Fixed- vs mobile-bearing total knee arthroplasty: does it make a difference?--a prospective randomized study.

The purpose of this prospective, randomized study was to compare the early clinical and functional results of primary total knee arthroplasty using a fixed-bearing (FB) and a rotating-platform (RP) prosthesis. Outcomes including range of motion (ROM), Knee Society Score, Western Ontario MacMaster (WOMAC), and Short Form-36 (SF-36) were measured preoperatively and at 6 weeks, 3 months, 6 months, 1 year, and 2 years. Radiographic analysis was performed. There were 72 FB and 68 RP knees. The RP group had a greater ROM at 6 weeks and 1 year. This difference was not statistically significant at 2 years. There were no differences in the ROM at any other period. There were no significant differences in Knee Society Score, Short Form-36, or Western Ontario MacMaster scores at any period. No clinically significant differences were noted in the radiographic analysis. The use of a FB or RP design did not affect the early functional outcomes after total knee arthroplasty.