include a plurality of fingers. ;The fingers may be configured to deflect away from the axis along which the opening extends, on insertion of the spigot into the opening. ;The fingers may he resiliently deflectable away from the axis along which the opening extends. This can allow the fingers to grip the spigot when it is received within the opening. ;The fingers may point distally. Alternatively, the fingers may point proximally The collet may have two fingers. The collet rimy have four fingers. ;The trial neck may have at least one further opening. Each farther opening may extend between the opening in which the collect is located and an outer surface of the trial neck. lire trial neck may include a plurality of the further openings. The further openings) can provide access to the interior of the, opening in which the collet is located for clean opening mid the collet by flushing a fluid through the further opening(s). ;The or each opening extend rod all c=ttttt and with respect t© the axis dich the opening in which the collet is located extends. ;The fircollet gers'of lte co let rrray be separated intervening gaps. At least one further openings may be aligned witfa one of the interveni gaps. This can improve laid flow into (or out ot) the opening la the further opening(s). ;The collet may cornprise-a different material to a remainder of the trial neck. For instance, this can allow the trial neck to be from a rigid, robust material, whereas the collect may be made from a resilient, flexible material. ;he crillet may:prise a polymer. ;The trial neck may comp se a metal. ;Tho collet tnay be heldwithintheiope g by a The coil may by ig formed xnitla the trial neck. ;The trial neck may include an anti rotation feature or preventing rotation of the trial neck elative to a broach when the ik is connected to the broach. ;The anti-rotation may include a protrusion extending distally from the distal underside of the base fbr insertion m an opening in a proximal end of the broach, The orthopaedic surgery may be a hip replacement procedure. However, it is also envisaged that embodiments of this ntion may be applicable to shoulder surgery, According to another aspect invention, there isprovided a kit for Taedic y, the kit comprising the trial neck according to any of claims to 18 and a broach. ;The kit may include a trial neck accorcng of claims 1 to 1 R and a plurality of said broaches, In such embodiments, at least some of the broaches in the kit may be of different sizes to the other broach(es) in the kit. ;The kit may inciuc of saiC trial necks according to any of claims I to 18 and a plurality of said broaches, In such embodiments, at least some of the trial necks and/or aches in the kit may be of different sizes to the. other trial neck(s) and/or broach(es) in the k According tcy a further aspect of the invention, there is provided a method of perfornnngorthopaedic surgery, the method comprising: inserting an elongate stern of a broach into an intramedullary canal of a hone, wherein the broach comprises a spigot extending proximally from a proximal end of the elongate stem for connection to a neck; and connecting atrial neck to the broach, wherein the trial neck, comprises: an elongate neck part extending along a neck axis of the trial neck; a connection feature located at a proximal end of the elongate neck part for connecting the trial neck to a trial head; located at a distal end of the elongate neck pars, tare base having a distally facing underside; an opening extending into the al neck from the distally facing underside; and a eel let located in the opening for connecting the trial neck to said spigot, wherein said connecting the trial neck to the broach comprises inserting the spigot into the 1 he pro collet inside the opening can constitute a simple and robus of connecting theneeic to the spigot of a broach. ;The opening may extend along an a,xis. The collet may inelude a plurality gers. ;The fingers may deflect away from the axis along which the opening extends, can insertion of the spigot into the opening. ;The fingers may deflect resit ends awvay from the axis along Inch the o ening extends, for griping the spigot when itreceived within the opening. ;The trial neck. may include at least one further opening. The at least one further opening may extend between the opening in which the collect is located and an outer surface of the trial neck. The method may further include clearing the trial neck by passing a fluid through the at least one further opening, The fingers of the collet may be separated by intervening gaps. At least one further opening may be aligned with an intervening gap. The method may further include passing the fluid through the at least one further opening and through the intervening gap aligned with the further opening. ;The orthopaedic surgery may be a hip replacement procedure. However. it is also envisaged that embodiments of this invention may be applicable to shoulder surgery. ;BRIEF DESCRIPTION O TI[E>")1k, WINOS ;En bodm e present invention will be described hem nafte by was of example on y, withreference the accompanying drawings in which like relate to like elements and in which: Figure I shows attached to a broach in accordant with an embodiment of this invention; Figure 2 shows a cross section of a broach of the ind shown in Figure l, Figure 3 shows a trial neck in accordance with an embodiment of this invention; Figure 4 shows a cross section of the dial neck of Figure 3 in accordance h an embodiment of this invention; Figure 5 shows a cut away view of the trial rzeck of Fig and 4 attaches to a broach of the kind shown in Figures 1 and 2' in ac ccardane embOdiinent of this invention; Figure 6 shows