The International Organisation for Radiotherapy for Benign Conditions (IORBC) acknowledges ongoing debates surrounding Low-Dose Radiotherapy (LDRT) for osteoarthritis while emphasizing critical limitations in the VA guidelines' evidence base. The VA's cautious stance relies heavily on limited sources: a  systematic review incorporating only 7 single-arm studies (most recent from 2015), two Dutch RCTs (2018-2019) comparing 6 Gy LDRT to sham therapy for hand/knee OA, and three single-arm studies. Crucially missing from this review are two positive RCTs demonstrating significant pain reduction in early-stage knee OA and German registry data with over 18,000 cases showing 63-90% symptom relief.

Particularly significant is the omission of two methodologically robust international trials. The Iranian double-blind, sham-controlled RCT (2025) administered 3 Gy total dose over six fractions to knee OA patients over 65, with monthly assessments through 6 months using validated pain and function metrics. This trial demonstrated statistically significant improvements (p<0.01) across all parameters beginning from the first month with no adverse effects.

Also compelling is Makarova et al.'s landmark Russian study following 292 knee OA patients for 9-10 years. This trial strategically included only early-stage disease (KL 0-2) and showed dramatic long-term benefits: 9.5% disability rate in the LDRT group (4.5 Gy total) versus 17.8% in the control group (HR=0.49), with adjusted analysis showing even stronger protection (HR=0.24). The LDRT intervention reduced knee replacement surgery by approximately two-thirds and could potentially prevent 25% of disability cases in this population.

The VA's negative conclusions stem primarily from small Dutch trials that have been criticized for significant design limitations when compared to modern protocols. These trials included patients with advanced osteoarthritis (56-61% had KL grade ≥2) whereas contemporary approaches target KL 1-3 cases only.  Additionally, radiation dosing differed substantially, with Dutch trials using 6 Gy total (1 Gy/fx) compared to modern protocols employing 3 Gy total (0.5 Gy/fx).

These methodological disparities highlight why the VA guidelines may not adequately reflect the current state of LDRT treatment. Modern approaches, with their refined patient selection criteria, optimized dosing protocols, and rigorous outcome tracking, represent a significant advancement over the studies upon which the VA based its recommendations.

The IORBC contends that updated evidence, particularly from recent positive RCTs with both short-term and long-term follow-up data and large registry datasets, provides compelling support for LDRT's efficacy when appropriately administered to suitable candidates under contemporary protocols.

If you would like to see the IORBC's President, Dr Richard Shaffer, present our critique on video, please follow the link: Richard Shaffer IORBC critique on VA's Systemic Review on LDRT for Osteoarthritis

If you would like to access and share a copy of the PDF document of this letter, please follow the link: IORBC Critique Regarding the VA Systemic Review on
Low-Dose Radiotherapy for Osteoarthritis