Preoperative sleep quality as a predictor of postoperative pain, function, and recovery after total knee arthroplasty: a prospective cohort study

Sleep quality is increasingly recognized as a key determinant of surgical recovery; however, evidence regarding its longitudinal relationship with postoperative recovery outcomes after total knee arthroplasty remains limited. Poor preoperative sleep may impair postoperative pain control, mobility, and functional independence. Therefore, this study examined the effect of preoperative sleep quality on postoperative sleep, pain, range of motion, and activities of daily living in patients undergoing total knee arthroplasty. A prospective cohort study was conducted with 70 patients undergoing primary total knee arthroplasty at a university hospital between February 2023 and December 2024. Data were collected at three time points preoperatively, and at 30 and 90 days postoperatively using the Pittsburgh Sleep Quality Index, Visual Analog Scale, goniometric range of motion measurement, and the Modified Barthel Index. Statistical analyses included Friedman tests with Bonferroni-adjusted post hoc comparisons, correlation analyses, and multiple regression models. Preoperative sleep quality significantly predicted postoperative sleep quality (β = 0.970, p < 0.001) and pain intensity (β = 0.091, p = 0.046). Poor sleep quality was negatively correlated with range of motion and activities of daily living at 90 days postoperatively. Preoperative sleep quality plays a meaningful prognostic role in postoperative recovery following total knee arthroplasty. Integrating routine sleep assessment and sleep-focused nursing interventions into perioperative care may optimize recovery trajectories, improve pain control, and enhance functional independence. Nurses should incorporate sleep quality screening into preoperative evaluations and implement integrated sleep–pain management strategies to support holistic recovery and potentially improve postoperative rehabilitation outcomes.