Arthroscopic shoulder arthroplasty, components, instruments, and methods of use thereof

Abstract

The present application discloses a novel method and instrumentation procedure for inserting a humeral (HC) and glenoid (GC) total shoulder implant for bone preparation and inserting a component through a small incision using arthroscopic visualization. A small instrument (24) and a hollow catheter and a reamer (64) are used to perform the operation under direct arthroscopic visualization. For ease of insertion, the components are inserted separately and assembled in situ. Fixing the humeral component in place is achieved by utilizing a bicortical screw (75) that penetrates the center pin (2a) of the component. Components, their components, and instruments used therewith are also disclosed.

Description

Field of the Invention

[0001] The present invention relates to the use of patient-specific shoulder implants, and in particular to the use of instruments and guides that allow arthroscopic insertion of components forming a shoulder prosthetic implant. The present invention also relates to shoulder prostheses and components thereof, tools and devices used with shoulder prostheses, and methods of use thereof. Background of the Invention

[0003] Shoulder replacements have been performed for decades. The articulating surfaces of the shoulder joint include the ball and socket, which can become damaged due to trauma or degenerative disease. Pain and limited motion will require replacement of the articulating surfaces using a hemispherical humeral component and a shallower glenoid component. Damage to the rotator cuff and supporting structures will require the use of a reverse shoulder implant, where the component geometry is reversed and the humeral component is designed as a cup-shaped concave, while the hemispherical ball is attached to the glenoid plate.

[0004] However, the surgical procedure for inserting the prosthetic components requires extensive surgical exposure, which can excessively disrupt local anatomical structures such as surrounding muscles and adjacent tendons. This disruption can result in a prolonged rehabilitation period and the need for extensive postoperative physical therapy. However, anatomical shoulder implants, as well as newer reverse implants, have traditionally been inserted via a conventional expandable surgical approach. Traditionally, the proximal humerus is reamed to allow for the insertion of the stem of the humeral component. However, the presence of prior trauma and proximal humeral deformity precludes the use of implants with humeral stems. Recently, stemless or pedicleless humeral components have been designed and used, but remain bulky and require insertion via a conventional extensive surgical approach. The shoulder joint is anatomically a distraction joint, in contrast to the hip, knee, and ankle joints, which are weight-bearing and compression joints. In the shoulder joint, compression forces are limited to lifting heavy objects when the arm is in a horizontal position. Conventionally used glenoid polyethylene components are known to flow and become loose, leading to osteolysis. SUMMARY OF THE INVENTION

[0006] In one aspect, the present invention relates to new methods and surgical techniques that provide improved instrumentation for arthroscopically inserting the components of the total shoulder prosthesis of the present invention, thereby minimizing damage to the surrounding muscles and supporting ligaments and tissues. In another aspect, the present invention relates to implantable shoulder prostheses, their components, and parts thereof. In yet another aspect, the present invention relates to instruments and devices for use with arthroscopically implantable shoulder prostheses and methods of using the same. Other aspects of the invention will become apparent from this patent specification and the accompanying drawings.

[0007] One aspect of the present invention is to provide a surgical method for implanting the components of the humeral component and the components of the glenoid component of the total shoulder prosthesis of the present invention using arthroscopic techniques, utilizing stab wounds and minimized surgical incisions. The minimized incisions are used to perform the initial steps of the method of the present invention. After each component has been inserted through one or more stab wounds and minimized surgical incisions, the components of the humeral component and the components of the glenoid component are assembled in vivo in the working space of the shoulder joint in the patient's body to form the assembled humeral component and glenoid component of the total shoulder prosthesis of the present invention.

[0008] According to the method of the present invention, an arthroscope is introduced from the upper side via common conventional techniques to visualize the anterior surface of the proximal humerus and the humeral head. Initially, the humeral head is transected, which will reduce the joint and provide an accessible working space within the shoulder joint. An external osteotomy (cutting) guide (instrument) device having an arm and a cutting slot with an angle of about 30°-70° inclination, preferably with an angle of about 500° inclination relative to the arm, is preferably fixed to the humerus using a pin inserted percutaneously below the surgical neck of the humerus. The osteotomy guide is aligned along the anterior surface of the arm. A saw blade, preferably a small reciprocating saw blade, advantageously having a plate blade guide component is then inserted in front through a small anterior skin incision, and the osteotomy of the head is performed through the cutting slot of the osteotomy guide. Care is taken to avoid damaging the subscapularis tendon, which is attached to the inner surface of the humerus below the surgical neck. To facilitate the removal of the head, it can be broken in the accessible working space and then removed therefrom in the form of fragments. The fragmentation may be performed under direct arthroscopic visualization using a reciprocating saw blade and / or a high speed rotating burr. These tools are preferably configured to be usable through the cutting slot component of the osteotomy guide.

[0009] The next step is to prepare the humeral head to receive the implantable humeral component. A mechanical center locator is inserted through a first small anterior skin incision, which will allow the center of the humeral cut surface to be located under the direct visual monitoring of the surgical surgeon through the arthroscope. The humeral guide device includes a mechanical center locator, which is detachably connected to one end of the outrigger, thereby allowing the outrigger to be fixed to the mechanical center locator component and separated therefrom when needed. A portion of the outrigger is configured as a guide for inserting a guide pin through a stab wound on the side of the shoulder to penetrate the lateral cortex of the humerus and allow the guide wire to pass through the cut surface of the humeral head, preferably at or near its center, and then a hollow shaft is inserted (coaxially) onto the guide wire. A small circular drilling reamer will be introduced above the guide wire, which will allow the small circular drilling reamer to make a cylindrical center groove in the humeral cut surface, which will accommodate the center nail component of the humeral component. The center pin has an appropriately threaded center hole and alignment recess for use with a locator instrument that is used to guide a drill bit and for drilling a hole through the anterior surface of the proximal humerus for use with a fixation screw for securing components of the humeral implant.

