Purpose The ability to identify and focus care to patients at higher risk of moderate to severe postoperative pain should improve analgesia and patient satisfaction, and may affect reimbursement. We undertook this multi-centre crosssectional study to identify preoperative risk factors for moderate to severe pain after total hip (THR) and knee (TKR) replacement. Methods A total of 897 patients were identified from electronic medical records. Preoperative information and anaesthetic technique was gained by retrospective chart review. The primary outcomes were moderate to severe pain (pain score ≥4/10) at rest and with activity on postoperative day one. Logistic regression was performed to identify predictors for moderate to severe pain. Results Moderate to severe pain was reported by 20 % at rest and 33 % with activity. Predictors for pain at rest were female gender (OR 1.10 with 95 % CI 1.01-1.20), younger age (0.96, 0.94-0.99), increased BMI

NCT01248624.