a cross section of a trial fleck in accordance with ariaztner embodiment of this invention; Figure 7 shows a cut awa view of a trial neck of Figure 6 attached to a broach of the kind shown in Figures 1 and 2 in accordance with art embodiment of this invention; and Figure 8 shows an inferior view the trial neck of Figures 6 and 7 in accordance with an embodiment of this invention. ;DETA I LED DESCRIPTION ;Embodiments of the present invention are described in the following with reference to the accompanying drawings. ;S ;Figure 1 shows a trial neck 100 an a broach 200 in accordance with an embodiment of this invention. The trial neck 100 is removably connected to the broach 200 using connection features that will be described below in more detail. ;In this embodiment, the broach 200 is sized and shaped for insertion into the intramedultary canal of a femur during a hip replacement procedure. The broach 200 has a stem 202. The stern 202 is elongate. The stem 202 has a proximal end 206. The stem 202 as has a tip 204 located at a distal end of the broach 200. An outer surface of the stem 202 may be provided with features such as ridges 208 for removing bone from the inner wall of the intrarnedullary canal. ;In this embodiment, the trial neck 100 has an elongate neck part 2. The elongate neck part 2 extends along a neck axis 102 of the trial neck 100. The neck axis 102 may correspond to the neck axis of the prostheses to be installed following the trialing procedure, The 20 elongate neck part 2 has a proximal end 4. ;In this embodiment, the proximal end 4 may be inserted into an opening in a trial head, to connect the trial neck 100 to the trial head during the trialing procedure. The proximal end 4 of the elongate neck part 2 may be provided with one or more connection features for implementing the attachment of the trial head to the proximal end 4 of the elongate neck part 2. In the present embodiment, the proximal end 4 of the elongate neck part 2 is substantially cylindrical and the connection feature 104 comprises an annular ridge 104-that receives a rubber 0-nng for mating with a corresponding connection feature of the trial, head. ;The trial neck 100 also has a base 106, The base 106 is located at a distal end of the elongate neck part 2. The elongate neck part 2 extends between the proximal end 4 and the base 106, The vial neck 100 c embodiments be provided with one or more openings (e.g. see the opening 108 in Fi ure 1):which are in fluid communication with an interior of the trial neck 100. These openings can aid in the cleaning of the trial neck 100 before anti. after a procedure. The openings will be described in more detail below in relation to Figures 3 to 8. ;During the dialing procedure, the trial neck 100 may he connected to the broach 200. ;The connection of the trial neck 100 to the broach, 200 may be performed while the stem 2032 f e broach 200 is located in the intramedullary canal of a bone (the femur, in the case of a 10 hip replacement procedure) To implement the connection of the trial neck 100 to the broac d the broach 200 arc each provided with connection features. , the trial neck ion features will first be described in relation to e 2. The connection features of embodiments of the trial neck 100 will thereafter be described in relation to Figures 3 to 8. ;Figure 2 shows a cross section of a broach 200 of the kind shown in Figure The broach 200 has proximally facing surface 26 located at the proximal end 206 of the 202. The proximally facing surface 26 may be substantially planar. ;The bro h inc! spigot 28. The spigot 28 extends proxim ally' from proximall ocated at the proximal end 206 of the stem 202, The spigot 28 is configured (sized and shaped) for receipt in an opening 8 of tile trial neck 100 to be described below. The spigot 28 may be provided with features such as a cut-out 210. These features may be used to engage with connection features located in the opening 8 of the trial 100. ;The proximal enct 206 of the202 may be provided with opening or slot 24 for ring an arc-rotation feature 14 of die trial neck 100, lra ttais embodiment, the opening or slot 24 is located. laterally with respect to the spigot 28, although it is also envisaged that the opening or slot 24 may be located medially with respect to the The broach 200 may comprise medical grade stainless according to embodiments of this invention may similarly compris steel or may comprise a polymer. ;Figure 3 sows the trial neck 100 of Figure 1 in isolation, trial neck 100 Trade stainless e 4 shows a cross section of the trial Dee res 3 and 4 connected the b The base 106, s, shows a cut away VIeW of the trial neck of res 1 an 2 teal at a distal end of the, elongate neck part 2, has a distally facing underside 6. The underside 6 of the base 106 may be substantially planar. The proximal end 206 of the stem 202 of the broach 200 may include a proximally facing surface 26 (this may be referred to as the calcar surface of the broach 200). The proximally facing surface 26 may be substantially planar. When the trial neck 100 is connected to the broach 200, the underside the base 106 may rest against the proximally facing surface 26 of the proximal end 206 of the stem 202. ;As can be see to cross section of igure 4, the trial neck 100 includes an ope The opening 8 extends (in a proximal direction) into the trial neck 100 from the distally acing underside 6, The opening 8 is configured to receive the spigot 28 of the broach 200, 20 for connecting the trial neck 100 to the broach 200. "the opening 8 and the spigot 28 may extend along a common axis when the trial neck 100 is connected to the broach 2(10. The axis along which the opening 8 and the spigot'extend