Patella resection guide

Abstract

A method and apparatus for resectioning a patella without everting it includes a resection guide which grips the patella with gripping members, one of which can also function as an alignment guide for a surgeon using a saw for the resectioning. Means engageable with the resection guide are provided for aligning drills and/or reamers used in resectioning. Under one embodiment, a pair of reamers are provided for reaming the patella in two reaming operations.

1 - 22 . (canceled)  
   
   
       23 . A device for use in resectioning a patella having an anterior surface, a posterior surface and a circumferential edge between said anterior surface and said posterior surface comprising: 
 (a) a fixed engagement member having (i) a support upon which said patella anterior surface may rest and (ii) first patella engagement means for engaging said circumferential edge; and    (b) a movable engagement member having second patella engagement means for engaging at least a portion of said circumferential edge of a patella resting upon said support, said movable engagement member being slideably attached to said fixed engagement member for movement toward said first patella engagement means to engage at least a portion of the circumferential edge of said patella.    
   
   
       24 . A device according to  claim 23  wherein said movable engagement member has a planar surface spaced from said support, said planar surface being useable for guiding a cutting tool.  
   
   
       25 . A device according to  claim 24  wherein said planar surface defines one surface of a guide slot on said movable engagement member.  
   
   
       26 . A device according to  claim 24  further including an adjustment member engageable with said planar surface, said adjustment member having a second planar surface useable for guiding a cutting tool.  
   
   
       27 . A device according to  claim 23  wherein said fixed engagement member includes an arm terminating at said support and a post mounted on said arm at substantially right angles to said arm and further including a guide member supported on said post, said guide member having a passageway for guiding movement of a drill into said patella, and means for positioning said guide member on said post to position said passageway over a central portion of a patella engaged by said first and second patella engagement means.  
   
   
       28 . A device according to  claim 23  further including gripping means engaged to said movable engagement member, said gripping means includes an arm extending to a gripping portion, said arm positioned on the opposite side of said support from said first and second patella engagement means.  
   
   
       29 . A device according to  claim 28  wherein said fixed engagement member includes a first arm extending from said support in a direction away from said first patella engagement means to an area of juncture, said first arm having a longitudinal slot and a second arm spaced from and parallel to said first arm and wherein said movable engagement member includes a first slider member slideably engaged to said first arm on the opposite side of said first arm from said second patella engagement means and a second slider member slideably engaged to said second arm.  
   
   
       30 . A device according to  claim 29  further including a guide member secured to said fixed engagement member, said guide member having a passageway for guiding movement of a drill into said patella, and means for positioning said guide member on said fixed engagement member to position said passageway over a central portion of a patella engaged by said first and second patella engagement means.  
   
   
       31 . A device according to  claim 30  wherein (i) said means for positioning said guide member on said fixed engagement means includes a receptacle engaged to said first arm and (ii) said guide member being supported on a post engageable in said receptacle.  
   
   
       32 . A device according to  claim 31  wherein said guide member is adjustably supported on said post.  
   
   
       33 . A combination of a device according to  claim 23  and first and second reamers useable with said device, said first reamer having a circumferential cutter, inner and outer cylindrical walls extending from said circumferential cutter, said inner cylindrical wall defining a portion of a cavity terminating in an end wall spaced from said circumferential cutter and engageable with a central portion of said patella posterior surface to limit the depth to which said circumferential cutter can ream said patella, said second reamer having a central cutter and a circumferential non-cutting surface encircling said central cutter and sized to engage the portion of said patella reamed by said first reamer to limit the depth to which said central cutter can ream said patella.  
   
   
       34 . A resection device for a patella comprising a reamer having a circumferential cutter, inner and outer cylindrical walls extending from said circumferential cutter, said inner cylindrical wall defining a portion of a cavity terminating in an end wall spaced from said circumferential cutter and engageable with a central portion of said patella to limit the depth to which said circumferential cutter can ream said patella.  
   
   
       35 . A reamer for resectioning a patella partially reamed to leave a circumferential reamed surface comprising a central cutter and a circumferential non-cutting surface encircling said central cutter and sized to engage the partially reamed portion of said patella to limit the depth to which said reamer can ream said patella.  
   
   
       36 . A device for resectioning a patella comprising a combination of first and second reamers, said first reamer having a circumferential cutter, inner and outer cylindrical walls extending from said circumferential cutter, said inner cylindrical wall defining a portion of a cavity terminating in an end wall spaced from said circumferential cutter, said end wall engageable with a central portion of said patella posterior surface to limit the depth to which said circumferential cutter can ream said patella, said second reamer having a central cutter and a circumferential non-cutting surface encircling said central cutter, said non-cutting surface sized to engage the portion of said patella reamed by said first reamer to limit the depth to which said second reamer can ream said patella.