Proportioned surgically implantable knee prosthesis

Abstract

A knee prosthesis for unicompartmental implantation into a knee joint is implantable without requiring bone resection and includes a body free of any means of fixation to a portion of knee joint, anatomy and having a substantially elliptical shape in plan and a pair of contoured opposed faces including a convex face and a concave face. A peripheral edge extends between the faces and includes a first side, a second side opposite the first side, a first end and a second end opposite the first end. A first dimension D is defined by the first end and the second end. A second dimension F is defined by the first side and the second side. The dimension F is from about 0.25 to about 1.5 of the dimension D.

1 . A knee prosthesis for unicompartmental implantation into a knee joint, the prosthesis being implantable without requiring bone resection comprising:
 a body having a substantially elliptical shape in plan and a pair of contoured opposed faces including a convex face and a concave face;   a peripheral edge extending between the faces and having a first side, a second side opposite the first side, a first end and a second end opposite the first end;   a first dimension D defined by the first end and the second end; and   a second dimension F defined by the first side and the second side, where the dimension F is from about 0.25 to about 1.5 of the dimension D.   
   
   
       2 . The prosthesis as defined in  claim 1  wherein the concave face includes an anterior to posterior radius A and the first dimension D, where D is from about 0.6 A to about 1.4 A. 
   
   
       3 . The prosthesis as defined in  claim 2  wherein the anterior to posterior radius A is equal to the first dimension D. 
   
   
       4 . The prosthesis as defined in  claim 2  wherein the second dimension F is 0.64 A. 
   
   
       5 . The prosthesis as defined in  claim 2  wherein the concave face includes a medial to lateral radius B of from about 0.25 A to about 1.0 A. 
   
   
       6 . The prosthesis as defined in  claim 5  wherein the radius B is 0.68 A. 
   
   
       7 . The prosthesis as defined in  claim 2  further comprising:
 a posterior portion; and   a posterior portion dimension E of from about 0.1 A to about 0.75 A.   
   
   
       8 . The prosthesis as defined in  claim 2  further comprising:
 a part center location;   a medial edge; and   a width from part center to medial edge dimension G of from about 0.096 A to about 0.48 A.   
   
   
       9 . The prosthesis as defined in  claim 2  further comprising:
 a posterior portion;   a posterior portion dimension E of from about 0.1 A to about 0.75 A;   a part center location;   a medial edge; and   a width from part center to medial edge dimension G of from about 0.096 A to about 0.48 A.   
   
   
       10 . The prosthesis as defined in  claim 7  wherein the posterior half dimension E=0.5 A. 
   
   
       11 . The prosthesis as defined in  claim 8  wherein the width from part center to medial edge dimension G=0.352 A. 
   
   
       12 . The prosthesis as defined in  claim 9  wherein the posterior half dimension E=0.5 A and the width from part center to medial edge dimension G=0.352 A. 
   
   
       13 . The prosthesis as defined in  claim 2  wherein the concave face includes an anterior sweep radius C to accommodate relative rotation between a femur and a tibia. 
   
   
       14 . The prosthesis as defined in  claim 13  wherein C is from about 0.5 A to about 2.0 A. 
   
   
       15 . The prosthesis as defined in  claim 14  wherein C=A. 
   
   
       16 . An implantable knee prosthesis for unicompartmental implantation into a knee joint comprising:
 a body free of any means of fixation to a portion of knee joint anatomy and having a substantially elliptical shape in plan and a pair of contoured opposed faces including a convex face and a concave face;   a peripheral edge extending between the faces and having a first side, a second side opposite the first side, a first end and a second end opposite the first end;   a first dimension D bounded by the first end and the second end; and   a second dimension F bounded by the first side and the second side, where the dimension F is from about 0.25 to about 1.5 of the dimension D.   
   
   
       17 . The prosthesis as defined in  claim 16  wherein the concave face has an anterior to posterior radius A and the first dimension D, where D is from about 0.6 A to about 1.4 A. 
   
   
       18 . The prosthesis as defined in  claim 17  wherein the concave face has a medial to lateral radius B of from about 0.25 A to about 1.0 A. 
   
   
       19 . The prosthesis as defined in  claim 17  further comprising:
 a posterior portion;   a posterior portion dimension E of from about 0.1 A to abut 0.75 A;   a part center location;   a medial edge; and   a width from part center to medial edge dimension G of from about 0.096 A to about 0.48 A.   
   
