阅读说明：本技术 一种用于安装植入物的工具组件 (Tool assembly for installing implant ) 是由 G·克拉克 F·曼根 F·斯托克曼 A-P·C·韦斯 A·L·拉德 B·博兰 于 2020-04-24 设计创作，主要内容包括：一种用于将杆植入物安装到骨骼中的工具组件,其包括杆状准备工具(1)和不同尺寸的多个杆状拉刀(2、3、4、5、6),所述杆状准备工具(1)具有远端顶部(32)和沿其长度的多个切割齿(31)。每个拉刀具有远端顶部和沿其长度的多个切割齿(31)。所述准备工具(1)比最小的拉刀更短,每单位长度具有更多的切割齿(31),并且具有更锋利的远端顶部(32)。(A tool assembly for installing a rod implant into a bone, comprising a rod-like preparation tool (1) and a plurality of rod-like broaches (2, 3, 4, 5, 6) of different sizes, the rod-like preparation tool (1) having a distal tip (32) and a plurality of cutting teeth (31) along its length. Each broach has a distal tip and a plurality of cutting teeth (31) along its length. The preparation tool (1) is shorter than the smallest broach, has more cutting teeth (31) per unit length, and has a sharper distal tip (32).)

1. A tool assembly for installing a rod implant into a bone, comprising:

a rod-like preparation tool (1) having a distal tip and a plurality of cutting teeth along its length; and

a plurality of rod-like broaches (2-6) of different sizes, each broach having a distal tip and a plurality of cutting teeth along its length,

wherein the preparation tool is shorter than the smallest broach, has more cutting teeth per unit length, and has a sharper distal tip.

2. The tool assembly according to claim 1, wherein the preparation tool and the broach comprise proximal handle (20) ends with grooves (21) to aid gripping.

3. A tool assembly according to claim 1 or 2, wherein the preparation tool and the broach each comprise a flange (25) at a distal end of a proximal handle of the tool.

4. Tool assembly according to claim 3, characterized in that the flange (25) is truncated (27) on one side of the handle.

5. Tool assembly according to any one of claims 1 to 4, characterized in that the distal head (30) of the preparation tool (1) and the broach (2-6) are curved in the palmar direction and substantially straight in the dorsal direction.

6. Tool assembly according to any one of claims 1 to 5, further comprising at least one dual purpose tool (7, 8).

7. Tool assembly according to claim 6, characterized in that the dual purpose tool (7) has a head providing both files (52) and broaches (53).

8. Tool assembly according to claim 6 or 7, wherein the dual purpose tool (8) comprises a lever (64) for lifting the bone.

9. The tool assembly according to claim 8, wherein the lever includes a distal engagement slot (63).

10. The tool assembly according to any preceding claim, further comprising a rod insertion tool (9) having engagement features (40) for engaging with corresponding engagement features of an implant rod (100, 111) to transfer a force applied to the rod insertion tool to the rod implant.

11. The tool assembly according to claim 10, wherein the engagement feature comprises a bullnose feature (40).

12. The tool assembly according to claim 10, wherein the engagement feature comprises a ball (91), the ball (91) configured for snap-fit into an implant, such as an implant bushing (100) of a rod (111).

13. The tool assembly according to any one of claims 1 to 12, further comprising a rod replacement tool (10).

14. The tool assembly according to claim 13, wherein the tool (10) comprises a thread (45) for engagement with a threaded socket (47) of an implant stem.

15. Tool assembly according to any one of the preceding claims, comprising a bush removal tool (95) for extracting a bush (100) assembled in a stem (111) which in turn has been implanted in the metacarpal bone, the tool comprising a threaded head (96) configured to engage in rotation the bush by means of the tool.

16. Tool assembly according to any one of claims 1 to 15, further comprising at least one trial head (70) for temporary placement in or on a bone or an implant component during preparation of the bone to receive the implant head, wherein the trial head (70) has some dimensions smaller than those of the implant head.

