The present invention relates to a method and apparatus for implanting a prosthesis at the intersection of two or more bone, and in particular, to a method and apparatus for processing and implanting a resected portion of a humerus to act as an articular surface for an interpositional implant of a shoulder prosthesis.
In the field of total shoulder prostheses, prostheses are commonly said to be inverted when they comprise a glenoid component that is integral with the glenoid surface of a scapula of a patient's shoulder and that delimits a convex articular surface and a humeral component that is integral with the humerus of the patient's shoulder and that delimits a concave articular surface. The cooperation of the articular surfaces of the glenoid and humeral components allow an articulated connection to be reproduced at the shoulder. However, it is common with this type of prosthesis that during adductive movement of the shoulder, the lower portion of the humeral prosthetic component strikes the pillar of the scapula, i.e. the lower portion of the glenoid located just below the glenoid prosthetic component (when the patient is standing upright). This interference between the humeral prosthetic component and the scapula limits the range of adductive movement of the shoulder and may cause pain to the patient or even lead to the prosthesis becoming dislodged due to, for example, osteolysis of the scapula.
Another method used to replace damaged shoulder joints is interpositional arthroplasty. The method of interpositional arthroplasty uses tissue from the patient or an artificial replacement to repair a damaged or malformed joint. An interpositional implant is positioned at the joint to act as an engagement surface between two adjacent bone structures to allow articular movement. In the particular field of interpositional shoulder arthroplasty, the humeral metaphysis is typically impacted to form an engagement surface for an interpositional implant positioned between a glenoid component (or glenoid) and a humeral component (or humeral metaphysis). However, if the cancellous bone in the humeral metaphysis is of poor or degraded quality, the cancellous bone may lead to gradual subsidence of the interpositional implant within the humeral metaphysis. It is thus desirable to develop an interpositional implant with a metaphyseal articular surface that will provide support and protection to the metaphyseal cancellous bone.
Some embodiments relate to a method of forming a shoulder prosthesis, including forming a concave articular surface into an end portion of a humerus, including compacting bone of the end portion to define the concave articular surface. An implant having a convex articular surface is secured to a glenoid. The concave articular surface of the humerus is articulated with the convex articular surface of the implant.
Other embodiments relate to a method of forming a shoulder prosthesis, including resecting an end portion of a humerus to form a resected end of the humerus and a resected portion separated from the humerus, the resected portion having an outer convex surface and an inner surface. The inner surface of the resected portion is processed to comprise a concave articular surface. The outer convex surface of the resected portion is implanted in the resected end of the humerus. An implant having a convex articular surface is secured to a glenoid. The concave articular surface of the resected portion is articulated with the convex articular surface of the implant.
Still other embodiments relate to a method of forming a shoulder prosthesis, including forming a recess in an end portion of a humerus and disposing a reinforcing structure across at least a portion of the recess to form a concave articular surface of the humerus. The reinforcing structure is attached to the humerus. An implant having a convex articular surface is secured to a glenoid. The concave articular surface of the resected portion is articulated directly with the convex articular surface of the implant.
While multiple embodiments are disclosed, still other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive.
In the illustrated embodiment, the glenoid component 12 includes an articular member 18 with a generally concave articular surface 20 that engages the interpositional implant 16. Given that the articular member 18 is positioned immediately adjacent the glenoid G, the interpositional implant 16 is remote from the resected surface of the glenoid G in the sense that, if the articular member 18 were omitted, the interpositional implant 16 would be directly juxtaposed with the glenoid G. Thus, on account of the articular member 18, the interpositional implant 16 and the humeral component 14 are laterally remote from the glenoid G, limiting the risk of the humerus H interfering with the bottom of the glenoid G, i.e. with the pillar P of the scapula S. Alternatively, an articular member 18 may not be required within the glenoid G. In this case, the interpositional implant 16 would articulate directly with the glenoid G.
The humeral component 14 includes an articular member 24 formed from a resected portion 30 (shown in
Alternatively, the resected portion 30 can be formed from a single piece or a plurality of pieces taken from the proximal humerus PH or other locations in the patient's body. Implantation of the resected portion 30 can be supplemented with bone graft material, such as for example a purée of bone substance, bone replacements, bone fillers, bone cements and/or bone adhesives, or a combination thereof. The bone graft material can be formed from the patient's bone, an allograft, a xenograft, or a combination thereof. Various bone replacements, bone fillers, bone cements and bone adhesives are disclosed in U.S. Pat. No. 6,692,563 (Zimmerman), which is hereby incorporated by reference. Various additives can also be included with the resected portion, including, but not limited to bone growth agents and pain inhibitors.
As will be discussed further below, the resected portion 30 is prepared and impacted into the proximal humerus PH to form the articular member 24 having a concave articular surface 32. The preparation of the resected portion 30 can be performed ex vivo or in situ.