may be substantially perpendicular to the underside 6 of the base 106 and the proximally facing surface 26 of the proximal end 206 of the stem 202. note that the along which the opening 8 and the spigot extend may or may not be substantially parallel to the neck axis 1.02. ;The above mentioned anti-rotation feature 14 may extend from the distally g underside 6 of the trial neck 100. [n this embodiment, the anti-rotation feature of the etk 0 comprises a protrusion 14. The protrusion 14 extends distally from the underside 6 of the base 106. The protrusion 14 may be substantially cylindrical as shown in the figures, or may be any other regular or irregular shape (e.g, the protrusion 14 may have a square or hexagonal cross section). The opening or slot 24 may be shaped so as to accommodate the protrusion 14. As shown in Figure 5, when the trial neck 100 is connected to the broach 200, the protrusion 14 is received within the opening 24. In the present embodiment, the opening or slot 24 comprises an open ended slot. ;In this embodiment, the trial neck includes four openings 108, 118, 128, 138, which are in fluid communication with an interior of the triad neck 100. In particular, each opening 108, 118, 128, 138 extends between a side wall of the opening 8 and an outer surface of the trial neck 100 ftc openings 108, 118, 128, 138 may extend along axes which are substantially perpendicular to the axis along which the opening 8 extends. Accordingly, the openings 108, 118, 12.8, 138 may extend radially outward with respect to the axis along which the opening 8 extends. The openings 108, 118, 128, 138 in this embodiment include an anterior opening, 108, a posterior opening 138, a lateral opening 128 and a medial opening 118. As noted above, these openings can aid in the cleaning of the trial neck 100 before and after a procedure. One or more pairs of such openings 108, 118, 128, 138 may extend along a common axis, to improve the flow of fluid through the interior of the trial neck 100 for flushing out any material located in the opening 8. For instance, in the present embodiment, the anterior opening 108 and the posterior opening 138 extend along a common axis, as do the lateral opening 128 and the medial opening 11$ As can be seen in the cross section of Figure 4, the trial neck 100 includes a collet 120. The collet 120 is located in the opening 8. The collet ILO is provided to facilitate connection of the trial neck 100 to the broach by engaging with the spigot 28 when the spigot is inserted into the opening 8. ;In this embodiment, the collet 120 has a plurality of fingers 122A, 12213, 122C, 1221). ;The fingers 122A, 12213, 122C, 122D are configured to deflect away from the axis along which the opening 8 extends on insertion of tae spigot 28 into the opening 8. In particular, the fingers 122A, 1228, 122C, 122D are resiliently deflectable away from the axis along which the opening extends 8. This may allow the fingers 122A, 122B, 122C, 1221) to grip the spigot 28 when it is received within the opening 8. The fingers 122 may be shaped to conform with the surface of the spigot 28 which they engage. For instance, in the embodiment &town in Figure 5, the fingers 122 are curved around the axis along which the opening 8 and the spigot 28 extend, so as to conform with the substantially cylindrical surface of the spigot 28. ;in this embodiment, the fingers 122A, 12213, 1,220, 122D each point proximally, although it is envisaged that the fingers may poim distally in other embodiments (e; g: see the embodiment of Figures 6 to 8 to be described below). in the present embodiment, the collet 0 has ftaur fingers including: an anterior/lateral finger 122C; an anterior/medial finger posterior/lateral finger 1228, and a posteriorlmedial finger 122A. It is envisaged that in other embodiments a different number (e.g. two, duea, five, six) of fingers 122 may be provided. ;The fingers 122 may be equally spaced around a circumference of the 20. The fingers 122 may be separated by intervening gaps 126, to allow the fingers 122 to deflect freely without interfering with each other, One or more of the openings 108, 118, 128, 138 may be aligned with a respective intervening gap 126. This can improve fluid flow into out of) the opening 8 via the openings 108, 118, 128, 138. ;In the present embodiment. a base 123 of the co let 120, froth which the fingers extend proximally, is located at a distal end of the collet 1'20. The base 123 of the collet 12') may sit flush with'the distally facing underside 6 of the trial neck 100. The base 123 of the -collet 120 may conform with the shape of the opening 8 (e.g. base 123 may be annular/ring shaped, in the present embodiment). ;The collet 120 may be integrally formed with the remainder of the trial neckin such examples, the trial neck 100 may be manufactured by moulding using NEM or PIM moulding) or by 3D printing. As noted above, the trial neck may comprise a metal such as a medical grade stainless steel, or may comprise a polymer Ic is envisaged tha. the collet 120 may be provided as a separate component, is fitted inside e opening 8. For instance, in the present embodiment, the collet 120 is held within the opening by a friction tit. The friction fit may, be formed between the side of opening 8 and an outer (e.g. thremnferential) surface 125 of the base 123, When the collet 120 is provided as a separate component fitted inside the opening 8, the collet 120 may be formed from either the same material as the remainder of the trial neck 100, or alternatively from a dif ererriauterial. For instance, when the trial neck 100 Comprises a meta:;, the collet 120 may comprise -a metal or a polymer, and when the trial neck