17. The tool assembly of claim 16, comprising a plurality of different sized trial heads.

18. A tool assembly according to claim 16 or 17, wherein the trial head includes a ball for trial insertion into an implant socket, and the ball is smaller than an implant ball for the socket.

19. Tool assembly according to any one of claims 16 to 18, wherein the trial head comprises at least one hole (71), which is not functional but identifies the trial head.

20. A kit comprising the tool assembly of any one of claims 1 to 19 and a rod implant.

21. The kit of claim 20, wherein the rod implant is configured (111) for intramedullary engagement with an end of a first metacarpal.

22. The kit according to claim 21, wherein the implant comprises an insert (100) for the proximal end of the rod.

23. Kit according to any one of claims 20 to 22, characterized in that the implant (120, 100, 110) is for a first carpometacarpal joint for spacing the trapezium from the first metacarpal bone, the implant comprising a proximal implant part having a saddle-shaped surface for translational movement on the trapezium bone, and the rod being mountable to the proximal part with an articulated coupling, such as a ball-and-socket joint.

24. The kit as recited in claim 23, wherein the proximal end portion (120) includes a head for mounting to a rod.

25. An apparatus for mounting an implant, comprising a tool assembly according to any one of claims 1 to 19 and a tray (80) for receiving a tool.

26. The apparatus of claim 25, wherein the tray comprises a base, side walls upstanding from the base, and tool support straps (81, 82) mounted to the base.

27. The apparatus of claim 26, wherein the tray comprises two support strips (81, 82) extending across the tray, each support strip comprising spaced apart recesses to accommodate part of the tools.

28. The apparatus of any one of claims 26 or 27, wherein the tools are mounted to the strip in the order in which the tools are used in the surgical procedure.

29. Apparatus according to any of claims 26 to 28, comprising a cover (87) for the tray, the cover having a strap (86) projecting inwardly therefrom to engage the tools and maintain their position in the tray.

30. The apparatus of claim 29, wherein the strip (86) of the cover is configured to engage a flat surface of the tool handle for proper closing of the cover and tool.

31. A broach (2-6) for use in preparing bone to receive an implant, the broach comprising a proximal handle (20), a shaft (28) extending from the handle and a flange (25) between the handle and the shaft and a distal head (30).

32. The broach according to claim 31, characterized in that the flange (25) is truncated (27) on one side of the handle.

33. The broach according to claim 31 or claim 32, in which the handle comprises a plurality of substantially flat sides with grooves (21) to enhance gripping.

34. The broach according to any one of claims 31 to 33, characterized in that the distal head (30) is curved in the palmar direction and substantially straight in the dorsal direction.

35. A dual use tool for reshaping a bone to receive an implant, comprising: a handle, a shaft extending from the handle (25), and a distal cutting head having a first side and a second side opposite the first side, the first side of the cutting head having file (52) features and the second side of the head having broach (53) features.

36. The dual use tool of claim 35, wherein the first side is concave shaped and the second side is convex shaped.

37. Dual purpose tool according to claim 35 or 36, wherein the distal end (50) of the tool is round, square, flat or annular.

38. Dual use tool according to any of claims 35 to 37, wherein the handle (20) comprises a plurality of substantially flat sides and comprises a groove (21) to aid gripping.

39. A dual purpose tool includes a handle (61), a shaft (60) extending from the handle, the shaft being angled relative to the handle to facilitate manipulation of small bones, and a distal tip (64) having a slot for engaging an element to facilitate leverage of the element.

40. The dual use tool of claim 39, wherein the shaft (60) is substantially flat.

41. A dual use tool according to claim 39 or 40, wherein the handle comprises a plurality of substantially flat sides (21) and comprises a groove to assist gripping.

42. An assembly fixture (140) for assembling a bushing (100) into an implant rod (111), the fixture comprising a plurality of rod holders (142) for each of a plurality of implant rod sizes and a pusher device (148) arranged to push the bushing (100) into the rod (111) upon rotation of a handle (147).