[0010] The glenoid can be prepared to provide a glenoid assembly. In a preferred embodiment of the invention, the glenoid assembly is formed of metal or a metallic material, but may be formed of other materials. The glenoid assembly includes a base plate component configured to be connected to the prepared glenoid surface. The glenoid assembly also includes a glenoid component adapted to be snapped and secured to the joint in a groove of the connected glenoid base plate, preferably via one or more locking tabs. Advantageously, the glenoid component can have a convex surface that is preferably a polished metal joint surface, or when the glenoid assembly is a reverse glenoid assembly, the glenoid component can have a concave surface, which is also preferably a polished metal joint surface.

[0011] Under direct visual inspection, the center guide wire is inserted into the center of the glenoid fossa, and the circular reamer is inserted into the center guide wire, and the articular surface of the glenoid is shaved with the reamer, so as to accept the base plate component of the glenoid assembly.Optionally but preferably, 3 hole templates are introduced into the guide wire, which will help to drill holes in the appropriate position, to accept cancellous bone screws and center nails, and then remove them. Such templates include the hole corresponding to the location of any center column and the position of any cancellous bone screws to be used in the implantation base plate component. Then, introduce the base plate component of the glenoid assembly, and utilize the cancellous bone screws with appropriate length to be fixed to the glenoid in the appropriate position. Subsequently, via a plurality of locking plates, the glenoid component is buckled and fixed in the groove of the glenoid base plate connected. In different embodiments, the glenoid component can be made of non-metallic materials, such as synthetic polymers, such as polyethylene, or can be ceramic. Can be glued with the contact surface of bone.

[0012] The metal humeral component is then introduced through the anterior incision and threaded over the compression rod tip. An alignment groove at the end of the center pin ensures that the sliding sleeve and outrigger are properly aligned for insertion of the set screw. The set screw advantageously penetrates both the anterior and posterior cortices, providing better fixation than screws or other mechanical fixation methods applied in weaker cancellous bone.

[0013] The polyethylene hemispherical head of the humeral component is then squeezed in through the anterior skin incision and snapped onto the implanted metal humeral component. The hole for the fixation screw is then drilled, measured, and tightened. The fixation screw is then inserted into place through the anterior incision.

[0014] The drawings and detailed description of the present invention are not intended to limit the present invention to the particular form disclosed, but rather the present invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present invention.

[0015] BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will be better understood by reading the following detailed description, which does not limit the general inventive concept, the method of implantation, the apparatus and non-limiting embodiments thereof, and by examining the accompanying drawings, in which:

[0017] Figure 1 A perspective view of the humeral component is shown.

[0018] Figure 1A Perspective views of the humeral component in different configurations are shown.

[0019] Figure 2 A perspective view of the (external) osteotomy guide is shown.

[0020] Figure 3 Shown is a pin fixed to the humerus under arthroscopic guidance. Figure 2 A perspective view of the components of an osteotomy guide.

[0021] Figure 4 A fluoroscopic view of the proximal humerus, entry stab wound, and fragment removal of the humeral head is shown.

[0022] Figure 5 Shown is the location of a powered circular reamer used to remove the glenoid socket following resection and removal of the humeral head.

[0023] Figure 6 Shows Figure 2 A central device at the distal end of the arm of the osteotomy guide.

[0024] Figure 7 A cross-sectional view of an implantable humeral component, including its components, is shown.

[0025] Figure 8 Another embodiment and cross-sectional view of an implantable reverse humeral component, including components thereof, is shown.

[0026] Fig. 9 A perspective top view of a small reciprocating saw blade with a plate blade guide is shown.

[0027] Fig.10 A cross-sectional view of an implantable glenoid component, including its components, is shown.

[0028] Fig.11 A cross-sectional view of an implantable reverse glenoid component and its components is shown.

[0029] Fig.12 A top cross-sectional view of the mechanical centering locator component of the humeral guide is shown.

[0030] Fig.13 Shows Fig.12A side view of the mechanical center locator components.

[0031] Fig.14 A perspective view of the humeral center locator guide attached to a removable outrigger is shown.

[0032] Fig.15 A perspective view of a small round glenoid reamer is shown.

[0033] Fig.16 A fluoroscopic drill reamer is shown for use with a humeral implant.

[0034] Fig.17 A cross-sectional view of a compression instrument is shown.

[0035] Fig.18 is a perspective view of a positioner instrument.

[0036] Fig.19 is a perspective view of the implanted humeral component and the fixation screw partially inserted into the proximal humerus.

[0037] Fig. 20 is a flow chart of the method of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0039] While the invention is susceptible to various changes and modifications, specific embodiments of the invention are shown by way of example in the drawings and will be described in detail herein.In the drawings, like reference numerals and / or letters refer to like elements in the various views.

