Radiosynoviorthesis in People With Haemophilia—Pain‐Related and Clinical Outcomes: A Prospective Controlled Cohort Study

INTRODUCTION: Radiosynoviorthesis (RSO) may alleviate pain and clinical symptoms in people with haemophilia (PwH), however, controlled longitudinal data on these outcomes remain limited. AIM: To evaluate the effects of RSO on pain, joint health, swelling, and treatment satisfaction over twelve months. METHODS: Patients with an indication for RSO (n = 30) and patients without indication (n = 33) were examined for subjective joint-related pain (NRS), pressure pain thresholds (PPT), the Haemophilia Joint Health Score (HJHS), and joint swelling at baseline and three, six, and twelve months post-RSO. RSO-treated joints (J-RSO, n = 33) were compared to the corresponding contralateral joint (J-CL, n = 33), and joints of control PwH without RSO (J-Con, n = 33). RESULTS: RSO was administered in 9 elbows, 6 knees, and 18 ankles. Over the twelve-month follow-up, no significant time x joint group interaction was observed for NRS between J-RSO and J-Con (p = 0.092) or J-CL (p = 0.096). However, from baseline to three months, reduction in NRS was significantly more pronounced in J-RSO compared to control joints. No significant differences in longitudinal changes were observed for PPT or HJHS. Swelling was significantly reduced in J-RSO at three and six months (each p = 0.037), without significant differences compared to control joints. At twelve months, the majority of RSO-treated patients (78.8%) reported treatment satisfaction. CONCLUSION: RSO was associated with a greater early reduction in subjective joint-related pain. Over the twelve-month follow-up, this gradually decreased, resulting in no significant difference in overall pain trajectory. Swelling decreased for six months only in J-RSO, while PPT and HJHS showed no significant improvements in J-RSO.