43. Assembly fixture according to claim 42, in which each holder (142) has a socket (143) for holding the distal end of the suspension bar (111) and an aligned through hole (144) for holding it in the inserted position of the bushing (100).

44. The component fixation device according to claim 42 or 43, wherein the pusher device (148) comprises a screw (150) having a pusher face (151) extending through a pusher body.

45. The assembly fixture as in claim 44, wherein the pusher body includes a pair of parallel dovetails (152) for engaging corresponding dovetail slots (145) to position the pusher screw in alignment with the rod in the retainer.

Technical Field

The present invention relates to tools used by surgeons in implantation procedures.

Background

All orthopedic implants require a tool assembly to enable installation of the implant components. The assembly will include several trial accessories for determining the size of the implant components required by the patient, as well as some specific tools to help secure the implant in the patient's joint. The implant tool assembly will typically be augmented in the operating room by common tools that are easily found in an orthopedic environment, such as drivers of various weights, osteotomes of various sizes, retractors of various types, K-wires (K-wires) and pendulum saws.

The present invention aims to achieve an improvement in the efficiency of the implantation procedure.

Disclosure of Invention

We describe a tool assembly for installing a rod implant into bone, as claimed in claim 1. Features of a tool assembly as claimed in claims 2 to 19 are also described. We also describe a kit comprising the tool assembly described in any of the examples, and a rod implant. Various aspects of the kit are described in the appended claims 20 to 24. We also describe an apparatus for installing an implant comprising any of the example tool assemblies and a tray for receiving the tools. Various aspects are described in claims 25 to 30. We also describe broaches of the various examples described in claims 31 to 34. We also describe various exemplary dual use tools as set out in the appended claims 35 to 41. We also describe an assembly fixture in various examples as claimed in claims 42 to 45.

According to one aspect, we describe a tool assembly for installing a rod implant into bone, comprising:

a rod-like preparation tool having a distal tip and a plurality of cutting teeth along a length thereof; and

a plurality of rod-like broaches of different sizes, each broach having a distal tip and a plurality of cutting teeth along its length,

wherein the preparation tool is shorter than the minimum broach, has more cutting teeth per unit length, and has a sharper distal tip.

In one instance, the preparation tool and broach include a flat proximal handle end with a groove to aid in gripping.

The preparation tool and broach may include a flange at the distal end of the proximal handle of the tool. The flange may be truncated on one side of the handle.

In some cases, the distal head of the preparation tool and the broach are curved in the volar direction and substantially straight in the dorsal direction.

The tool assembly may also include a rod insertion tool having an engagement feature for engaging with a corresponding engagement feature of the implant rod to transfer a force applied to the rod insertion tool directly to the rod implant.

The tool assembly may further comprise at least one further tool, which is a dual purpose tool. In one case a dual use tool has a head that provides both files and broaches. In another aspect, the dual purpose tool includes a lever for raising the bone. The lever may include a distal engagement slot.

The tool assembly as claimed may further comprise a rod replacement tool.

The tool assembly may also include at least one trial head for temporary placement in the bone during preparation of the bone to receive the implant head. In one instance, some dimensions of the trial head are smaller than the dimensions of the implant head. There may be a plurality of different sized trial heads.

Kits comprising the tool assemblies of the invention and rod implants are also provided. The rod implant may be configured for intramedullary engagement with an end portion of the first metacarpal. In one instance, the implant includes an insert for the proximal end of the rod.

In one case, the implant is for a first carpometacarpal joint for spacing the trapezium from the first metacarpal, the implant includes a proximal implant portion having a saddle-shaped surface for translational movement on the trapezium, and the rod may be mounted in the proximal portion with an articulated coupling means (e.g., a ball joint). The proximal portion may include a head for mounting to a rod.