[0040] Reference now Figure 1 and Figure 7, which shows an embodiment of an arthroscopically implantable humeral component HC, comprising a head component A that can be fixed or secured to a base component B. In the embodiment shown, the head component A comprises a protruding, generally hemispherical articular surface 5, and a base component B, a fixing portion 2, which is ideally metallic. The fixing portion 2 is generally cylindrical and comprises a central pin 2a configured to be inserted into a component of the humerus at one end, and an insertion portion 2b terminating at a substantially flat end face 1 at the other end, which is configured to be slidably inserted into a groove 6 extending inwardly from the flat surface 5a of the head component A, the head component being advantageously formed of polyethylene in this embodiment, but may be formed of any other suitable material; such materials may be alloys or ceramics. The base component B comprises an axial threaded recess 11 having a thread 3 in its interior, and a transverse groove 12 recessed into a substantially flat base 2c as an alignment recess AR, the groove 12 spanning the open end 11a of the threaded recess 11. Also visible is a cylindrical hole 10 that enters (but, as shown, preferably passes through) the perpendicular central axis of the fixing portion 2 of the component of the central nail 2a, the hole 10 being sized to receive a fixing screw after the humeral component HC is inserted and the fixing portion 2 is compressed in place in the proximal humerus. It should be noted here that the hole 10 does not necessarily need to pass completely through the tapered central nail 2a, but can end inside the central nail 2a without having to be as Figure 7 1 completely therethrough. It should also be noted that in other embodiments, two or more holes 10 may be present in the base component B. It is particularly important to observe the arrangement of any such hole 10 relative to the alignment recess AR, in this case the lateral alignment slot 12, because the particular degree of radial offset between the orientation of the alignment recess AR and the hole 10 can be used to determine the relative position of the hole 10 relative to the alignment recess AR; this can be simply done by measuring from a reference point on the alignment recess (i.e., a corner or other component) and the distance from the base 2c of the hole 10 and the radial offset from that point on the alignment recess AR. Reference Figure 1A and 1B This relative offset is subsequently used to determine the position of the humeral component in which holes are to be drilled and tapped after the base component B has been compressed and inserted into the humerus, and will be described more fully with reference to the following figures. Figure 1 and Figure 7As a non-limiting example, the radial offset between the location of the hole 10 and the location of the alignment groove 12 is 0° of arc because the central axis of the hole 10 and the central transverse axis of the alignment groove 12 are in the same plane. It should be understood that the radial offset can be any value other than 0° of arc, and in the case of multiple holes 10, there can be multiple radial offsets. It is only necessary to determine and know at least one radial offset or other relative position to the alignment groove AR (or its components) before implanting the base component B in the humerus.

[0041] In an alternative embodiment, instead of Figure 1 and Figure 7 The alignment groove 12 shown, other configurations of alignment grooves that engage with components of other instruments may be used. Such optional alignment grooves may be grooves of other forms or geometries extending from the substantially flat base 2c. For example, it may be any of substantially any configurations, and include, but are not limited to: regular geometric shapes, such as ellipses, triangles, squares, pentagons, hexagons, or one or more holes may simply be provided that extend through the base 2c but are spaced apart from the open end 11a of the threaded groove 11, such as one or more holes into which a pin may be inserted. Such grooves of other forms or geometries are only required to engage with other instruments used in the method of the present invention, and may be used to locate the position of at least one hole 10 relative to the alignment groove AR. In Figure 1A A non-limiting example of such an alternative embodiment of the humeral component HC is shown in FIG. As seen in the figure, Figure 1A and Figure 1 The embodiment of is different in the configuration of the alignment groove AR, which is a generally square alignment groove 12 a having a relatively shallow depth terminating at a flat base 12 c and having a center substantially coinciding with the center of the thread groove 11 . Figure 1A The embodiment also shows a central nail 2a having two offset holes 10a and 10b, which are radially spaced from each other by an arc of 90° and each of which enters the interior of the central nail 2a through the side wall 2k. Figure 1A As can be understood from the consideration of FIG. 1 , each of the two offset holes 10a and 10b is spaced apart from the substrate 2c by a different distance. Figure 1AIt can also be understood that each of the two offset holes 10a and 10b coincides with a different corner of the square alignment groove 12a, that is, the hole 10a coincides along the (dummy) line L1, and the hole 10b coincides along the (dummy) line L2. One or two of these corners can be used as reference points for the alignment groove AR. In this way, the relative position of the holes 10a and 10b relative to the alignment groove AR can be determined. This spatial relationship can be replaced by using other instruments (or parts thereof) with an engagement tip ET, and the engagement tip ET has a geometric structure complementary to the alignment groove AR. Therefore, when the engagement tip ET is properly inserted into the alignment groove AR, the corresponding mark L2M on the instrument I overlaps with a specific part of the alignment groove 12, here is close to the corner of the alignment groove 12 of the hole 10b whose positioning corresponds to the line L2, and when the position of the hole 10b relative to the two alignment grooves AR is known, and the length between the hole 10b and the substrate 2c is known, the hole of the implanted substrate component, that is, the position of the hole 10b, can be established using other instruments (tools) of appropriate configuration that are appropriately engaged with the alignment groove AR. exist Figure 1A In the embodiment of FIG. 2 , the holes 10a, 10b extend transversely through the substrate 2c.

