Comparison of femoral component rotational axes in computer-assisted total knee arthroplasty using the gap technique: A retrospective study

Abstract

© 2018, Medical Association of Thailand. All rights reserved. Objective: To compare the deviation of three femoral rotational axes in computer assisted surgery [CAS] total knee arthroplasty [TKA] using the gap technique. Materials and Methods: A retrospective cross-sectional study was conducted between 2004 and 2013 at the Department of Orthopaedics, Ramathibodi Hospital of patients who had undergone computer-assisted total knee arthroplasty. All patients were included with the exception of those who had had post-traumatic knee osteoarthritis, valgus knee, or trapezoidal medial-lateral gap. Baseline characteristics and femoral rotational axes (Whiteside, posterior condyle, and transepicondyle) were recorded. Comparison among the three axes was performed using analysis of variance. Results: The study included 140 patients (114 women and 26 men) with an average age of 71.6±8.4 years, representing 140 total knee arthroplasties. The deviation of femoral component rotation axes were: Whiteside’s line 0.42±4.49 degrees, posterior condylar line -1.43±4.82 degrees and transepicondylar line -3.93±5.00 (p<0.001). Conclusion: Whiteside’s line showed the smallest deviation in femoral component rotation compared to the gap technique in CAS TKA.