Characteristics associated with joint replacement in early symptomatic knee or hip osteoarthritis: 6-year results from a nationwide prospective cohort study (CHECK).

BACKGROUND: Many patients with osteoarthritis (OA) of the knee and/or hip undergo total joint replacement (TJR) because of severely progressed symptoms.

AIM: To determine patient and disease characteristics associated with undergoing TJR in participants with recent-onset knee and/or hip OA.

DESIGN AND SETTING: Participants with hip or knee pain from the nationwide prospective Cohort Hip and Cohort Knee (CHECK) study were included.

METHOD: The outcome measure was total hip arthroplasty (THA) or total knee arthroplasty (TKA) during 6 years of follow-up. Joint-dependent characteristics were compared using generalised estimating equations (GEE). Multivariable models were built for both subgroups. Differences in symptomatic and radiographic progression were determined between baseline and 2-year follow-up (T2).

RESULTS: The knee subgroup included 751 participants (1502 knees), and there were 538 participants in the hip subgroup (1076 hips). Nineteen participants (22 knees) underwent TKA and 53 participants (62 hips) THA. Participants who underwent TKA had higher baseline body mass index, painful knee flexion, and higher Kellgren and Lawrence scores. Participants who underwent THA had painful internal hip rotation and showed more severe radiographic OA features. Participants who underwent TKA or THA showed more rapid symptomatic and radiographic OA progression at T2.

CONCLUSION: In patients with recent-onset knee or hip pain, radiographic OA features already exist and a substantial number of patients fulfil existing criteria for knee and hip OA. A trend was observed in rapid progression of radiographic and symptomatic OA severity among patients with TKA and THA. Early detection of OA by the GP is important in managing knee and hip OA.