[0042] Figure 1B Shows that in most aspects Figure 1 Other non-limiting examples of such alternative embodiments of similar humeral components HC are shown. As shown, Figure 1B and Figure 1 The embodiment of is different in that the alignment groove AR is configured differently, being substantially circular 12a, having a center substantially overlapping the center of the threaded groove 11, and also having an inner sidewall groove 12d sized to accommodate the splines 90c that form part of the engagement tip ET of the hollow locating sleeve 90. The depth of the alignment groove AR is relatively shallow, terminating in a flat base 12c that contacts the locating sleeve 90. Therefore, the engagement tip ET having the protruding splines 90c can only be inserted into the alignment groove AR in one way (orientation), because the splines 90c can only be inserted into the inner sidewall groove 12d so that the end of the engagement tip ET is completely located in the alignment groove and contacts the flat base 12c, thereby fully engaging with the alignment groove AR and the engagement tip ET. Therefore, this one-way orientation is an embodiment of a "keyed" engagement tip ET that engages with a suitably configured alignment groove AR, because the engagement tip ET can only be inserted into the alignment groove AR in one way. Since all the physical dimensions of the base component B are known and can be measured prior to its implantation, the distance of any hole 10 from the flat base 2c and its radial offset from the position of the inner sidewall recess 12d relative to the inserted engagement tip ET are known. Figure 1B, this relationship is illustrated by line L1, which shows that the center of the hole 10 coincides with the midpoint of the inner side wall groove 12 at the base 2c. Therefore, accordingly, any point on the positioning sleeve 90 can be established relative to the spline 90c of the component forming the engagement tip ET, which can be used to establish the position of the hole 10 relative to the said point on the positioning sleeve 90 when the alignment groove AR and the engagement tip ET are fully engaged relative to each other.

[0043] The base part B comprises locking elements for joining the base part B to the head part A. Figure 7 , the locking elements are shown as (at least) two or more deformable or bendable locking tabs 8, which extend outwardly from the side wall 2f of the insertion component 2b and are configured to interlock to an annular groove 7, which is recessed (or it may be one or more other suitable grooves) in the inner wall 6b of the head component A; this provides a "snap fit" that securely connects the base component B to the head component A to form a complete, implantable humeral component HC. Other locking elements may also be used for the humeral component HC. The center nail 2a optionally but preferably tapers slightly inwardly (i.e., toward its central axis), preferably at a taper angle of approximately 0.5° to 10°, preferably 2° to 5° of arc, to better retain it in the humerus. As shown in Figure 7 As can be clearly seen above, a disc 9 (optionally referred to as a flange 9) extends radially outward from the base member B and is located between the insertion member 2b and the center nail 2a. The disc 9 is provided to reduce the flow of polyethylene under load and prevent the components of the fixing part 2 from further penetrating into the head member A, especially into its polyethylene.

[0044] In other Figure 1 and Figure 7 In different embodiments of the embodiment shown, in Figure 8 In this embodiment, which is optionally referred to as a "reverse humeral component", a head component A has a Figure 1 , Figure 7 Here, the head component A comprises a concave substantially hemispherical head 14, that is, it has a cavity or cup 14a, which has a concave articulating polyethylene surface 5, which is configured to interface with the concave hemispherical glenoid articulating surface, as in Fig.11 As can be seen above, the figure shows a corresponding glenoid component GC which is optionally referred to as a "reverse glenoid component" because it provides an interfacial contact surface with a complementary, Figure 8 The cavity or cup-shaped concave concave 14a is concave on the hemispherical joint polyethylene surface 5.

[0045] As previously stated, an object of the present invention is to provide a method for inserting and implanting the humeral component and glenoid component of a total shoulder prosthesis using an arthroscopic technique that requires only a minimal puncture wound and significantly reduces skin incisions and surgical damage to tendon structures such as the subscapularis.

[0046] Reference now Figure 2-6 and Fig. 9 To achieve this objective, according to the method, the humeral head 36 in contact with the glenoid surface 37 is first removed using an osteotomy guide 27 removably secured to the anterior surface of the arm. The osteotomy guide OG (e.g., osteotomy guide 27) is secured to the humerus H in the humeral H region proximal to the humeral head 36 using a pin 3, which is inserted through a small stab wound into the skin of the arm AM and whose position is visually controlled by the surgeon using an arthroscopic camera 41 attached to an arthroscope 43 introduced anteriorly and superiorly through the stab wound 70. The centering device 28 at the distal end of the arm 27b will ensure that it is centered over the bone landmarks of the elbow including the medial 29 and lateral 31 epicondylar protrusions. The distal end 27a of the osteotomy guide 27 is aligned on the anterior surface of the arm, wherein the medial and lateral expandable supports 29 and 31 of the centering device 28 will ensure that the osteotomy guide 27 is centered relative to the humerus H. As seen from Figure 6 As can be best seen in the figures, components of each of the laterally expandable brackets 29 and 31 of the central device 28 include a rack, 29a and 31a respectively, which engages with a central gear 30, whereby movement of any one of the laterally expandable brackets 29 and 31 is converted into similar movement of the other of the laterally expandable brackets 29 and 31 via the central gear 30. Located distally from the racks 29a and 31a, each of the laterally expandable brackets 29 and 31 includes an angled end member, 29b and 31b respectively, which is configured to include components of the arm AM therebetween. Optionally but advantageously, the arm 27b is formed by two sliding or telescopic components 27b, which allows the overall length of the arm 27b to be varied. In the event that the two sliding or telescopic components 27b include the arm 27b, there may also be a locking means such as a locking screw 35 (or other device or component) to allow the two sliding or telescopic components 27b to be temporarily fixed relative to each other. As can be seen from Figure 2 It can also be seen that the proximal end of the arm 27b comprises a support member 34 on which is fixed a cutting guide 33 having a transverse slot 32 with an angle of about 30°-70°, preferably about 50°, relative to the centerline of the arm 27b. Figure 2It can also be seen that the centering device 28 is located at or near the distal end of the arm 27b. In a preferred embodiment, the centering device 28 can be repositioned on the arm 27b, and particularly preferably can be rotated about the arm 27b so that it can be placed on the opposite side; this can "reverse" or "flip" the osteotomy guide 27 so that it can be used on the patient's opposite shoulder joint. Returning to the method, a first small incision 39 is made in the front and the guide slot 32 is cut to be inserted as shown. Fig. 9 A small reciprocating saw blade is shown introduced into the joint, the saw blade 24 having a saw portion 24 having teeth 24b on one side, a blade handle 24c extending to a guide plate 25, the opposite end of which extends an attachment handle 24d terminating in an attachment 26 suitable for attachment to a reciprocating conventional power drive. The guide plate 25 and saw portion 24 can be inserted into the slot 32, and the guide plate 25 will stabilize and ensure that the saw blade 24 always remains in the cutting plane defined by and parallel to the slot 32. The surgeon may encounter difficulty in removing the humeral head due to deformity or size. Subsequently, the guide 27 is removed and the humeral head is cut into several pieces or segments using a reciprocating saw introduced through the first incision 39, thereby achieving segmented extraction. Smaller resected fragments 69 can be removed through the first incision 39.