comprises a polymer, the collet 120 may comprise a metal or a polymer. envisaged that when both the trial neck 100 and the collet 120 both comprise a metal or comprise a polymer, these two components could comprise different metals or polymers. ;5When the trial leek 100 and tlic collet 120 comprise different terials, this cap allow the chosen 1 als to be particular soiled to the roles components fulfil. By way of example, the collet 120 may comprise a material that is more pliant than the material used for the remainder of the trial neck 100 to allow the fingers 122 to deflect resiliently, as described above. ;ure shows a cross section of a trial neck 100 in accordance with an embodiment of this invention, Figure 7 shows a cut away view of a trial neck 100 of Figure 6 attached to a broach 200 of the kind shown in Figures 1 and 2. Figure 8 shows an inferior view the trial neck 100 of Figures 6 and 7. The trial neck 100 has some similarities with the trial neck of Figures 1 to 5, and only the differences will be described in detail below. ;As can be seen in, for example,Figure 6, the trial neck 0 this embodiment is not provided with an anti-rotation device on 14 described above. ;Nevertheless, it is ctavisaged that the pr art embociiraint may be provided with an anti-rotation device (e.g. the protrusion 14). Likewise, it is envisaged that the trial neck 100 of Figures 1 to 5 may not be provided with an anti-rotation device. ;mbodiment, the collet 120 located in the opening is formed In h with the remainder of the trial neck material as the reminder of the trial Accordingly, the collet 120 comprises the same 100 (e.g. a metal or polymer as noted above), The collct 120 may be manufactured by moulding (e.g. cisia g MEM or PIM moulding) or b). prin Nevertheless; it is again envisaged that the collet 120 may he provided as a separate ci mponent,which is fitted inside the opening 8 as described above. In such embodiments, the ccllei 120 may comprise a different material to the remainder of the trial neck 100, and tamed within the opening 8 by means of a friction fit. ;As described above, a trial neck 100 according to embodiments of this invention may have a collet 120 including a plurality (two, three, four, five, six etc,) of fingers 122. In the present embodiments, the collet has two fingers 122 including a medial finger 122E and a lateral finger 122F. As with the fingers 122A, 12213, 122C, 122D, the fingers 172E and 122F may be shaped to conform with the surface of the spigot 28 which they engage. For instance, as shown in Figure 8, the fingers 122 may be curved around the axis along which the opening 8 and the spigot 28 extend, so as to conform with the substantially cylindrical surface of the spigot 28. ;In this embodiment, the fingers 122E, 122F point distally, The fingers 122E, 122F may terminate close to (e.g. flush with) a plane containing the distally facing underside 6 of the base 106. A part of the opening 8 located towards the distally facing underside 6 of the base 106 may be flared outward, to produce a region 88 having larger lateral dimensions than the proxintai part of the opening 8, This region 88 may accommodate the outward deflection of the fingers 122F, 122F when the spigot 28 is inserted into the opening 8. ;The trial neck 100 of Figures 6 to 8 may' also include openings 148, 158, which may perform the same function as noted above in respect of the openings 108, 118, 128, 138. These openings may include a lateral opening 148 and a medial opening 158. The openings 148, 158 may each extend in a posterior-anterior direction and pass completely through the trial neck W0. The openings 148, 158 may be located at a periphery of (e,g, region 88 of) the opening 8, so that fluid passing through the openings 148, 158 may enter the opening 8, and vice versa. ;It is envisaged that the trial neck 100 may alternatively have openings such as openings 108, 118, 128, 138. Likewise, the trial neck 100 of Figures 1 to 5 may have openings such as the openings 148, 158. ;According to an embodiment of the invention, there may be providea a kit for use in orthopaedic surgery, comprising one or more trial necks 100 and one or more broaches 200 of the kind described herein. In kits including a single trial neck 100 and multiple broaches 200, at least some of the broaches 200 in the kit may be of different sizes to the other broach(es) 200 in the kit, in kits including multiple trial necks 100 and a single broach 200, at least some of the trial necks 100 in the kit may he of different sizes to the other trial neck(s) 100 in the kit, in kits including multiple trial necks 100 and multiple broaches 200, at least some of the trial necks 100 and/or broaches 200 in the kit may he of different sizes to the other trial neck(s) 100 and/or broach(es) 200 in the kit. ;The embodiments shown in the drawings are described in relation to the use of the trial neck 100 and broach 200 with the left leg of a patient, It will be understood that the trial neck 100 and the broach 200 may be used with the right leg of a patient. It follows from this that certain features of the trial neck 100 which have been described as being anteriorly or posteriorly located in the case of use with the left leg of a patient would become posteriorly or anteriorly located in the ease of use with the right leg of a patient. By way of example only: * in the case of use with the right leg of a patient, the above described anterior opening 108 would be referred to instead as the posterior opening and the above described posterior opening 138 would be referred to instead as the anterior opening; and ^ in the case of use with the right leg of a patient, the above described anterior/lateral.