In the illustrated embodiment, the humeral component 14 includes an optional stem 22 located in the medullary cavity M of the humerus H. The proximal end 28 of the stem 22 supports the resected portion 30 and optionally serves as an attachment member. For example, a fastener 26 can optionally extend through the resected portion 30 and engage the stem 22. It will be appreciated that the stem 22 may be omitted entirely without departing from the intended scope of the present invention.
The interpositional implant 16 is positioned between the articular member 18 of the glenoid component 12 and the articular member 24 of the humeral component 14. The radius of the interpositional implant 16 is typically equal to or less than the radii of the concave surfaces 20 and 32 of the articular member 18 of the glenoid component 12 and the articular member 24 of the humeral component 14, respectively. When the interpositional implant 16 is positioned between the glenoid component 12 and the humeral component 14, as shown in
In an alternate embodiment illustrated in
The cutting guide 34 includes a bell-shaped body 36 secured to a shaft 38. An interior surface of the body 36 has a concave surface from which the main center of curvature pertains substantially to an axis 40 from which the shaft 38 extends from the body 36. The body 36 is designed to cover the upper portion of the proximal humerus PH in the manner of a cap and is perforated to give the surgeon a better view of the proximal humerus PH when positioning the body 36. The body 36 is thus shaped to reproduce approximately the surface features of the upper proximal humerus PH of a normal anatomical humerus H. However, in practice, there will be a range of a plurality of homothetic guiding instruments 34 having bodies 36 which have respective dimensions associated with the size and the state of the patient's bones.
The shaft 38 of the cutting guide 34 is optionally provided with a protruding tube 42 centered on the axis 40 and the main center of curvature of the body 36. Once the body 36 is properly positioned over the proximal humerus PH, a guide pin 44 having a pointed distal end is introduced into the protruding tube 42 and inserted into the proximal humerus PH. The guide pin 44 preferably terminates before the cutting plane C-C′. The surgeon uses the distal surface 27 on the body 36 located in the cutting plane C-C′ to resect the portion 30 from the proximal humerus PH. Alternatively, the surgeon can cut free-hand without a template.
In another embodiment, the resected portion 30 is prepared ex vivo by removing the cancellous bone 52 from the cortical bone 56. As a result, the inner convex surface 32 is essentially the inner surface 54 of the cortical bone 56. Either of these procedures can also be performed in situ. That is, after the resected portion 30 is engaged with the proximal humerus PH.
In some embodiments, the cut surface 66 of the proximal humerus PH is prepared to receive the resected portion 30. A hemispherical reaming instrument 64, shown in
In another embodiment, the cut surface 66 (shown in dashed lines) is compacted or carved to form the concave surface 60 on the proximal humerus PH. Preparing the cut surface 66 of the proximal humerus PH may be performed using a variety of other techniques known in the art without departing from the intended scope of the present invention. Small holes may optionally be drilled through the concave surface 60 to enhance bone integration remodeling once the resected portion 30 is reversed and implanted in the humerus H.
In an alternate embodiment illustrated in
In one embodiment, a suture material 84 is optionally attached to one or more of the pins 80. The suture material 84 extends through the proximal humerus PH to the opposite side and is anchored to the cortical bone 86 using conventional techniques. The suture material 84 operates as a tension member to retain the resected portion 30 to the concave surface 60 of the proximal humerus PH.
In an alternate embodiment illustrated in
In one embodiment, a reinforcing structure 92, such as for example reinforcing fibers, a three-dimensional porous matrix or scaffold, is located between the concave surface 60 on the proximal humerus PH and the resected portion 30. In the illustrated embodiment, the reinforcing structure 92 is attached to the cortical bone 86 of the proximal humerus PH by the sutures 90. In one embodiment, the reinforcing structure 92 operates like a sling to limit further penetration of the resected portion 30 into the proximal humerus PH. In another embodiment, the reinforcing structure 92 promotes in-growth between the proximal humerus PH and the resected portion 30. Examples of such reinforcing structures include a porous matrix, a scaffold, a reticulated bioceramic framework, a structured porous tantalum and a synthetic fiber mesh. Various porous matrices and scaffoldings are disclosed in U.S. Patent Nos. 4,479,271; 6,511,511; 6,605,117; 6,797,006; 6,902,584; and 7,250,550, which are hereby incorporated by reference. Although the reinforcing structure 92 is discussed as being used in conjunction with the resected portion 30, the reinforcing structure 92 may alternatively be used in place of the resected portion 30 as an articular surface for engaging the interpositional implant 16 (shown in
In another embodiment, the reinforcing structure 92 extends beyond the sutures 90. The reinforcing structure 92 may be made of any material, natural and synthetic, suitable for implantation. Preferably the reinforcing structure 92 is flexible to permit conformity with the proximal humerus PH. The reinforcing structure 92 material may also permit intraoperative cutting or other shaping of the reinforcing structure 92 to fit a surgical site. For example the reinforcing structure 92 may be intraoperatively shapeable by cutting with scissors. The reinforcing structure 92 may include natural tissues including fibrocartilage, fascia, pericardium, and/or other natural tissues. The reinforcing structure 92 may include synthetic materials including metals, polymers, ceramics, hydrogels and/or other suitable materials. A polymer reinforcing structure 92 may include resorbable and/or non-resorbable polymers. Examples of resorbable polymers include polylactic acid polymers, polyglycolic acid polymers, and/or other suitable resorbable polymers. Examples of non-resorbable polymers include polyolefins, polyesters, polyimides, polyamides, polyacrylates, polyketones, and/or other suitable non-resorbable polymers. A metal reinforcing structure 92 may include titanium, tantalum, stainless steel, and/or other suitable metals and alloys thereof. For example metal fibers may be woven into a porous flexible reinforcing structure 92.
