Partial joint resurfacing implant, instrumentation, and method

Abstract

An implant for repairing an articular cartilage defect site including an implant fixation portion with an upper segment and at least one bone interfacing segment and a top articulating portion with an articulating surface and an engagement surface. The upper segment includes a supporting plate with a first locking mechanism segment. The engagement surface includes a second locking mechanism segment. The first locking mechanism segment with at least two channels is structured to couple to the second locking mechanism segment with at least two protrusions. The at least one bone interfacing segment structured for insertion into the articular cartilage defect site. An implant including an implant fixation portion, a top articulating portion, and a locking mechanism with a first locking segment coupled to the upper segment and a second locking segment coupled to the at least one engagement surface and structured to couple to the first locking segment.

What is claimed is: 
     
         1 . An implant for repairing an articular cartilage defect site, the implant comprising:
 a top articulating portion; and   a supporting plate, the supporting plate comprising a top surface and a bottom surface, wherein the top surface of the supporting plate is coupled to the top articulating portion and the bottom surface of the supporting plate being configured to facilitate insertion into the articular cartilage defect site.   
     
     
         2 . The implant of  claim 1 , wherein the implant has a cross-sectional shape, the cross-sectional shape being one of an oval, a rectangle, or an oblong shape. 
     
     
         3 . The implant of  claim 2 , wherein the cross-sectional shape of the implant is oblong. 
     
     
         4 . The implant of  claim 2 , wherein the supporting plate further comprises:
 at least one implant fixation portion, wherein the at least one implant fixation portion is integrally connected to and extending away from the bottom surface of the supporting plate.   
     
     
         5 . The implant of  claim 4 , wherein the at least one implant fixation portion comprises:
 at least one stem, wherein the at least one stem further comprises:
 a proximal cylindrical section; and 
 a distal bone fixation section, wherein at least two barbs project away from an outer surface of the distal bone fixation section. 
   
     
     
         6 . The implant of  claim 5 , wherein the at least one stem is two stems. 
     
     
         7 . The implant of  claim 6 , wherein the two stems are equally spaced apart along a longitudinal axis of the supporting plate. 
     
     
         8 . The implant of  claim 3 , wherein the top articulating portion comprises:
 an articulating surface; and   an engagement surface.   
     
     
         9 . The implant of  claim 8 , wherein the supporting plate comprises:
 an upper segment, wherein the upper segment is configured to couple to the engagement surface.   
     
     
         10 . The implant of  claim 9 , wherein the engagement surface comprises:
 at least two protrusions coupled to and extending away from the engagement surface of the top articulating portion, wherein the at least two protrusions have tapered edges.   
     
     
         11 . The implant of  claim 10 , wherein the upper segment comprises:
 at least two channels recessed into the top surface of the supporting plate, wherein the at least two channels have tapered edges extending from a top surface of the upper segment toward the at least one implant fixation portion.   
     
     
         12 . The implant of  claim 11 , wherein the at least two protrusions form a cross-shape and a center point of each protrusion overlaps with a center point of the engagement surface. 
     
     
         13 . The implant of  claim 12 , wherein the at least two channels form a cross-shape wherein a center point of each of the channels overlaps a center point of the upper segment. 
     
     
         14 . The implant of  claim 13 , wherein the at least two protrusions of the engagement surface of the top articulating portion engage the at least two channels on the upper segment of the supporting plate. 
     
     
         15 . The implant of  claim 14 , wherein the at least two protrusions terminate before reaching an outer perimeter of the top articulating portion, and wherein the at least two channels terminate before reaching an outer perimeter of the supporting plate. 
     
     
         16 . The implant of  claim 1 , wherein the supporting plate further comprises:
 at least two implant fixation portions integrally connected to and extending away from the bottom surface of the supporting plate.   
     
     
         17 . The implant of  claim 16 , wherein the implant has an oblong a cross-sectional shape. 
     
     
         18 . The implant of  claim 16 , wherein the top articulating portion comprises:
 an articulating surface; and   an engagement surface comprising:
 at least two protrusions coupled to and extending away from the engagement surface of the top articulating portion, wherein the at least two protrusions have tapered edges, wherein the at least two protrusions form a cross-shape and a center point of each protrusion overlaps with a center point of the engagement surface, and wherein the at least two protrusions terminate before reaching an outer perimeter of the top articulating portion. 
   
     
     
         19 . The implant of  claim 18 , wherein the supporting plate comprises:
 an upper segment comprising:
 at least two channels recessed into the top surface of the supporting plate, wherein the at least two channels have tapered edges extending from a top surface of the upper segment toward the at least two implant fixation portions, wherein the at least two channels form a cross-shape, wherein a center point of each of the channels overlaps a center point of the upper segment, and wherein the at least two channels terminate before reaching an outer perimeter of the supporting plate; wherein the upper segment is configured to couple to the engagement surface. 
   
     
     
         20 . The implant of  claim 19 , wherein the at least two protrusions of the engagement surface of the top articulating portion engage the at least two channels on the upper segment of the supporting plate.