Does High-flexion Design of Cruciate Retaining Total Knee Prosthesis Increase Postoperative Range of Motion?

INTRODUCTION: The range of motion (ROM) after total knee arthroplasty (TKA) is one of the most important factors for patient satisfaction, especially in Asian countries. To enhance the knee flexion angle, “highflexion” designs have been introduced in total knee prostheses. One of such design was a new design of femoral prosthesis, which increased the posterior cut on the bone by 2 mm and thickened the posterior condyle, allowing the posterior condylar radius to continue further (Figure 1). There were several reports on postoperative ROM of such “highflexion” posterior-stabilized (PS) total knee prosthesis (1,2). However, there was no report on the postoperative ROM of “high-flexion” cruciate ligament retaining (CR) total knee prosthesis. The purpose of this study was to compare the ROM associated with standard and high-flexion posterior CR total knee prostheses.