Characterization of the ideal candidate for knee radiosynoviorthesis treatment in patients with rheumatoid arthritis

OBJECTIVES: (1). To identify the main parameters that positively influence the outcome of knee radiosynoviorthesis (RSO) in patients with rheumatoid arthritis (RA) and (2). to determine the ideal candidate for this procedure. METHODS: We considered 80 knees (in 57 patients) that had undergone follow-up for at least 5 years and/or prosthesis implantation after RSO treatment. The parameters evaluated included age, gender, oligo-articular or polyarticular involvement, disease progression, radiological joint damage (Larsen scale), instability and/or axial deviation, body mass index (BMI), and psychological motivation for prosthesis implantation. RESULTS: Knee Larsen stage IV, presence of instability-axial deviation, disease progression, psychological motivation to the surgical replacement and BMI higher than the 85th percentile were associated with a negative outcome for RSO (prosthesis implantation). CONCLUSIONS: The ideal candidate for the RSO treatment is a patient with a low Larsen stage, no instability and/or axial deviation and a BMI below the 85th percentile. A patient's psychological motivation for the treatment should be evaluated before the RSO procedure.