A five to seven year follow-up comparing computer-assisted vs freehand TKR with regard to clinical parameters

Purpose Computer-assisted knee surgery has become established in routine clinical practice. Still, there is no study investigating midterm clinical outcome after five to seven years postoperatively. We aimed to test the hypothesis that there is no difference either for subjective [Western Ontario and McMaster Universities (WOMAC) scores] or for objective (Knee Society Score, degree of flexion) criteria between computer-assisted total knee replacement (TKR) and freehand TKR after 5.6-7.3 years. Methods We performed a matched-pair analysis; 100 patients who received a primary TKR were investigated after a median follow-up of 6.25 years. Group A was operated on with the support of a computer system, while surgery on patients in group B was performed with the freehand technique. We determined WOMAC Score, Knee Society Score and degree of flexion. Results Overall we found similar results for WOMAC Score [group A: 42.98 (SD 13.80); group B: 41.54 (SD 15.01; p=0.62)], Knee Society Score [group A: 168.20 (SD 21.94); group B: 166.60 (SD 21.44; p=0.71)] and range of motion [group A: 106 degrees (SD 9.19); group B 107 degrees (SD 7.44; p=0.62)]. Conclusions No significant differences in midterm clinical outcome were found after TKR performed in the freehand vs computer-assisted technique.