Abstract:
A method of resurfacing a glenoid according to an according to an exemplary aspect of the present disclosure includes resurfacing a first section of a glenoid surface with and implant while leaving a second section of the glenoid surface uncovered by the implant.

Description:
BACKGROUND 
       [0001]    This disclosure relates to joint resurfacing components and methods. 
         [0002]    Known shoulder joint resurfacing methods include resurfacing the entire articulating surface of the glenoid. Advancements in this field of technology are desirable, especially when they pertain to less invasive solutions that expand the continuum of patient care options. 
       SUMMARY 
       [0003]    This disclosure details exemplary joint resurfacing methods and components during surgical procedures, such as glenoid resurfacing procedures. The components include an implant for placement on one surface of a joint for articulation with another surface. 
         [0004]    A method of resurfacing a glenoid according to an according to an exemplary aspect of the present disclosure includes resurfacing a first section of a glenoid surface with and implant while leaving a second section of the glenoid surface uncovered by the implant. 
         [0005]    A method of resurfacing a glenoid according to an exemplary aspect of the present disclosure includes fixating an implant to a glenoid. The glenoid includes first and second concave surfaces, and the implant is fixated to only cover one of the first and second concave surfaces. 
         [0006]    An implant for resurfacing a joint according to according to an exemplary aspect of the present disclosure includes an articulating surface component. A baseplate component is configured to receive the articulating surface component and includes a plurality of removable scores for customizing a size of the baseplate component. 
         [0007]    The embodiments, examples and alternatives of the preceding paragraphs, the claims, or the following description and drawings, including any of their various aspects or respective individual features, may be taken independently or in any combination. Features described in connection with one embodiment are applicable to all embodiments, unless such features are incompatible. 
         [0008]    The various features and advantages of this disclosure will become apparent to those skilled in the art from the following detailed description. The drawings that accompany the detailed description can be briefly described as follows. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  illustrates an example resurfaced joint. In this example, the resurfaced joint is a shoulder. 
           [0010]      FIG. 2 a    illustrates a top view of a glenoid experiencing a first amount of deterioration. 
           [0011]      FIG. 2 b    illustrates a top view of a glenoid experiencing a second amount of deterioration. 
           [0012]      FIG. 3  illustrates an example resurfaced joint. 
           [0013]      FIG. 4  illustrates another example resurfaced joint. 
           [0014]      FIG. 5  illustrates a modular implant. 
           [0015]      FIG. 6  illustrates a scored baseplate. 
       
    
    