[0047] The next step is to prepare the glenoid articular surface; see Figure 5 and Fig.15 To improve visualization of the glenoid cavity, the humerus H can be pulled downward (in the direction of arrow "x") and rotated outward to increase the working space J in the shoulder joint. A guide wire 44 is inserted into the glenoid surface 37 under direct arthroscopic 41 visualization. A small circular reamer 45 attached to a rotary power unit 42 is then powered, causing the reamer 45 to rotate and be used to flatten the surface, Fig.15 , preferably for providing a substantially flat surface into which the implantable glenoid component GC may be mounted (implanted). This operation may be repeated one or more times; the guide wire 44 may be inserted into different portions of the glenoid surface 37, and the surface prepared as described above in the different additional surface portions, until a suitable surface is available to receive the glenoid floor component D. Once the glenoid surface is appropriately prepared, a conventional drill guide (not shown) is inserted through the first skin incision 39, and a long drill bit attached to the external rotary power tool 42 is used to make the borehole.

[0048] Reference now Fig.10 , Fig.11, which shows two embodiments of an implantable glenoid component GC, each of which includes a glenoid component C that can be fixed or secured to a glenoid base plate component D. Now returning to the method, the glenoid base plate 15 is then inserted through the incision 39 and, after drilling and tapping, secured to the prepared glenoid surface using two (or one, or more than two) cancellous bone screws 19 under direct arthroscopic visualization. Optionally but preferably, the base plate component D includes a central post 18 extending outwardly from the lower surface 15a, which the base plate 15 will stabilize during screw insertion. The screws are inserted through appropriately sized and placed screw holes 15b, which are preferably chamfered to ensure that the head 19a of the cancellous bone screw 19 coincides with or is below the substantially flat base surface 16f in the cavity 17. The size of the cavity 17 is such that a portion of the base 16e of the glenoid component C can be received and retained therein. Moreover, although in Fig.10 , Fig.11 Not shown, but the floor member 15 is substantially circular when viewed perpendicularly to the central column 18 which, if present, advantageously coincides with the central axis of the floor member 15 .

[0049] The glenoid component C is then inserted through the skin incision 39 and securely snapped into the cavity 17 and secured by one or more locking tabs 16a extending from the base sidewall 16b of the base component 15. When the base 16e of the corresponding glenoid component 20 or 23 is located within the receiving cavity 17, the locking tabs 16a engage with one or more appropriately sized locking recesses 16 in the inner sidewall 16c of the base component 15. It should be understood that Fig.10 The embodiment of the present invention shows a glenoid base component 15 and a glenoid component 20, the latter having a concave (or cup-shaped concave) articulating surface GS (or cup-shaped concave) which is suitable for being combined with a joint body having a structure including Figure 1 The articulation surface GS interfaces with the humeral component HC of the head component A of the convex substantially hemispherical articulation surface 5 shown in FIG. Advantageously, the articulation surface GS is a polished metal articulation surface, but may be a polymer surface (ie polyethylene), an alloy or a ceramic surface. Fig.11 A different embodiment of the invention is shown in which the glenoid joint component 23 has a "reverse" design and has a convex hemispherical geometry and a convex articulation surface GS; this is in contrast to the hemispherical head component A of the humeral component HC (see Figure 8 ) in combination, which has a corresponding reverse geometry, that is, it has a cavity or cup 14a comprising a concave articular surface 5. Advantageously, the articular surface GS is a polished metal articular surface. Nevertheless, Fig.10 glenoid implant components or Fig.11 The method of arthroscopic insertion of the reverse glenoid implant component remains the same.

