Prospective evaluation of phosphorus-32 radiation synovectomy in patients with severe and chronic rheumatoid arthritis unresponsive to conventional medical treatment.

Objectives: To determine the efficacy of Phosphorus-32 radiation synovectomy in the treatment of patients with severe rheumatoid arthritis (RA) unresponsive to systematic or local medical therapy.

Methods: Twenty-three knees in 16 patients with severe chronic RA were prospectively treated by intra-articular installation of Phosphorus-32 and evaluated at 1, 3, 6, and 12 months. The Western Ontario and McMaster Universities Arthritis index (WOMAC), visual analog scale (VAS), Health Assessment Questionnaire (HAQ), pain scale, and grade of joint effusion and tenderness were assessed. At the 12-month time interval, the treated knees were classified into four categories: excellent response (no symptoms), good response (significant reduction of symptoms), moderate response (slight decrease), and poor response (no change or worsening).

Results: Excellent response or good response was observed in 13/23 (56.5%) of the treated knees, moderate response in 2/23 (8.7%) of the treated knees, and poor response in 8/23 (34.8%) of the treated knees. The grades of effusion and tenderness were significantly decreased one-month posttreatment (P< 0.05); however, these changes did not persist at other time intervals (P > 0.05). There was a significant improvement in the HAQ, WOMAC, VAS, and pain scores at all time points compared with baseline, including at the 12-month time interval (P < 0.05).

Conclusion: Phosphorus-32 radiosynovectomy is an effective therapeutic treatment for patients with RA of the knee unresponsive to conventional pharmacotherapy.