Low-Dose Radiation Therapy for Osteoarthritis
Low-dose radiation therapy (LDRT) should not be used for osteoarthritis treatment, as the highest-quality randomized controlled trial found no benefit over sham treatment, and no major clinical practice guidelines recommend this intervention. 1
Evidence Against LDRT Use
Highest-Quality Study Shows No Benefit
The 2019 Dutch randomized, double-blinded, sham-controlled trial—the only high-quality RCT available—found that LDRT provided no advantage over sham treatment in patients with knee osteoarthritis who had failed standard therapies. 1
At 3 months post-intervention, 44% of LDRT patients versus 43% of sham patients met OMERACT-OARSI response criteria (difference 2%, 95% CI -25% to 28%), demonstrating no clinically meaningful effect. 1
LDRT showed no impact on pain, function, or any inflammatory markers assessed by ultrasound, MRI, or serum biomarkers compared to sham treatment. 1
Based on this definitive RCT and the absence of other high-quality evidence, the study authors explicitly advise against the use of LDRT as treatment for knee osteoarthritis. 1
Supporting Evidence Shows Methodological Weakness
A 2016 systematic review identified only seven studies on LDRT for osteoarthritis, all with retrospective uncontrolled observational designs and weak methodological quality. 2
The systematic review concluded there is insufficient evidence for efficacy or safety of LDRT in osteoarthritis treatment due to the absence of high-quality studies. 2
While a 2022 German trial (ArthroRad) reported pain relief with both 3.0 Gy and 0.3 Gy doses, it lacked a placebo control group and was closed prematurely due to slow recruitment, limiting its validity. 3
A 2025 Iranian study and 2022 Spanish case series reported positive results, but neither included sham controls, making placebo effects impossible to distinguish from true treatment effects. 4, 5
Absence of Guideline Support
Major evidence-based osteoarthritis guidelines—including EULAR recommendations, American College of Rheumatology guidelines, and comprehensive management protocols—do not mention or endorse LDRT as a treatment option. 6, 7
Current guidelines prioritize non-pharmacologic interventions (exercise, weight loss, education) and pharmacologic therapies (acetaminophen, topical NSAIDs, oral NSAIDs with gastroprotection, intra-articular corticosteroids) for which substantial evidence exists. 6, 7, 8
Recommended Evidence-Based Alternatives for Refractory Osteoarthritis
Non-Pharmacologic Core Treatments (Mandatory Foundation)
Joint-specific strengthening exercises and general aerobic conditioning must be implemented, as randomized trials demonstrate effect sizes of 0.57–1.0 for pain reduction with sustained improvements for 2–6 months. 6, 7
Weight loss for patients with BMI ≥25 kg/m² significantly reduces joint load and osteoarthritis symptoms. 7, 8
Patient education, assistive devices, shock-absorbing footwear, and local heat/cold applications provide essential symptom management. 6, 7
Pharmacologic Escalation Algorithm
Step 1: Acetaminophen up to 3,000 mg daily in divided doses (scheduled dosing superior to as-needed). 7, 8
Step 2: Topical NSAIDs (diclofenac or ketoprofen gel) applied to affected joints twice daily, with minimal systemic absorption and lower adverse-event risk than oral agents. 7, 8
Step 3: Intra-articular corticosteroid injection for moderate-to-severe pain with joint effusion, providing effective short-term relief (1–3 weeks) especially when oral NSAIDs are contraindicated. 7, 8
Step 4: Duloxetine 30 mg daily for one week, then 60 mg daily, conditionally recommended for osteoarthritis with neuropathic pain features. 7
Step 5: Oral NSAIDs at the lowest effective dose for the shortest duration, mandatory co-prescription with proton-pump inhibitor for gastroprotection, only after failure of above steps. 7, 8
Step 6: Short-course weak opioid (sustained-release tramadol) only after exhausting all other options, with slow upward titration; reserve as absolute last-line due to high toxicity and limited long-term benefit. 7, 8
Critical Safety Considerations
Never use glucosamine, chondroitin, or omega-3 supplements, as current evidence does not demonstrate efficacy for osteoarthritis. 7, 8
Elderly patients face substantially higher risks of gastrointestinal bleeding, renal insufficiency, and cardiovascular complications with oral NSAIDs; extreme caution or contraindication applies in renal insufficiency, heart failure, and cardiovascular disease. 6, 7
Acetaminophen should not exceed 4,000 mg daily, with a preferred limit of 3,000 mg in older adults to minimize hepatotoxicity risk. 7, 8
Why LDRT Fails the Evidence Standard
The fundamental problem with LDRT is that the only rigorous sham-controlled trial demonstrated no benefit, while all positive reports lack placebo controls and therefore cannot distinguish true therapeutic effect from placebo response. 1, 2 In contrast, the recommended alternatives above have Level 1 or Level 2 evidence from multiple randomized controlled trials demonstrating superiority to placebo for both pain reduction and functional improvement. 6, 7
Given the absence of guideline endorsement, the negative findings from the highest-quality controlled trial, and the availability of multiple evidence-based alternatives with proven efficacy, LDRT cannot be justified as an appropriate treatment option for osteoarthritis in clinical practice. 1, 2