Does postoperative exercise after hip arthroplasty improve strength and function? A systematic review and meta-analysis

OBJECTIVE: To determine the clinical benefits of structured postoperative exercise on muscle strength, patient-reported function, and range of motion after total hip arthroplasty (THA) for osteoarthritis. METHODS: We searched multiple databases for randomized controlled trials and prospective studies comparing structured exercise versus standard care after primary THA. Pooled effects were calculated using standardized mean differences (SMD) or mean differences (MD) with random‑effects models. Subgroup analyses were stratified by follow‑up duration (< 3 months, 3-6 months, > 12 months) and assessed limb (operated vs. healthy). RESULTS: Twenty‑two studies (1,782 participants) were included. For hip abduction strength, exercise significantly improved short‑term (< 3 months; SMD ‑0.78, 95% CI: ‑1.19 to ‑0.36) and mid‑term (3-6 months; SMD ‑0.69, 95% CI: ‑1.10 to ‑0.29) outcomes, but not long‑term (> 12 months; SMD ‑0.29, 95% CI: ‑0.75 to 0.17). Hip flexion strength showed no significant effect (SMD 0.10, 95% CI: ‑0.27 to 0.47). The Harris Hip Score improved significantly at 2 weeks (MD ‑4.62), 4 weeks (MD ‑7.67), 6 weeks (MD ‑17.83), and 12 weeks (MD ‑3.05), but the 1‑year effect was uncertain (MD ‑17.94, 95% CI: ‑49.13 to 13.25; I²=99.1%). Hip range of motion analysis was inconclusive (I²=94.4%). GRADE certainty was moderate for short‑/mid‑term hip abduction strength and early HHS improvements, and low to very low for other outcomes. CONCLUSION: Structured postoperative exercise provides short‑ to mid‑term improvements in hip abduction strength and early patient‑reported function, but long‑term efficacy and effects on hip flexion strength remain unconfirmed.