THE INFLUENCE OF TIBIAL POSTERIOR SLOPE CHANGES ON JOINT GAP AND RANGE OF MOTION IN UNICOMPARTMENTAL KNEE ARTHROPLASTY

Abstract

The influence of amount of tibial posterior slope changes on joint gap and postoperative range of motion was investigated in 35 patients undergoing unicompartmental knee arthroplasty (UKA). Component gap between the medial tibial osteotomy surface and the femoral trial prosthesis was measured throughout the range of motion using a tensor. The mean tibial posterior slope decreased from 10.2 to 7.3 degrees. Increased tibial slope change was positively correlated with component gap differences of 90° −10°, 120° −10°, and 135° −10° and negatively correlated with postoperative extension angle. Increasing tibial slope should be avoided to achieve full extension angle after UKA.