We also describe an apparatus for mounting implants comprising the tool assembly of the invention and a tray for receiving the tools. The tray may include a base, sidewalls upstanding from the base, and a tool support strip mounted to the base. In one case, the tray includes two support strips extending across the tray, each support strip including spaced apart recesses to receive a portion of the tool. The tools may be mounted to the strip in the order in which they are used in the surgical procedure. The cover for the tray may have a single strip projecting inwardly therefrom to engage the tools and maintain their position in the tray.

A broach for preparing bone to receive an implant is also provided, which includes a proximal handle, a shaft extending from the handle, and a flange between the handle and the shaft. In one case, the flange is truncated on one side of the handle. The handle may include a plurality of generally flat sides with grooves to enhance gripping. The distal head may be curved in the volar direction and substantially flat in the dorsal direction.

We also describe a dual-purpose tool for reshaping a bone to receive an implant, comprising a handle, a shaft extending from the handle, and a distal cutting head having a first side and a second side opposite the first side, the first side of the cutting head having a rasp feature and the second side of the head having a broach feature. In one case, the first side is concave and the second side is convex. The distal end of the tool may be round, square, flat or annular. In some cases, the handle includes a plurality of generally flat sides and includes a groove to aid in gripping.

We also describe a dual use tool comprising a handle, a shaft extending from the handle, the shaft being angled relative to the handle to facilitate manipulation of the ossicles, and a distal tip having a slot to engage the element to facilitate leverage of the element. The shaft may be substantially flat. The handle may include a plurality of generally flat sides and include a groove to assist in gripping.

The tool assembly contains specific tools and tool features. These tools are designed specifically for a particular implant, but their novel features are also applicable to other areas of skeletal surgery.

Drawings

The invention will be more clearly understood from the following description, given by way of example only, in which:

FIG. 1 is a perspective view showing an implant including proximal and distal portions;

FIG. 2(a) is a cross-sectional view through the distal portion of the implant, and FIG. 2(b) is a perspective view of the shaft of the distal portion, FIG. 2(c) is a perspective view of the distal portion in full, and FIG. 2(d) is a perspective view of the proximal portion;

FIG. 3 is a set of views showing a portion of the distal end portion of the implant, including top plan, end, perspective and cross-sectional views;

FIG. 4 illustrates a tool assembly according to the present invention in one example;

FIG. 5 is a view of the preparation device tool of the present invention, and FIG. 6 is an enlarged view of the distal end of the preparation device tool;

FIG. 7 is a pair of side views of the broach, and in various rotational positions;

FIG. 8 is a side view of a first dual-purpose tool, and FIG. 9 is a side and plan view of a head of the first dual-purpose tool;

FIG. 10 is a pair of side views of a second dual purpose tool at different angles of orientation about its axis, FIG. 11 is an enlarged side view of the head of the tool, and FIG. 12 is a perspective view of the tool with the head and shaft arrangement in use maintained;

FIGS. 13(a) to 13(c) are complete side views of the rod insertion tool, an enlarged side view of its head, and an on-axis end view;

FIG. 13(b) is a cross-sectional side view, and FIG. 13(c) is a schematic enlarged sectional side view showing the rod insertion tool in use;

FIG. 14(a) is a side view, FIG. 14(b) is a plan view, and FIG. 14(c) is an enlarged side view of a head portion of a rod changing tool;

FIG. 15 is a photograph of a prior art tool;

FIG. 16 is an enlarged view of the handle end of some of the tools;

FIG. 17 is an enlarged view of the flange of some of the tools;

FIG. 18 is a set of detail views of the flange of some tools;

19(a), 19(b) and 19(c) show an alternative rod insertion tool in use;

FIG. 20(a) is a side view of a bushing-changing tool, and FIG. 20(b) shows the head of the tool engaged with the bushing; and

FIG. 21 is a view of a trial head used during implant installation;

FIG. 22 is a view of the instrument tray, and FIG. 23 is a view of a cover for the instrument tray of FIG. 22; and

fig. 24(a) is a perspective view of an intra-operative assembly, and fig. 24(b) is an end view of one component of the assembly.

