2026 Appropriate Use Criteria for Osteoarthritis Radiotherapy

Short answer: In 2026, the American Radium Society (ARS) published multidisciplinary appropriate use criteria for low-dose radiotherapy in osteoarthritis. The panel concluded that it can be an evidence-based option in selected situations, while also emphasizing the need for more high-quality studies. Appropriate use criteria guide decisions; they do not prove that treatment works for every patient.

What are appropriate use criteria?

Appropriate use criteria combine published evidence with structured expert voting to rate when a test or treatment may be reasonable. They are not:

• a guarantee of benefit;
• a substitute for individual evaluation;
• an FDA approval decision;
• an insurance coverage policy; or
• the same as a phase 3 trial result.

The ARS panel included radiation oncologists, rheumatologists, orthopedic surgeons, and a patient advocate. It used Cochrane and PRISMA methods to review studies and a modified RAND-UCLA Delphi process to rate scenarios.

What evidence did the panel review?

The search covered studies published from 2010 through May 10, 2025. Of 548 identified articles, 44 met inclusion criteria, with eight more found through references.

The panel classified:

• 10 studies as well designed with attention to bias;
• 15 as moderately well designed;
• 18 as having design limitations;
• eight as supplemental rather than primary evidence; and
• one meta-analysis.

This mix is important. A large evidence base can still contain substantial differences in methods and reliability.

What response did the review report?

The ARS publication reports overall treatment response rates of 60% to 90%, including pain reduction, improved mobility, and quality-of-life gains.

That range should not be presented as “your chance of success.” Studies define response differently, treat different joints, enroll different age groups, and use different doses and follow-up periods. Retrospective reports are also more vulnerable to selection and placebo effects than blinded randomized trials.

What does appropriate patient selection consider?

A clinical discussion may include:

• confidence that osteoarthritis is causing the symptoms;
• imaging severity and physical findings;
• age and expected lifetime radiation risk;
• prior physical therapy, activity modification, medication, braces, or injections;
• whether surgery is appropriate, desired, or medically feasible;
• the joint's location and nearby sensitive tissue;
• pregnancy status or potential;
• prior radiation exposure; and
• the person's goals and understanding of uncertainty.

Low-dose radiotherapy is generally discussed as a conservative option for persistent symptoms, not as a way to regrow cartilage or reverse structural arthritis.

What treatment schedules are discussed?

Contemporary reviews commonly describe total doses around 3 to 6 Gy, delivered in small fractions over roughly two to three weeks. A frequently used regimen is 0.5 Gy for six treatments, totaling 3 Gy.

Dose and technique should be selected by a radiation oncologist. More radiation is not automatically more effective, and an additional course should not be assumed without reassessment.

Why does uncertainty remain?

Some randomized sham-controlled trials found no meaningful advantage, while observational studies and the 2025 Korean randomized trial reported benefit in selected patients. A 2025 meta-analysis found no significant pain or function advantage over sham and recommended that treatment remain investigational or reserved for select refractory cases.

Differences may involve:

• patient selection;
• disease stage;
• radiation dose;
• treated joint;
• allowed pain medication;
• outcome definitions; and
• length of follow-up.

The ARS authors explicitly concluded that further high-quality studies are warranted.

How should a patient use the guideline?

The criteria can support a more informed consultation. Ask:

1. Which scenario in the criteria resembles my situation?
2. What standard options remain?
3. Which evidence supports treatment of this specific joint?
4. How will improvement be measured?
5. What risks matter at my age?
6. What happens if symptoms do not improve?

The most responsible reading of the 2026 criteria is neither “radiation never helps arthritis” nor “radiation works 90% of the time.” It is that low-dose radiotherapy may be appropriate for selected patients after a balanced review of evidence, alternatives, and risk.

Questions patients often ask

Is an appropriate use criterion the same as FDA approval?

No. It is an expert consensus tool based on a structured evidence review. It does not mean the FDA approved a specific osteoarthritis radiation indication or guarantee insurance coverage.

Do the criteria prove a 60% to 90% success rate?

No. That range summarizes responses across heterogeneous studies with different joints, patients, methods, and endpoints. It should not be used as an individual prediction.

Does the guideline recommend low-dose radiotherapy before physical therapy or medication?

Patient selection generally considers established conservative options first. Exact sequencing should be individualized with the clinicians managing the joint condition.

Sources and further reading

1. American Radium Society Appropriate Use Criteria for Low-Dose Radiotherapy for Osteoarthritis. American Journal of Clinical Oncology (2026).
2. Low-Dose Radiotherapy for Osteoarthritis: Current Evidence, Practical Recommendations and Future Perspectives. Seminars in Radiation Oncology (2026).
3. Efficacy, safety, and pain management of low-dose radiation therapy in osteoarthritis. Rheumatology International (2025).