LAUSR

OBJECTIVE To determine the incidence and progression of ankle osteoarthritis (OA) and associated risk factors in a community-based cohort of African Americans and whites. METHODS Data were from 541 participants who had standardized lateral and mortise radiography of the ankles in weight bearing at baseline (2013-2015) and follow-up (2017-2018). Incident radiographic ankle OA (rAOA) was defined as a Kellgren-Lawrence grade (KLG) ≥ 1 at follow-up among ankles with baseline KLG < 1; progressive rAOA was a ≥ 1 KLG increase at follow-up among ankles with KLG ≥ 1 at baseline. Symptoms were assessed using self-reported pain, aching, and stiffness (PAS) on most days and the Foot and Ankle Outcome Score (FAOS) symptoms subscale. Ankle-level logistic regression models were used to assess associations of ankle outcomes with covariates (age, sex, race, body mass index [BMI], smoking, number of symptomatic joints, comorbidities, prior ankle injury, and knee or foot OA). RESULTS Among ankles without rAOA at baseline, 28% developed incident rAOA, 37% had worsening FAOS symptoms, and 7% had worsening PAS. Incident rAOA and worsening ankle symptoms were associated with higher BMI and symptoms in other joints. Among ankles with baseline rAOA, 4% had progressive rAOA, 35% had worsening of FAOS symptoms, and 9% had worsening PAS. rAOA progression was associated with ankle injury and concomitant knee or foot OA; worsening of symptoms was associated with higher BMI and other symptomatic joints. CONCLUSIONS Not all ankle OA is post-traumatic. Smoking prevention/cessation, a healthy weight, and injury prevention may be methods for reducing the incidence and progression of rAOA.