Detailed Description

One example of an implant that may be installed using the tool assembly of the present invention is shown in fig. 1-3. Referring to fig. 1-3, implant 1 has distal and proximal portions 120 with insert 100 in shaft 110. In this case, the implant 1 is intended for a mammalian first carpometacarpal joint for spacing the trapezium bone of the joint from the first metacarpal bone of the joint while allowing translational and rotational movement of the first metacarpal bone relative to the trapezium bone. The distal portion 110 is configured for intramedullary engagement with an end of the first metacarpal. The proximal portion 120 has a curved saddle-shaped pedestal 122 having a proximally facing surface 124 for sliding over or traversing the trapezium bone. As is known, the articulated coupling means comprise a neck 123 bridging the saddle 122 to the ball 121. This allows for controlled articulation of the trapezium and first metacarpal.

The insert 100 may have a cushioning interface feature, in this case a flange 105 having a contoured, proximally-facing surface 101. At the distal end of this surface there is a shoulder 102 which acts as a key for engaging the insert 100 in the rod 111 and preventing rotation of the insert in the rod, and surrounds the socket 103 with an edge 106 to receive the articulated coupling ball 121. The ball 121 (see especially fig. 2(d)) has a snap-fit engagement in the socket 103, behind the socket's edge 106, to enable intraoperative assembly of the articulating hemi-arthroplasty and also to prevent device disassembly in vivo. The sockets may be centered or offset in any direction or angle, as desired.

More distally, the insert 100 comprises an annular locking edge 104 for snap-fitting into a corresponding groove of the recess 115 of the stem 111 accommodating the insert 100. The engagement of the insert 100 into the stem 111 is effective due to the elasticity of the insert material and the fact that there is full surface-to-surface contact between the edge 104 and its corresponding engagement surface within the stem 111 in a snap-fit manner. The insert is keyed by a shoulder 102 to prevent rotation and potential backside wear.

Referring to fig. 4, a tool assembly for installing an implant (such as the implant of fig. 1-3) is shown. The tool assembly in this example includes:

preparing the device 1 (fig. 5 and 6);

a set of five broaches 2, 3, 4, 5, 6 of different sizes (fig. 7);

a first dual-purpose tool 7 (fig. 8 and 9);

a second dual-purpose tool 8 (fig. 10, 11 and 12);

a rod insertion tool 9 (fig. 13(a), 13(b), 13 (c)); and

the rod replacement tool 10 (fig. 14(a), 14(b), and 14 (c)).

Preparation apparatus 1 (FIGS. 5 and 6)

Referring to fig. 5 and 6, the preparation device 1 has a cutting head 30 and facilitates a first incision into the metacarpal bone and eliminates the need for a drill or the like by the surgeon prior to deployment of the first broach 2. Furthermore, the geometry of the cutting head 30 of the preparation device 1 is modelled on the geometry of the smallest broach (broach 2) in the tool assembly. The device 1 is smaller and shorter, has more cutting teeth 31 per unit length, and has sharper points 32, but the necessary curved volar, flat dorsal geometry of the broach and implant. The absence of a toothless marrow compression distal tip at the distal tip of the preparation device is a feature of the broach. In this case, the head 30 has 17 cutting teeth 31, and generally preferably has in the range of 12 to 22, and more preferably in the range of 14 to 20 teeth.

The net effect is that the preparation device 1 penetrates further than a drill bit or the like, can be used to position the initial cut more accurately and, above all, reduces the effort required by the first broach 2. This is a particularly important benefit to surgeons with low or weak hand strength.

Broach (Picture 7)

Broaches 2, 3, 4, 5, 6 (referred to as broaches a to E) match the implant stem 111 geometry. Thus, the end user can use the broach as a trial rod. When the surgeon has completed broaching the metacarpal cavity, there is no need to place a separate trial rod in place to assess the rod's fit, as the broach itself will provide this clinical information.

In addition to the tools described, a trial implant head 70 (fig. 22) may also be used during surgery, as described in more detail below.

