Early Revision for Component Malrotation in Total Knee ArthroplastyIncavo, Stephen J, MD; Wild, John J, MD; Coughlin, Kathryn M, MS; Beynnon, Bruce D, PhD
Component malrotation may result in unsuccessful total knee arthroplasty. We asked whether revision improves function in patients with malrotated total knee arthroplasty components. We retrospectively reviewed 22 revision total knee arthroplasties performed for femoral and/or tibial component malrotation. Revision surgery was performed within 2 years of the primary arthroplasty in 81% of the cases (18 of 22) with the remainder within 5 years. Although all patients had pain, 32% of patients had associated instability and 36% of patients had poor range of motion. Average Knee Society Scores improved from 42 preoperatively to 77 postoperatively. Average Oxford Knee Scores improved from 38 preoperatively to 29 postoperatively. Although clini cal and functional improvement was observed, these results are inferior to those for primary knee arthroplasty, and they emphasize the need for proper component rotational positioning during primary total knee arthroplasty. Internal component malrotation leads not only to patellofemoral problems, but also to difficulty in gap balancing and femoral component sizing, which may in turn lead to either poor range of motion or symptoms of knee instability.
Level of Evidence: Level IV, diagnostic study. See the Guide lines for Authors for a complete description of levels of evidence.