   
       20 . The prosthesis as defined in  claim 17  wherein the concave face has an anterior sweep radius C to accommodate relative rotation between a femur and a tibia. 
   
   
       21 . The prosthesis as defined in  claim 20  wherein C is from about 0.5 A to about 2.0 A. 
   
   
       22 . A knee prosthesis for unicompartmental implantation into a knee joint, the prosthesis being implantable without requiring bone resection comprising:
 a body free of any means of fixation to a portion of knee joint anatomy and having a substantially elliptical shape in plan and a pair of contoured opposed faces including a convex face and a concave face;   a peripheral edge extending between the faces and having a first side, a second side opposite the first side, a first end and a second end opposite the first end;   a first dimension D extending from the first end to the second end; and   a second dimension F extending from the first side to the second side, where the dimension F is from about 0.25 to about 1.5 of the dimension D.   
   
   
       23 . The prosthesis as defined in  claim 22  wherein the concave face has an anterior to posterior radius A and the first dimension D, where D is from about 0.6 A to about 1.4 A. 
   
   
       24 . The prosthesis as defined in  claim 23  wherein the concave face has a medial to lateral radius B of from about 0.25 A to about 1.0 A. 
   
   
       25 . The prosthesis as defined in  claim 23  further comprising:
 a posterior portion;   a posterior portion dimension E of from about 0.1 A to about 0.75 A;   a part center location;   a medial edge; and   a width from part center to medial edge dimension G of from about 0.096 A to about 0.48 A.   
   
   
       26 . The prosthesis as defined in  claim 23  wherein the concave face has an anterior sweep radius C to accommodate relative rotation between a femur and a tibia. 
   
   
       27 . The prosthesis as defined in  claim 26  wherein C is from about 0.5 A to about 2.0 A. 
   
   
       28 . A method of providing a knee prosthesis for unicompartmental implantation into a knee joint, the prosthesis being implantable without requiring bone resection comprising:
 providing a body of a substantially elliptical shape; and   providing oppositely oriented convex and concave surfaces on the body and an edge extending between the surfaces, the surfaces having a dimension D between opposite ends thereof, and a dimension F between opposite sides thereof, the dimension F being in the range of from about 0.25 to about 1.5 of the dimension D.   
   
   
       29 . The method as defined in  claim 28  further comprising:
 removing at least a portion of a meniscus in the knee joint;   measuring for a length dimension of the prosthesis;   measuring for a thickness dimension of the prosthesis;   inserting a trial component into the knee joint;   verifying sizing for the trial component;   removing the trial component; and   inserting the prosthesis.   
   
   
       30 . A method of providing an implantable knee prosthesis for unicompartmental implantation into a knee joint comprising:
 providing a body free of any means of fixation to a portion of knee joint anatomy, the body being of a substantially elliptical shape; and   providing oppositely oriented convex and concave surfaces on the body and an edge extending between the surfaces, the surfaces having a dimension D between opposite ends thereof, and a dimension F between opposite sides thereof, the dimension F being in the range of from about 0.25 to about 1.5 of the dimension D.   
   
   
       31 . The method as defined in  claim 30  further comprising:
 removing at least a portion of a meniscus in the knee joint;   measuring for a length dimension of the prosthesis;   measuring for a thickness dimension of the prosthesis;   inserting a trial component into the knee joint;   verifying sizing for the trial component;   removing the trial component; and   inserting the prosthesis.   
   
   
       32 . A method of providing a knee prosthesis for unicompartmental implantation into a knee joint, the prosthesis being implantable without requiring bone resection comprising:
 providing a body free of any means of fixation to a portion of knee joint anatomy, the body being of a substantially elliptical shape; and   providing oppositely oriented convex and concave surfaces on the body and an edge extending between the surfaces, the surfaces having a dimension D between opposite ends thereof, and a dimension F between opposite side thereof, the dimension F being in the range of from about 0.25 to about 1.5 of the dimension D.   
   
   
       33 . The method as defined in  claim 32  further comprising:
 removing at least a portion of a meniscus in the knee joint;   measuring for a length dimension of the prosthesis;   measuring for a thickness dimension of the prosthesis;   inserting a trial component into the knee joint;   verifying sizing for the trial component; and   inserting the prosthesis.