American Radium Society (ARS) Appropriate Use Criteria (AUC) for Low-Dose Radiotherapy for Treatment of Osteoarthritis

OBJECTIVES: To summarize current evidence for radiotherapy in the treatment of OA. The population, intervention, comparator, and outcome questions included: What is the role of LDRT for treatment of OA?; What are risks of LDRT?; and What are the optimal RT techniques for OA? METHODS: This multispecialty-led committee includes radiation oncologists, rheumatologists, orthopedic surgeons, and a patient advocate. Using the population, intervention, comparator, outcome, timing and study design (PICOTS) framework, evidence regarding treatment outcomes was assessed using Cochrane and PRISMA methodology. Eligible studies included prospective and retrospective (n≥50) studies published between January 1, 2010, and May 10, 2025, from Embase, Medline, and PubMed databases. Study type and quality were assessed. Well-established RAND-UCLA consensus methodology (modified Delphi) was used to rate the appropriateness of the treatment options. RESULTS: Of the 548 articles identified using the search strategy, 44 were selected for inclusion. Eight additional studies were identified through backward citation searching. Ten well-designed studies accounting for biases, 15 moderately well-designed studies accounting for the most common biases, 18 studies with design limitations, 8 supplemental studies not useful as primary evidence, and 1 meta-analysis were included. Additional studies were included to provide context and were not used to guide recommendations. The results of this analysis demonstrate that LDRT results in an overall treatment response rate of 60% to 90%, with significant clinical benefits including pain reduction, increased joint mobility, and improved quality of life. CONCLUSIONS: This systematic review and consensus guidelines for LDRT treatment of OA are based on current evidence. Further high-quality studies are warranted.