To install the implant, a first incision is made in the metacarpal using the preparation device 1. By virtue of its cutting tooth density and the fact that the preparation device geometry is very similar to that of the smallest broach (dimension a, 2), the preparation device also helps the surgeon to create the exact position and orientation of the broach, thereby creating the rod implant within the metacarpal. One or more broaches 2, 3, 4, 5, 6 are then used to broach the metacarpal cavity. The broaches are used in increasing order of size. Therefore, dimension a (2) follows after use of the preparation device. For any given metacarpal, the surgeon decides whether or not a continuous broach size is required based on the surgeon's perception in broaching and/or using X-ray images. After broaching, the rod insertion tool 9 is used to insert the rod portion 110 of the implant into the metacarpal cavity until the metacarpal rod implant 110 is positioned flush or just protruding from the resected metacarpal. This is facilitated by the close relationship between the broach and rod implant, and the surgeon is able to estimate the final position of the base of the rod relative to the resected metacarpal from the position of the final broach he or she uses.

First dual-purpose tool 7 (FIGS. 8 and 9)

Referring to fig. 8 and 9, the first dual purpose tool 7 has two features, a rasp 52 and a broach 53. The rasp 52 on the concave side can be used to sculpt the trapezium bone to the precise radius of the implant head 120. The convex side of the tool 7 carries broach-like teeth 53 which can be used to remove the incidental osteophytes or other protrusions encountered during sculpting of the trapezium.

As mentioned above, the head 50 of the tool has dual-purpose capabilities. It has a shaft 51 that is tapered or otherwise reduced in diameter to facilitate access to small joints.

The concave side 52 of the head 50 has a rasp configuration and is designed to sculpt the trapezium bone into the shape of the implant head. The convex side 53 has a broach structure for removing bone tags and is designed to cut on a pull stroke rather than a push.

Other uses include maxillofacial surgery where bone reconstruction is required but the surgeon does not want to have to continually remove and replace tools. For example, the first dual-purpose tool 7 may be inserted into a body cavity and used for a rasping function, left in place but rotated 180 degrees, and then used for a broaching or bone reshaping function.

The tool 7 can be used to modify the geometry of any bone's outer or inner surface depending on the bone's geometry, cutting surface and the distal end of the tool, the novel dual function head being easy to use.

The shape of the distal end of the tool 7 may be circular, square, flat or annular, depending on the desired anatomical geometry to be produced by its use.

The distal cross-section above and below the centerline may have one geometry on one side and another geometry on the other, i.e., annular on one side and flat on the other side.

Second Dual-purpose tool 8 (FIGS. 10, 11 and 12)

Referring to fig. 10, 11 and 12, the second dual-purpose tool 8 is used as a metacarpal elevator to move tissue aside and present the metacarpal to the surgeon for resection. It includes a stem 60 and a head 64 having a keyhole feature 63. A keyhole feature 63 is located at the distal end of the head 64 of the second dual purpose tool 8 and may be used to separate the trial head (70) from the implant stem, as shown in fig. 12.

The tool 8 may be used, for example, as a metacarpal elevator and for presenting the metacarpal to the surgeon for resection. The shaft 60 is flat and angled relative to the handle 61 and provides optimal access to both the metacarpal bones and the fulcrum location. The head 64 is curved to match the curvature of the metacarpal.

In addition, keyhole slot 63 at the distal end of head 64 matches the radius of the neck of implant stem 111 and can be used to pry trial head 70 out of bushing 100 when the surgeon is ready to install implant head 120, as shown in fig. 12. Typically, the head of the tool 8 is a multi-purpose claw that acts as a holder or grasping lever for remote control of an item.

Other uses of the second dual-purpose tool 8 include: a) manipulating any small bone during surgery, such as the second to fifth metacarpals; b) removing the plate in facet joint surgery by levering the plate away from the bone using a tool; c) removing the bone plate with the screw in situ, wherein the keyhole may be positioned around the nail or screw while the plate is leveraged away from the bone; d) the screw is removed from the bone with the slot/keyhole 63 used to pry the screw out of the bone, which may be of poor quality but with some fixation.

