90Y Radiosynovectomy in Persistent Synovitis Caused by Knee Replacement: Long-Term Outcome. (January 2021)

• Record Type: Journal Article
• Authors: Liepe, Knut; Baehr, Marcel
• Is Part Of: Clinical nuclear medicine. Volume 46:Number 1(2021)
• Publication Date: 2021-01
• Subjects: radiosynovectomy -- 90Y -- knee replacement -- persistent synovitis -- long-term outcome; Nuclear medicine -- Periodicals; Radioisotope scanning -- Periodicals; Nuclear Medicine -- Periodicals; 616.07575
• DOI: 10.1097/RLU.0000000000003405
• Languages: English
• ISSNs: 0363-9762

Abstract

Abstract : Introduction: After knee replacement, therapy resistant, persistent synovitis is a common issue, which causes effusion and pain, and leads to loosing. It has been hypothesized that radiosynovectomy (RSO) is useful in these patients. Materials and Methods: A cohort of 55 patients with 57 knee replacements and persistent synovitis underwent RSO using 4.9 ± 0.24 mCi (182 ± 9 MBq) of 90 Y-citrate. The number of RSOs ranged from 1 to 4. Bone scans before and 3 months after every RSO were performed. Long-term follow-up ranged from 0.8 to 7.6 years with a mean of 23.2 months. For qualitative analysis, an established 4 steps scoring was used. For quantification, the uptake was determined within the 99m Tc-MDP scintigraphy blood pool phase before and after therapy. Results: Long-term response was in 27% with excellent, 24% good, 30% weak, and 20% no response. The duration of response was 12.0 ± 12.0 months (maximum, 54 months). In patients with repeated treatment, the effect after the first therapy was lesser than in patients who received a single treatment in total. However, 3 months after the last RSO, patients with repeated treatment showed a similar effectiveness than single treated patients. At the end of long-term follow-up, patients with repeated RSOs had a higher effectiveness at similar duration response. In bone scan, 65% of patients showed a reduction of uptake. When comparing subjective and objective response, 78% of patients showed a concordance in both symptoms and scintigraphy. Pilot histological analysis revealed that the synovitis is triggered by small plastic particles. Conclusions: We concluded that RSO is an effective therapy in patients with knee replacement and persistent synovitis with high long-term response. Repeated treatment leads to a stronger long-time response.