What patient, joint and isotope characteristics influence the response to radiosynovectomy in patients with haemophilia?

The literature describes radiosynovectomy (RS) as a good non-surgical option for reducing synovial membrane size and thus the number of haemarthrosis episodes. However, there are still many aspects concerning the beneficial effects of RS that have not been quantified. A total of 156 radiosynovectomies (RS) were performed in 104 joints corresponding to 78 haemophiliacs (yttrium-90, rhenium-186). The mean patient age was 18 years. In another study involving the same group of patients, the parameters that improved most after RS were pain and haemarthrosis, followed by the World Federation of Hemophilia clinical score, muscle strength and range of movement (ROM). Following RS, improvement was seen to be independent of patient age, haemophilia type and grade, previous haematological treatment, the presence or absence of circulating inhibitor, synovial membrane size, the type of joint (elbow, knee and ankle), previous physical activity or lack of activity, the prior presence or absence of radiographic signs of joint degeneration (arthropathy) or the isotope used. RS is effective in treating haemophilic synovitis and may require 1-3 injections (RS-1, RS-2 and RS-3) spaced 6 months apart. Following RS-1, the knee had a 3.4- and 3.2-fold greater risk of not improving in terms of pain, compared with the elbow and ankle, respectively. Regarding ROM, lesser improvement was recorded after RS-1 in cases of severe haemophilia and the ankle. In other words, severe haemophilia implies a 2.1-fold greater risk of no improvement in ROM compared with mild and moderate haemophilia. In addition, the ankle presented a 6-fold greater risk of not improving in terms of ROM compared with the elbow and knee. RS affords effective treatment of chronic haemophilic synovitis. RS is effective in all patient groups, independently of the presence of circulating inhibitor antibody, the type of joint involved, the degree of synovial membrane hypertrophy and the presence of radiographic findings of joint degeneration (arthropathy).