Rod inserting tool 9 (FIGS. 13(a), 13(b) and 13(c))

The internal features of the head 40 of the rod insertion tool 9 capture the contour and depth of the bushing flange 100 and these features allow the distal portion of the tool head to bottom out on the base of the metacarpal rod implant 111. The distal head 40 of the tool 9 is located at the base of the stem 111. When the surgeon manipulates the rod 111 into the bone, the bushing 100 will not be damaged because if a driver is used in conjunction with the rod insertion tool 9, the force is transferred from the metal head of the rod insertion tool 9 to the metal base of the rod 111.

The distal portion of the tool head 40 is contoured beyond the contour of the base of the metacarpal stem implant 111. These design features ensure that bushing 100 cannot be inserted below flush into bone when the metacarpal stem implant 111 is already in a position flush or protruding only from the resected metacarpal.

The bullnose at the distal end of the rod insertion tool 9 is smaller than the inner diameter of the bushing 100 at the snap-fit location, and since the rod insertion tool 9 tightly encases the exterior of the bushing 110, there is no damage to the snap-fit of the bushing 110 with the ball of the head 121.

Rod changing tool 10 (FIGS. 14(a), 14(b), and 14(c))

If necessary, the rod 110 may be removed from the metacarpal cavity using the rod replacement tool 10. If the bushing 100 is removed from the shank 110, the fine metric threads 45 of the tool may engage the fine metric threads 47 in the shank 111 (see fig. 13(b)), and, if desired, the shank 111 may be removed. The rod changing tool 10 has a full circular flange 46 for the driver to assist in rod ejection, regardless of how deep the threads engage each other.

If implant rod 111 is not provided with polymeric bushing 100, rod changing tool 10 may be used to position rod 111 and facilitate the striking of rod 111 into place. The same applies to a rod without a polymer bushing, but instead has a metal socket with mating threads at the distal end of the socket for the rod replacement tool 10.

Handle with groove and flange (fig. 16 to 18)

Fig. 15 shows a circular serrated hand wheel located at the proximal end of many prior art orthopedic broaches. The rounded proximal end of the prior art (along with the driver, for tool removal) is grasped by the surgeon and may promote twisting of the tool, which may result in a larger than desired hole in the bone. The hole created by the broach cutting head should correspond to the geometry of the implant. Prior art broaches having a handle of the circular type are twisted to achieve a grip in the bone.

In the tool assembly, the tool has a flat elongated proximal handle 20 with a groove 21 to aid in gripping, as shown in fig. 16 and 17. Thus, the tool facilitates axial movement, and this results in a hole in the bone that more precisely conforms to the geometry of the broach cutting head, and thus the implant.

The preparation device 1, the broaches 2, 3, 4, 5, 6 and the rod changing tool 10 all have flanges 25, 46 at the distal end of the handle 20, as shown in fig. 16 to 18. The flange 25 (and 46 on the tool 10) enables the driver to be used for tool extraction purposes, if desired. They also serve as stops for the surgeon's hand and are coupled with flats on the handle carrying tool indicia 26 and serving as a thumb grip, the priming device 1 and broaches 2, 3, 4, 5, 6 facilitating stable axial forward movement.

This means that the tool of the present invention requires little or no impact compared to other tools. This reduces potential fracture damage to the bone during surgery, which is observed in clinical practice using conventional tools.

As shown in fig. 18, the flange 25 and all broaches 2, 3, 4, 5, 6 of the preparation device 1 are truncated to provide a non-circumferential side 27 of 270 ° on the volar side.

This facilitates the surgeon by being able to use the tool at an angle that is very consistent with the axis of the metacarpal during surgery. This feature further reduces any tendency of the surgeon to twist the tool, and it also allows sufficient space on the distal side of the flange for the impactor to assist in tool withdrawal, if desired.