The reinforcing structure 92 may be attached to the hard and/or soft tissues of the proximal humerus PH by mechanical fasteners 94, adhesives, tissue in-growth, and/or other suitable attachment mechanism. The attachment mechanism may be permanent and/or bioabsorbable. For example, the reinforcing structure 92 may be screwed, pinned, sutured, or stapled to the bone and/or soft tissue adjacent the joint. The reinforcing structure 92 may include preformed openings for receiving fasteners. The reinforcing structure 92 may include a reinforced edge to strengthen the reinforcing structure 92 against pullout of fasteners. For example, the edge may be reinforced by hemming, molding, braiding, embedding a cord, and/or by other suitable reinforcement mechanism. The reinforced edge may form a thicker portion of the reinforcing structure 92.
As previously mentioned, the method of resecting natural bone and compacting the resected surface of the natural bone with the resected portion to form a concave articular surface for engagement with a convex articular surface of an interpositional implant to repair or replace a damaged joint is not limited to repairing or replacing a damaged shoulder.
In another embodiment, the proximal end 130 of the proximal phalange 114 is resected and processed as discussed herein. The naturally convex surface 132 of the metacarpal 134 engages directly with the concave articular surface 136, without the need for an interpositional implant.
As can be seen in
Similar to the interpositional implants 100, 106 and 112 depicted in
Various modifications and additions can be made to the exemplary embodiments discussed without departing from the scope of the present invention. For example, while the embodiments described above refer to particular features, the scope of this invention also includes embodiments having different combinations of features and embodiments that do not include all of the described features. Accordingly, the scope of the present invention is intended to embrace all such alternatives, modifications, and variations as fall within the scope of the claims, together with all equivalents thereof.
Number | Date | Country | Kind |
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0700622 | Jan 2007 | FR | national |
The present application is a continuation of U.S. patent application Ser. No. 14/069,158, entitled Intra-Articular Joint Replacement, filed Oct. 31, 2013, which is a continuation of U.S. patent application Ser. No. 12/787,124, entitled Intra-Articular Joint Replacement, filed May 25, 2010, which is a continuation of U.S. patent application Ser. No. 12/337,385, entitled Intra-Articular Joint Replacement, filed Dec. 17, 2008, which is a continuation-in-part of U.S. patent application Ser. No. 12/020,913, entitled Method and Apparatus for Fitting a Shoulder Prosthesis, filed Jan. 28, 2008, which claims priority to French application No. 0700622, entitled “Méthode et ensemble d'instrumentation chirurgicale pour poser une prothèse totale d'épaule inversée, et prothèse correspondante,” filed Jan. 30, 2007, and also claims the benefit of U.S. Provisional Application Ser. Nos. 60/888,437 filed Feb. 6, 2007 and 60/971,762 filed Sep. 12, 2007, both entitled “Method and Apparatus for Fitting an Inverted Shoulder Prosthesis,” and U.S. Provisional Application Ser. No. 61/015,042, entitled “Intra-Articular Joint Replacement,” filed Dec. 19, 2007, the complete disclosures of which are hereby incorporated by reference.
Number | Date | Country | |
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60888437 | Feb 2007 | US | |
60971762 | Sep 2007 | US | |
61015042 | Dec 2007 | US |
Number | Date | Country | |
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Parent | 14069158 | Oct 2013 | US |
Child | 14754506 | US | |
Parent | 12787124 | May 2010 | US |
Child | 14069158 | US | |
Parent | 12337385 | Dec 2008 | US |
Child | 12787124 | US |
Number | Date | Country | |
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Parent | 12020913 | Jan 2008 | US |
Child | 12337385 | US |