finger 122C would be referred to instead as the posterior/lateral finger, the above described anterior/media: finger 122D would be referred to as the posterior/medial finger, the above described posterior/lateral finger 122B would be referred to as the anterior/lateral finger, and the above described posterior/medial finger 122A would be referred to as the anterior/medial finger.

A method of using the trial neck 100 and broach 200 for performing orthopaedic surgery may include inserting the elongate stern 202 of the broach 202 into an intramedullary canal of a bone, such as the femur. The intramedullary canal may he prepared for the introduction of the broach 200 by cutting away the femoral head and neck and by initiating an opening at the proximal end of the bone. This opening may then be widened by reaming away bone from the opening and interior of the intramedullary canal, until the broach 200 can be correctly received.

The broach 200 may substantially as described above. Accordingly, the broach 200 may include a spigot 28 extending proximally frorn a proximal end 206 of the elongate stein 202 for connection to a trial neck 100, The method may also include connecting to the broach 200.

ial neck 100 be substantially as described above. Accord neck may include sin ci lag along a neck axis 1 100, a connection feature located tt a proximal end 4 of the elongate neck part connecting the trial neck 100 to a trial head, a base 106 located at a distal end of th neck part 2, the base 106 having a distally facing underside 0, an opening 8 extending into the trial neck 1.00 from the distally facing underside and a collet 120 located in the opening 8 for connecting the trial neck IOU to the spigot 28.

Connecting tlae trial neck 100 to the broach 200 may include inserting; the spigot 28 into the opening 8. When inserted into the opening 8, the spigot 28 may ma}= engage with the collet 12 as described above.

The method may also include cleaning; the trial fleck 100 by passing a fluid through the at least one opening 108, This cleaning process may ed out before and/or after the use of the trial neck 100 in the procedure.

The orthopaedicsurgery may be a hip replacenrentprocedure.

eeordingly, there has been eribed a trial neck, kit and method for ordaopaedie fiery. I=lie trial neck includes an elongate neck part extending along a neck axis of the trial neck. The trial neck also includes a connection feature located at a proximal end of the elongate neck part for connecting the trial neck to a trial head. The trial neck further includes a base located at a distal end of the elongate neck part. The base has a distally facing underside. The trial neck also includes an opening extending into the trial neck from the distally facing underside. The trial neck further includes a collet located in the opening for connecting the trial neck to a spigot of a broach. The kit includes the trial neck and a broach. The method includes connecting the trial neck to a broach by inserting a spigot of the broach into the opening.