[0050] The next step is to prepare the cut surface of the humerus for insertion of the humeral component. Fig.12 , Fig.13 , Fig.14 , Fig.16 , Fig.17 , Fig.18 The mechanical centering component 54 of the guide instrument (GI) is introduced through the anterior incision 39 and placed on the cut flat surface 40 of the humerus H. The surgeon directly checks the position of the device through the arthroscope inserted upward through the stab wound 70. The claws 47 and 50 are squeezed apart using surgical forceps (not shown), wherein the two small grooves 51 and 52 are squeezed. Fig.12 As can be seen, the components of each of the jaws 47 and 50 include a rack portion, 47a and 50a respectively, which engages with the central gear 49, whereby the movement of either jaw 47 or 50 is transferred to a similar movement of the other jaw 47 or 50 via the central gear 49. Once the forceps are released, the jaws 47 and 50 will be closed by the spring 48, which pushes the jaws 47, 50 in the direction of the central gear 49, thereby firmly holding the mechanical centering member 54 on the cut surface 40 of the humerus H. Since the lengths of the jaws 47 and 50 are preferably the same, the mechanical centering member 54 provides a self-centering function relative to the cut flat surface 40 of the humerus H. The outrigger 61 is then attached to the mechanical centering member 54 via its proximal end through the upper incision 70 and inserted into the connecting channel 55. As can be seen, preferably, the cross-section of the connecting channel 55 is non-circular, here it is square, because the non-circular cross-section helps to firmly fix the outrigger 61 and limit its rotation relative to the mechanical centering member 54. The outrigger 61 will facilitate accurate insertion of the central guide wire 58 via the perforated guide 59 at the contralateral distal end 61b of the outrigger 61, which will also be used to insert the tapered humeral hole reamer 64 and will also facilitate accurate drilling of a groove in the humeral component to correspond to the hole 10 (see Fig.17 ), and tap the proximal humerus H for inserting the fixing screw 75. Insert the hollow handle 62 (or other hollow handle 62) into the guide wire (see Fig.16 ) and removed from the central part of the humeral cutting surface 40. The hollow shaft 62 has threads at its proximal tip; a circular drilling reamer 64 having a central threaded portion is introduced through the main incision 39 and the threaded tip of the hollow handle 62 is screwed (see Fig.16). The distal end of the hollow handle 62 is operably attached to the rotation power unit 42, which rotates the humeral reamer (which preferably tapers inwardly) and cuts into the central portion of the humeral cutting surface 40 under arthroscopic observation until a central recess BR of an appropriate size is drilled into the humerus H for receiving the nail 2a of the base component B. Subsequently, the base component B is introduced through the first incision 39, wherein the central nail 2a is inserted into the drilled central recess BR.

[0051] In order to achieve the compression of the base part 2 into the drilled central recess BR, a compression device 67 (CI) is used (see Fig.17 ). The compression instrument CI has a slidable handle 68a, which has threads at its opposite end at least partially within a hollow (or hollow) sleeve body 62. The sleeve body 62 has a shoulder 62a at its proximal end and 62b at its distal end. The proximal end of the compression instrument 67 is introduced through the side puncture 63 and supports the shoulder 62a adjacent to the passage P through the humerus, and the handle 68a extends through the passage P until a set of threads 68b at the proximal end of the handle 68a is screwed to the handle 68a in the threaded groove 11 of the center nail 2a. With the shoulder 62a adjacent to the lateral cortex of the humerus, rotation of the knob 68 causes the handle 68a to move distally (i.e., away from the joint) and draws and compresses the center nail 2a into the groove BR of the drilled hole of the humerus H. Therefore, the base component B is placed in the groove BR of the drilled hole under the compression provided by the rod 68b. The central pin 2a is placed until the disk 9 is aligned with or rests on the cut flat surface 40 of the humerus H. The compression instrument 67 can be removed, (or alternatively only the sleeve body 62 and knob 68 can be removed, as in some embodiments, the rod 68a can be used to form part of the positioning instrument (LI).

[0052] The locking set screw 75 is then inserted (see Fig.19 ) The proximal humerus needs to be precisely drilled and tapped in order to engage the screw 75 in the hole 10 of the implanted central nail 2a. To achieve this purpose, the positioning instrument LI includes at least one hollow positioning sleeve 90, which has a proximal part 90a, which has an engagement tip ET at its proximal end 90b, here a pair of alignment plates 72, which have a geometric structure complementary to the alignment recess AR of the base part B, here the alignment groove 12 in the central nail 2a. The diameter of the passage P through the humerus H is sufficient to allow the insertion of the proximal end 90b and the alignment plates 72 extending outward therein, so as to mechanically engage and position the positioning sleeve 90 relative to all elements of the implanted central nail 2a and the base part B, in particular any hole 10. (Here, and with reference to Figure 1A , where the configuration of the bonding tip ET is Fig.18Unlike the one shown, a passage P having a smaller diameter or size may be sufficient to allow insertion of such an engagement tip ET with an alignment groove AR having a suitable complementary geometry and to allow proper positioning of the hole 10 in a manner similar to that described herein.) The hollow positioning sleeve 90 also includes its distal portion 90b, preferably in conjunction with a proximal portion 90a. Although the proximal portion 90a advantageously has a hollow circular cross-section, the distal portion 90b advantageously has a hollow non-circular cross-section, i.e., a square, pentagonal or hexagonal cross-section, although a circular cross-section may also be used, but may be less suitable. From the foregoing and from Fig.18 As can be appreciated from the accompanying drawings of the embodiment of the present invention, the two portions of the hollow locating sleeve 90 have a length dimension that can be determined from the engagement tip ET to any position or point on the hollow locating sleeve 90, so that when the engagement tip ET (here, the alignment tab 72) is engaged into the alignment recess AR (here, the alignment slot 12), any point or hole 10 in the correspondingly implanted central nail 2a can be established as a distance from any position or point on the hollow locating sleeve 90. This spatial relationship is used to locate one or more such holes 10 using other components of the positioning instrument LI, namely the locator outrigger 66. When the engagement tip ET is located in the alignment recess AR, this can be facilitated by an indexed mounting rod 98, which can be removably fixed to a component of the distal component 90b, the mounting rod 98 having a threaded proximal end 96 that engages the axial threaded recess 11 and having one or more indexing index marks 84 at or near its distal end. Since the locator outrigger 66 is preferably rigid, its length from the locator hole 99 in its proximal arm end 66a to the distal clamp arm end 66b is constant so that the position of the locator hole 99 can be overlaid on the position of the hole 10 in the implanted central nail 2a by appropriately placing the locator outrigger 66 relative to the locating sleeve 90. The position of the locator outrigger 66 can be established by fixing it in position on the locating sleeve 90 by any suitable means, and its position can be changed. Fig.18The illustrated embodiment shows a preferred embodiment in which the configuration of the distal clamp arm tip 66b has a cross-section that is complementary to the cross-sectional shape of the distal member 90b, thereby forming a non-circular cross-section, i.e., a triangular, square, pentagonal or hexagonal cross-section, which in itself advantageously provides good rotational stability of the locator outrigger 66 and the engaged locator sleeve 90, which is preferably positioned so that its tip 61 coincides with the indexing indicator 84, which ensures that the engagement tip ET is located within the alignment groove AR. The locator outrigger 66 can then be mounted relative to (or indexed relative to) one or more hole reference positions, such as by using a knurled screw 66c, the tip of which can be pointed at a location (i.e., 92, 92a, 92b) known to provide appropriate placement of the locator hole 99 on the hole 10 of the implanted central nail 2a, and is received by the locating groove 92 (and / or 92a, 92b) located on the distal member 92b of the locator sleeve 90. Such a locating groove 92 represents a non-limiting example of a "hole reference position" location, which may be different in different embodiments, i.e., it may be a line or mark present on a component of the locating sleeve 90 that is used to align the two parts. Thereafter, a conventional surgical drill bit may be inserted through the locator hole 99 and used to drill a hole through the humerus H, which will coincide with the hole 10. To avoid damaging the soft tissue, after the locator outrigger 66 is positioned over the hole, an additional small incision is made and a hollow guide sleeve (not shown) is inserted through the additional small incision to isolate the surrounding soft tissue and allow the guide sleeve to be inserted into or adjacent to the locator hole 99. Then, a drill bit and / or tap of appropriate size is inserted through the guide sleeve and used to drill and / or tap the humerus H; thereby isolating the cutting edge of the drill bit and / or tap from the surrounding soft tissue. Subsequently, the locator instrument LI or its components, such as the locator outrigger 66, may be removed before or after tapping the drill hole and inserting the set screw 75 which will engage at least a portion of the hole 10. The set screw 75 is inserted and threaded through the cortex of the humerus H, thereby fixing the central nail 2a relative to the humerus H. The head component A of the humeral component HC is then pressed into the shoulder joint through the main incision 39 and is fastened and locked to the base component B of the humeral component B, which is preferably metal. 2. See Fig.19 After component insertion is complete, the passage P made in the lateral surface of the humerus is plugged with bone graft. Any remaining instruments or components may then be removed and all wounds appropriately sutured or otherwise closed.