     DETAILED DESCRIPTION 
       [0016]    This disclosure describes components and methods for joint resurfacing. For example, the components or methods could be used in glenoid resurfacing and/or a shoulder replacement procedure. 
         [0017]    In some embodiments, the joint is a shoulder, and a partial surface of the glenoid of the shoulder is resurfaced with an implant. These and other features are described in greater detail in the following paragraphs of this detailed description. 
         [0018]      FIG. 1  illustrates an example joint  20 . In this non-limiting example, the joint  20  is a shoulder. The joint  20  includes a surface  24  of a glenoid cavity (“glenoid”)  26  of a scapula  27 . The surface  24  interfaces with an articulating surface  28  of a humerus  30 . The humerus  30  could be a prosthetic humerus or the existing or native humerus of the patient. Over time, arthritis may develop and cause deterioration in all or part of the glenoid  26 . The glenoid  26  may be resurfaced to repair the joint. Exemplary resurfacing techniques &amp; devices are detailed below. 
         [0019]      FIGS. 2 a  and 2 b    illustrate top views of example deterioration that could occur in the glenoid  26 . In this pathological situation, the glenoid  26  is the native glenoid. Glenoid shapes in osteoarthritis include what may be referred to as B1 or B2 glenoids characterized by posterior humeral subluxation or malalignment.  FIG. 2 a    illustrates what may be referred to as a B1 glenoid. In a B1 glenoid, the humerus  30  has subluxated toward the posterior section  32  of the glenoid  26 , which may result in deterioration of the posterior section  32  of the glenoid  26 . 
         [0020]      FIG. 2 b    illustrates what may be referred to as a B2 glenoid. In a B2 glenoid, the humerus  30  has subluxated toward the posterior section  32  of the glenoid  26  such that a first concave surface  33  and a second concave surface  34  have formed in the glenoid surface  24 . The surface  24  of a B2 glenoid is thus considered biconcave. A B1 glenoid may progress into a B2 glenoid. 
         [0021]      FIG. 3  illustrates a first example resurfacing of a glenoid  26 . In this non-limiting example, the glenoid  26  is a B2 glenoid, and an implant  22  is fixated to the concave surface  34  at the posterior section  32  of the glenoid  26 . The implant  22  includes an articulating surface  36  configured to interface with the articulating surface  28  of the humerus  30 . In one non-limiting example, the articulating surface  36  of the implant  22  is made of plastic. In another non-limiting example, the articulating surface  36  of the implant  22  is made of a biologic material, such as bone, or allograft bone. The implant  22  further includes an attachment feature  38  configured for attachment to the glenoid  26 . In one example, the attachment feature  38  is an elongated member configured for extension into the scapula  27 . The attachment feature  38  may be a keel, peg, screw, or a plurality of cemented or cementless features to enhance fixation or rotational support to aide in fixation and rotation support. 
         [0022]    In this non-limiting example, the posterior section  32  of the surface  24  of the glenoid  26  is resurfaced, while the anterior section  40  of the surface  24  of the glenoid  26  is not covered by the implant  22  and therefore not resurfaced. Thus, because the concave surface  34  articulates with the humerus  30  and the concave surface  33  does not, only a portion of the glenoid  26  is resurfaced with the implant  22 . In this example, the humerus  30  is left to articulate in its non-anatomic position at the posterior section  32  of the glenoid  26 . The width W 1  of the articulating surface  36  of the implant  22  is less than the width W 2  of the surface  24  of the glenoid  26 , such that the surface area of the implant  22  is less than the surface area of the surface  24  of the glenoid  26 . 
         [0023]    Although the resurfaced section of the glenoid  26  in the example is the posterior section  32 , the anterior section  40  could alternatively be the resurfaced section. In the case of a B2 glenoid, one of the concave surfaces  33 ,  34  is resurfaced, while the other of the concave surfaces  33 ,  34  is not resurfaced. In another example, the glenoid  26  may be partially resurfaced such that a central section of the glenoid  26  is resurfaced, while a peripheral section is not resurfaced. 
         [0024]      FIG. 4  illustrates a second example glenoid resurfacing. In this non-limiting example, the glenoid  26  is a B2 glenoid, and the glenoid  26  is partially resurfaced to return the humerus  30  to its anatomic position. An implant  22  is fixated at the concave surface  34  at the posterior section  32  of the glenoid  26 . The implant  22  includes an articulating surface  36  configured to interface with the articulating surface  28  of the humerus  30 . The implant  22  further includes an attachment feature  38  configured for attachment to the glenoid  26 . 
         [0025]    In one non-limiting example, a graft or augment  42  (biologic or metallic) may be located between the articulating surface  36  of the implant  22  and the concave surface  34 . In addition to improving fixation, the graft  42  may space the articulating surface  36  from the surface  34  and orient the implant  22  and articulating surface  36  in such a way that the articulating surface  36  and the surface  33  create a single concave articulating surface either at the time of implantation or following an interfacing with the humerus  30 . 
         [0026]    In this non-limiting example, the concave surface  34  at the posterior section  32  of the surface  24  of the glenoid  26  is resurfaced, while the concave surface  33  at the anterior section  40  of the surface  24  of the glenoid  26  is not covered by the implant  22  and therefore not resurfaced. The articulating surface  36  of the implant  22  and the surface  33  create a single concave surface for the glenoid  26 . The humerus  30  may then be re-centered into an anatomic position to articulate with both the implant  22  and the surface  33  of the partially resurfaced glenoid  26 . The width W 1  of the articulating surface  36  of the implant  22  is less than the width W 2  of the surface  24  of the glenoid  26 , such that the surface area of the implant  22  is less than the surface area of the surface  24  of the glenoid  26 . 
         [0027]    Although the resurfaced section of the glenoid  26  in the example is the posterior section  32 , the anterior section  40  may be the resurfaced section. In the case of a B2 glenoid, one of the concave surfaces  33 ,  34  is resurfaced, while the other of the concave surfaces  33 ,  34  is not resurfaced. 
         [0028]    The disclosed non-limiting methods thus describe partial joint resurfacing of a B2 glenoid to allow for articulation of the humeral head in an anatomic position by re-centering the humeral head or in a non-anatomic position by not re-centering the humeral head. The disclosed methods may be used to treat a B2 glenoid or to slow the progression of a B1 glenoid into a B2 glenoid or any such progressive pathology. The disclosed methods may also be used to treat other types of partially worn glenoids. 
         [0029]    Referring to  FIG. 5 , the implant  22  may be modular in nature. The implant  22  may include an articulating surface component  50  that includes the articulating surface  36 . In shoulder applications, for example, the width W 1  of the articulating surface  36  of the implant  22  is less than the width of the surface of the glenoid  26 . The articulating surface component  50  is configured for attachment to a baseplate component  52 . The baseplate component  52  is configured for attachment to the resurfaced joint. In one non-limiting example, the articulating surface component  50  is made of plastic, one example being a polyethylene, and the baseplate component  52  is metallic. In another non-limiting example, the articulating surface component  50  is made of a biologic material, such as, but not limited to, bone or allograft bone. 
         [0030]      FIG. 6  illustrates one example baseplate  52 . The baseplate  52  may include scores  54  to allow for easy size customization to the resurfaced section of the joint, such as the glenoid in the shoulder. The baseplate  52  includes removable incremental scores  54  for customization of the size of the implant  22  to fit the partial surface of the joint. The scores  54  may be broken off to create a custom sized baseplate. 
         [0031]    Another non-limiting example implant  22  may be an all biologic implant. The implant may be an allograft where bone and cartilage are implanted onto a defect to resurface a damaged glenoid  26 . 
         [0032]    Another non-limiting example implant  22  may be an all polyethylene implant. The polyethylene implant may be cemented into place. The polyethylene may include an attachment feature  38  such as a keel or peg to aide in fixation and rotation support. 
         [0033]    Although the different non-limiting embodiments are illustrated as having specific components, the embodiments of this disclosure are not limited to those particular combinations. It is possible to use some of the components or features from any of the non-limiting embodiments in combination with features or components from any of the other non-limiting embodiments. 
         [0034]    It should be understood that like reference numerals identify corresponding or similar elements throughout the several drawings. It should also be understood that although a particular component arrangement is disclosed and illustrated in these exemplary embodiments, other arrangements could also benefit from the teachings of this disclosure. 
         [0035]    The foregoing description shall be interpreted as illustrative and not in any limiting sense. A worker of ordinary skill in the art would understand that certain modifications could come within the scope of this disclosure. For these reasons, the following claims should be studied to determine the true scope and content of this disclosure.