Aspects of the invention are s out in thetfFrllocving nu uses.

rethod of pert ming 0 opaedic surer thestzethod Fp ng, inserting an elongate e; of a broach into ar eduilary canal of a bone the broach comprises a spigot extending proximally from a froxima! end of gate stern for connection to a trial neck; and connecting a trial neck to the broach, wherein the trial neck corn an elongate neck part extending along a neck axis of the t e k; a connection feature located at a proximal end of the elongate n ck part for connecting the trial neck to a trial head; a base located at a distal end of the elongate neck a the base having a distally a' ing underside; an opening extending into the trial neck from the distally facing underside; and a collet located in the opening for connecting the trial neckto said spigot, wherein said connecting the trial nee e breach compr serting the into the opening.

The method of clause 1, wherein the opening extends along", an axis, wherein the collet comprises a plurality of fingers, and w nett tlae fingers deflect away from the axis along which the opening extends, on in e spigot into the opening.

The method of clause 2. wherein the fingers deflect resi resilientlyaway from along which the opening extends, for griping the spigot when it received within c opening.

The method of any of clauses I tad 3, the trial neck comprising least one further opening, 1Nher which the collect comprising (dearth' opening. one further opening extends b the opening in ieated and an outer surface of the trial neck, the method farther he trial neck by passing a fluid through said at least one father The method of clause 4 when dent on clause 2 or clause 3, in which the fingers of the collet are separated by intervening gaps, and wherein at least one said further opening is aligned with a said intervening gap, the method further comprising passing said fluid through said at least one further opening and through said intervening gap aligned with the further opening.

6. The method of any of clauses 1 to 5, wherein the orthopaedic surgery comprises a hip replacement procedure.

Although particular embodiments of the invention have been described, it will be appreciated that many modifications/additions and/or substitutions may be made within the scope of the claimed invention.

Claims

CLAIMS1, A trial neck for orthopaedic surgery, the trial neck comprising: an elongate neck part extending along a neck axis of the trial neck; a connection feature located at a proximal end of the elongate neck part for connecting the trial neck to a trial head; a base located at a distal end of the elongate neck part, the base having a distally facing underside; an opening extending into the trial neck from the distally facing underside; and a collet located in the opening for connecting the trial neck to a spigot of a broach.
2. The trial neck of claim 1, wherein the opening extends along an axis, wherein the collet comprises a plurality of fingers, and wherein the fingers are configured to deflect away from the axis along which the opening extends, on Insertion of the spigot into the opening.

3, The trial neck of claim 2, wherein the fingers are resiliently deflectable away from the axis along which the opening extends, for griping the spigot when it is received within the opening.

4, The trial neck of claim 2 or claim 3, wherein the fingers point distally.

5, The trial neck of claim 2 or claim 3, wherein the fingers point proximally. 25 6, The trial neck of any of claims 2 to 5 comprising exactly two said fingers 7. The trial neck of any of claims 2 to 5 comprising exactly four said fingers, 8, The trial neck of any preceding claim comprising at least one further opening, Wherein the at least one farther opening extends between the opening in which the collect is located and an outer surface of the trial neck.9. The trial neck of claim 8 comprising a plurality of said further openings, The trial neck of claim 8 or claim 9, wherein the or each opening xtends ratfiall outward with respect to the axis along which the opening in which the collet is located extends, The trial e of any of claims $ ie10 when dependent any of claims 2 to 7, in which the fingers of the c are separated by intervening gaps, and wherein at least one said further opening is aligneu with a said intervening gap.l 2. The trial neck of any preceding claim, wherein the collet comprises a dilli;rent material to a remainder of the trial neck.The trialof any preceding the collet c rnprises 14, T neck of ar preceding claim, wherein the trial neck comprises a in 15. The trial neck of any of claret: by a friction fit.15. The trial neck of any of trial neck, tin et is held within the opening herein e collet is integrally formet 14. The trial /leek of any preceding claim, further comprising an anti rotation feature for 17. The trial neck of claim 16, wherein the ant comprises a protru extending distally from the distally facing underside of the base for insertion in an opening in,a proximal end of the broach The trial neck of any preceding claim,wherein the o paedie s comprises a hip replacement procedure, preventing ro of the trial neck relative to a broach when the trial neck is connected to the braac rthopaedie surgery, the kit comprising the trial neck of any preceding claim and a broach.20. The kit of claim g a trial n according to any laims I to l3 and a plurality of said broaches, wherein at least some of the broaches in the k are of s to t ach(es) Yr t kit.21. The kit of claim 19 or claim 20, i omprising a plurality said trial necks according to any of claims 1 to 18 and a plurality of said broaches, wherein at least sonic of the trial necks and/or broaches in the kit are of different sizes to the other trial neck(s) and/or broach(es) in the kit.