[0053] It should be understood that each component of the humeral component and each component of the glenoid component can have different sizes and dimensions, and during implantation, it may be advantageous to have multiple different sizes of each component available so that test fittings can be performed during the implantation surgery. Therefore, a kit including two or more components for forming a humeral component or a glenoid component, the components having different sizes or dimensions, can be provided and is also considered an aspect of the present invention.

[0054] Fig. 20 is a flow chart of method steps according to one aspect of the present invention.

[0055] In another aspect of the present invention, a kit of component parts that can be assembled into an appropriately sized implantable humeral component HC is provided, the kit comprising at least one, but preferably a plurality of individual head components A, which may have at least hemispherical head components A of the same size, but preferably have different sizes or configurations, and optionally but preferably also comprising at least one base component B adapted to be fixed to one or more hemispherical head components A contained in the kit. The kit may be provided in one or more sterile or serializable seals, trays or containers containing the above components.

[0056] In yet another aspect of the present invention, a kit of component parts that can be assembled into an appropriately sized implantable glenoid component GC is provided, the kit comprising at least one, but preferably a plurality of individual glenoid components C, which may have the same size, but preferably have at least glenoid components C of different sizes or configurations, and optionally but preferably also comprising at least one glenoid floor component D adapted to be secured to one or more glenoid components C contained in the kit. The kit may be provided in one or more sterile or serializable seals, trays or containers containing the above components.

[0057] In another aspect of the invention, a kit is provided, comprising:

[0058] (a) component parts that can be assembled into an appropriately sized implantable humeral component HC, the kit comprising at least one, but preferably a plurality of separate head components A, which may have at least hemispherical head components A of the same size, but preferably have different sizes or configurations, and optionally but preferably also at least one base component B suitable for fixation to one or more hemispherical head components A contained in the kit; and

[0059] (b) component parts that can be assembled into an appropriately sized implantable glenoid component GC, the kit comprising at least one, but preferably a plurality of individual glenoid components C, which may have the same size, but preferably have at least glenoid components C of different sizes or configurations, and optionally but preferably also comprising at least one glenoid floor component D adapted to be secured to one or more glenoid components C contained in the kit. The kit may be provided in one or more sterile or serializable seals, trays or containers containing the above components.

[0060] In yet another embodiment, a kit is provided that includes components of a compression instrument CI and / or an introduction instrument GI. The kit may be provided in one or more sterile or serializable seals, trays or containers containing the aforementioned items.

[0061] In yet another embodiment, a kit is provided, which includes a compression device CI and / or components of a compression device CI. The kit may be provided in one or more sterile or serializable seals, trays or containers containing the aforementioned items.

[0062] In yet another embodiment, a kit is provided that includes the locator apparatus LI and / or components of the locator apparatus LI. The kit may be provided in one or more sterile or serializable seals, trays or containers containing the aforementioned items.

[0063] In yet another embodiment, a kit is provided that includes one or more components that can be assembled into an appropriately sized implantable humeral component HC and / or one or more component parts that can be used to assemble into an appropriately sized implantable glenoid component GC. Optionally, the kit can be provided with a compression device CI, and / or parts of a compression device CI. Optionally, the kit can be provided with a locator device LI and / or parts of a locator device LI. The kit can be provided in one or more sterile or serializable seals, trays or containers containing the aforementioned items.

