Yttrium-90 radiosynovectomy in knees and ankles (25 joints in 22 hemophilic patients). Short-term results.

INTRODUCTION: The radiosynovectomy (RS) is one treatment option for recurrent hemarthrosis in patients with hemophilia (PWH). A prospective cohort study was designed to evaluate the effects of the RS on the synovial membrane volume in the ankles and knees of PWH and patient characteristics related to the RS outcome. METHODS: In a one-year follow-up, 25 joints of 22 PWH who presented 3 bleeds or more in the same joint over the last 6 months (target joints) were subjected to the RS. Two groups were compared: those who retained target joints following the RS and those who did not (less than 3 bleeds/6 months after the RS). The groups were analyzed according to age, hemophilia type/severity, joint, body mass index (BMI), inhibitor and Hemophilia Joint Health Score 2.1 (HJHS). The magnetic resonance images (MRI) of six ankles and six knees were acquired prior to, and 6 months after, the RS. The synovial membrane volume and arthropathy MRI scale were accessed and volumes were compared and correlated with the Yttrium-90 dose injected. RESULTS: Patients with a mean age of 12 years and a mean HJHS of 6.7 (p < 0.05) retained target joints after the RS. The inhibitor, joint, type/severity of disease and BMI showed no significant differences between groups. The synovial membrane volume had a significant reduction after the RS (p = 0.03), but no correlation with the Yttrium-90 dose. In proportion to the synovial membrane volume, doses injected to the ankles were larger than those injected to the knees. CONCLUSION: The synovial membrane volume is reduced after the RS, regardless of the effective 90Y dose.