Patient relevant outcome 7 years after total hip replacement for OA - a prospective study

Background: To investigate prospectively the patient-relevant outcome 7 years after total hip replacement (THR) for osteoarthritis (OA). Methods: 219 consecutive patients (120 women) with primary OA, mean age 71 (range 50-92) were assigned for THR. They were examined preoperatively, at 3, 6, 12 months, and at 4, 5 and 7 years postoperatively with the self-administered questionnaires SF-36 and WOMAC. Supplementary questions regarding postoperative complications, general co-morbidity, social circumstances and patient satisfaction were asked at the three last follow-ups. A reference group, 117 subjects (67 women), mean age 72 (range 52-92) without hip complaints were recruited from the community and investigated at the same times. Results: 151/170 (89%) of the patients and 65/74 (88%) of the reference group participated at the 7 year follow-up. The best postoperative result was reported one year postoperatively. At the 7 year follow up there was a significant difference between the patients and controls in SF-36 physical function (PF) and role physical (RP) but not of WOMAC function. There was no difference in frequency of co-morbid conditions between those operated and the reference group, but those operated were in greater need of walking aid (46% vs. 8% p < 0.0001) and reported more regional and widespread pain (68% vs. 53% p < 0.05). Conclusion: This study shows that in an unselected cohort the patients experience a similar health-related quality of life as a reference group of a similar age and sex structure 7 years after THR except for general physical function where the patients score worse.