(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.
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.
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).
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.