Rod inserting tool 90 (FIGS. 19(a), 19(b) and 19(c))

An alternative rod insertion tool 90 includes a ball 91 having a diameter smaller than the diameter of the implant head ball, but just sufficient to provide a light snap-fit (light snap-fit). This light snap fit provides an attachment between the tool 90 and the implant rod-bushing assembly 110 so that the surgeon can use the tool to transport the implant directly from the staging area to the implantation site.

Bushing changing tool 95 (FIGS. 20(a) and 20(b))

The tool assembly may additionally include a tool 95 to withdraw the bushing 100 assembled in a stem 111 which is also implanted in the metacarpal. Removal of the bushing may be required when access to the threaded portion 47 of the rod is required to remove or replace the rod. The threaded head 96 of the tool 95 is configured for a double-start tapered thread, wherein the threads of the thread engage the snap-fit diameter of the socket within the bushing 100. Tool 95 is threaded into bushing 100 until resistance is felt at the point where bushing 100 is easily pried out of lever housing 112 (as shown in fig. 20 (a)).

Test head 70 (fig. 21)

Trial head 70 conforms to the geometry of the associated implant head 120, in addition to having two through holes 71 through the saddle, and having two letter designations suitable for each of the four trial head types to be laser etched into the base. The through hole 71 helps to distinguish the trial head 70 from the part 120 of the implant.

The ball diameter of trial head 70 is also slightly smaller than the ball diameter of implant head 120 so that the snap fit of bushing 100 is not stressed. Although the ball diameter is slightly reduced, by increasing the neck length of the trial head 70, the distraction distance from the metacarpal to the trapezium remains the same as the distance of the implant head 120.

The use of trial head 70 in conjunction with implant stem 111 reduces the number of surgical steps successfully completed by the end user. By first checking the size using trial head 70 before selecting the implant to be used, the need for the surgeon to open and use the implant on a trial-and-error basis is avoided.

Appliance tray 80 (Figs. 22 and 23)

The advantage of the instrument tray is that instead of containing a plurality of brackets to accommodate individual tools 85, all of the tools are positioned by two strips 81, 82, which may be polymer PPSU (polyphenylsulfone), mounted (e.g., screwed) to or integrally formed with the base 83. The tool (only tool 85 shown) is further secured by a single strap 86 attached to the underside of the cover 87, which strap acts on the thumb gripping plane of the handle of the tool. The correct orientation of the cover 87 (and hence the securing strap 86) is ensured by positioning the two latches closer together on one side of the cover than the other (not shown).

Intraoperative assembly fixture 140 (FIGS. 24(a) and (b))

Assembly fixture 140 may be used in a surgical environment to assemble bushing 100 into rod 111. The base 141 of the fixation device 140 has a separate retainer 142 for each implant rod size. Each holder 142 has a socket 143 for holding the distal (narrow) end of the hanger bar 111 to hold it in an upright position. The retainer 141 also has an aligned upper through hole for retaining the wider (proximal) end of the rod 111. The dimensions of each holder increase from left to right for a particular bar size, referred to as bars A, B, C, D and E, respectively.

The assembly also includes a pusher 148 having a knurled thumbwheel 149 for rotating a screw 150 having a lower push surface 151. A screw 150 extends through the pusher body and has a pair of parallel dovetails 152 for engagement in respective dovetail slots 145.

The rod 111 is placed vertically in a suitable holder 141 and the bush 100 is aligned with a universal cap formed by the body 152 of the pusher 148, incorporating a light snap fit when it is fitted to the bush. The pushers 148 are positioned so that the center of the screws 150 is centered over the rods when fully pushed into place in either set of slots 145. The screw 150 is then turned to push the bushing 100 completely into the rod 111, thereby seating the bushing 100 in the rod 111.

List of all tools of a preferred example

The following is a list of all components of the total tool assembly apparatus in one example.

It will be appreciated that the described apparatus provides a major aid to the surgeon in terms of accuracy and reduced time to perform the procedure.

The invention is not limited to the embodiments described above, which may vary in construction and detail.