The clinical and radiographic course of early knee and hip osteoarthritis over 10 years in CHECK (Cohort Hip and Cohort Knee).

Objective: To describe the radiographic and symptomatic course in subjects with hip or knee complaints suspected of early osteoarthritis (OA).

Design: CHECK (Cohort Hip and Cohort Knee) is a multicenter, prospective observational cohort study of 1,002 subjects with first complaints in knee(s) and/or hip(s) (age 56 ± 5 years; 79% female; body mass index (BMI) 26 ± 4 kg/m). Visits took place at baseline and at 2, 5, 8, and 10 year follow-up. At each visit, questionnaires were administered, physical examination performed, and X-ray images obtained. Clinical OA was defined according to the clinical American College of Rheumatism (ACR) criteria. Radiographic OA (ROA) was defined as Kellgren and Lawrence score (K&L) ≥2.

Results: 83% of the subjects reported knee pain, 59% hip pain, and 42% reported both hip and knee pain at baseline. 85% of the subjects completed 10-year follow-up. Pain scores remained rather stable over time, although individual scores fluctuated. A total of 138 subjects never fulfilled the clinical American College of Rheumatology (ACR) criteria. 60% (n = 601) had ROA in one or both knees, and 51% (n = 513) had ROA in one or both hips at 10 years. Only 13.5% of the subjects did not develop ROA after 10 years. Most joint replacements (n = 52 (57%)) took place in subjects with multiple affected joints.

Conclusions: The symptomatic course in subjects with hip or knee complaints suspected of OA remained fairly stable on population level, though individual scores fluctuated. The radiological course was progressive, with joint replacements particularly in subjects with both hip and knee OA.