During a 10-year follow-up study of patients with hip pain, the prevalence of radiographic hip osteoarthritis (OA) increased steadily, but pain was reduced and function remained stable. These findings were published in Osteoarthritis.
Researchers from University Medical Center in The Netherlands analyzed data from the Cohort Hip and Cohort Knee (CHECK) study, which recruited 1002 patients with hip or knee pain or both between 2002 and 2005. Patients were assessed for long-term clinical outcomes and instance of hip replacements.
Among the subset of patients (n=588) who reported hip pain, 71% had both hip and knee pain and 29% had hip pain alone. At baseline, patients had a mean age of 55.8 years (SD, 5.2), 81% were women, and average body mass index was 26.1 kg/m2 (SD, 4.1).
A minority of study participants (19%) had rheumatoid OA of the hip and nearly a third (27%) met the criteria for American College of Rheumatology (ACR) hip OA. More patients who had hip-only pain had rheumatoid OA (23%) or ACR OA (30%) compared with the hip and knee group (17% and 26%, respectively).
At the year 10 follow-up, 53% of patients had rheumatoid OA or ACR OA in at least 1 hip. Half of patients (51%) reported their hip pain still persisted, but fewer reported morning hip stiffness (45%) than at baseline (55%), pain intensity decreased from 3.7 (SD, 2.1) to 2.9 (SD, 2.6), Western Ontario and McMaster Osteoarthritis index (WOMAC) functioning scores remained stable (mean, 17.2±12.0 vs 16.2±13.1), and pain medication use increased from 43% to 50%.
A total of 69 hip replacements were performed, primarily among the hip pain only group (22%) rather than among the hip and knee pain cohort (7%). In the years preceding the replacement surgery, more patients met the ACR OA criteria (69% to 88%) than rheumatoid OA criteria (19% to 35%).
Among the patients who received a hip replacement, at 10 years pain intensity decreased by 1.9 points (on a 10-point scale), WOMAC pain intensity subscores decreased by 2.6 points, and WOMAC physical function subscores decreased by 8.1 points.
This study was limited by not assessing all patients with the WOMAC during each follow-up, instead asking patients to rate their general, nonlocalized joint pain during the past week on a scale of 1 to 10.
After 10 years of seeking medical attention for hip pain, although instances of ACR OA and rheumatoid OA increased, pain tended to decrease, and clinical symptoms of function remained stable.
Van Berkel AC, Schiphof D, Waarsing JH, et al. 10-year natural course of early hip osteoarthritis in middle-aged persons with hip pain: a CHECK study. Published online January 15, 2021. Ann Rheum Dis. doi:10.1136/annrheumdis-2020-218625