[0064] Yet another embodiment of the present invention is a system for (preferably arthroscopically) resecting the humeral head and glenoid socket of a shoulder joint and replacing them with a total shoulder prosthesis, the system comprising:

[0065] An implantable humeral component HC comprising a head member A fixable or affixed to a base member B;

[0066] implantable glenoid components GC, each of which includes a glenoid component C fixable or secured to a glenoid base plate component D;

[0067] Optionally but preferably at least one of the following:

[0068] Osteotomy Guide OG;

[0069] Guided instrument GI;

[0070] Compression device CI;

[0071] Positioning device LI,

[0072] One or more reciprocating small saw blades; and

[0073] One or more drill reamers.

[0074] In a preferred embodiment, the above system necessarily includes at least one of the following: osteotomy guide OG; guide instrument GI; compression instrument CI; locator instrument LI, but in certain preferred embodiments, it includes at least two, more preferably at least all 3, and particularly preferably all four of the above items.

Claims

1. A component system configured to remove the humeral head and glenoid socket of a shoulder joint and replace it with a total shoulder prosthesis, the system comprising: An implantable humeral component comprising a head member securable or fixed to a base member, a central pin having a base, an axial threaded recess extending inwardly from the base, and an alignment recess extending inwardly from the base, the alignment recess having a geometry complementary to that of an engagement tip of an instrument insertable through a portion of the humerus to allow the alignment recess to engage the engagement tip of the inserted instrument; An implantable glenoid component comprising a glenoid component that is securable to or secured to a glenoid baseplate component; Optionally at least one of the following: osteotomy guide; Guidance equipment; Compression devices; Positioning equipment, One or more reciprocating small saw blades; and One or more drill reamers.

2. The system of claim 1, wherein the humeral component further comprises a head having an articulation bearing surface and a central recess, the articulation bearing surface having a flat back surface, and the central recess being configured to receive and retain an insertion portion of the fixation portion therein.

3. The system of claim 2, wherein the base component of the humeral component includes a fixation portion having an insertion portion configured to be received within the central recess, and at least one transverse hole in the central nail for receiving a locking fixation screw.

4. The system of claim 3, wherein the base member of the humeral component includes a disk extending radially outward from the base member and positioned between the insertion portion and the central pin.

5. The system of claim 1, wherein the floor of the glenoid component comprises a generally flat glenoid floor and a cavity configured to receive and retain therein a base of the glenoid component.

6. The system of claim 1, comprising an introduction instrument including a central positioning member having compressible jaws, a connecting channel, and a removable outrigger.

7. The system of claim 1 , comprising an osteotomy guide having a central device at the distal end of an arm, and a bracket component at the proximal end of the arm on which a cutting guide is fixed, the central device having a laterally expandable bracket, the cutting guide having a transverse slot with an inclination of 30°-70° relative to the centerline of the arm.

8. The system of claim 1 , comprising a compression instrument having a slidable rod having threads at opposite ends thereof, a sleeve body having a distal end and a shoulder at a proximal end, and a knob, wherein the rod is insertable into the sleeve body, the threads at one end thereof being configured to engage with an axial threaded groove of a base component of a humeral component implanted in a humeral bone, and the threads at an opposite end thereof being configured to engage with the knob, and wherein rotation of the knob pushes the shoulder against a component of the humeral bone and causes the base component to move into a central groove present in the humeral bone.

9. A system as described in claim 1, which includes a positioning instrument, which has: a hollow positioning sleeve having a proximal part and a distal part thereof combined with the proximal part, and a locator outrigger that is detachably fixed to a portion of the distal part, the proximal part having an engagement tip at its proximal end, which has a morphology complementary to the morphology of the alignment groove of the base part, and the locator outrigger having a locator hole that covers the position of the hole of the base part implanted in the humerus when the locator outrigger is installed relative to the hole reference position present on the positioning sleeve.

10. An implantable humeral component comprising a head component securable to or secured to a base component, a central pin having a base, an axial threaded recess extending inwardly from the base, and an alignment recess extending inwardly from the base, the alignment recess having a geometry complementary to the geometry of an engagement tip of an instrument insertable through a portion of the humerus to allow the alignment recess to engage the engagement tip of the inserted instrument.

11. The implantable humeral component of claim 10, further comprising a head having an articulation bearing surface having a flat back surface and a central recess configured to receive and retain therein an insertion portion of the fixation portion.

12. The implantable humeral component of claim 11, further comprising at least one transverse hole in the central pin for receiving a locking set screw.

13. A total shoulder prosthesis comprising: An implantable humeral component comprising a head member securable or fixed to a base member, a central pin having a base, an axial threaded recess extending inwardly from the base, and an alignment recess extending inwardly from the base, the alignment recess having a geometry complementary to that of an engagement tip of an instrument insertable through a portion of the humerus to allow the alignment recess to engage the engagement tip of the inserted instrument; and An implantable glenoid component includes a glenoid component that is securable or fixed to a glenoid base plate component.

14. The total shoulder prosthesis of claim 13, wherein the humeral component further comprises a head having an articulation bearing surface having a flat back surface and a central recess configured to receive and retain therein an insertion portion of the fixation portion.

15. The total shoulder prosthesis of claim 14, wherein the base member of the humeral component includes a fixation portion having an insert portion configured to be received within the central recess and at least one transverse hole in the central pin for receiving a locking fixation screw.

16. The total shoulder prosthesis of claim 14 or 15, wherein the base member of the humeral component includes a disk extending radially outwardly from the base member and located between the insertion portion and the central pin.

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