A Retrospective Analysis of Balance Function After Unilateral Total Knee Arthroplasty in Patients With Bilateral Knee Osteoarthritis.

PURPOSE: Total knee arthroplasty (TKA) is widely recognized for its efficacy in reducing pain and improving both static and dynamic balance in individuals with end-stage knee osteoarthritis (OA). However, the sustainability of these improvements after unilateral TKA in patients with bilateral knee OA remains unclear. METHODS: This retrospective study analyzed the medical records of patients with bilateral knee OA (Kellgren-Lawrence grade ≥3) who underwent unilateral TKA of the more symptomatic knee and did not undergo contralateral TKA within one year. Balance function was assessed using the timed up and go (TUG) test and the one-leg standing (OLS) test at three time points: preoperatively, six months postoperatively, and at the final follow-up (≥1 year postoperatively). RESULTS: A total of 51 patients were included in the analysis. Both TUG and OLS times showed significant improvement from the preoperative period to six months postoperatively. At the final follow-up, the balance function showed a decline, suggesting a loss of the initial benefits of unilateral TKA. CONCLUSION: Unilateral TKA significantly improves balance function in patients with bilateral knee OA. Although these improvements tended to decline over time, the underlying factors could not be determined in this retrospective study. These findings support the importance of longitudinal follow-up and may assist in clinical decision-making regarding staged bilateral TKA.