Low-dose radiation therapy (LDRT) is gaining attention as a safe and noninvasive option for treating osteoarthritis (OA), particularly in patients who remain symptomatic despite standard therapies such as medications, physical therapy, and injections. The purpose of this review is to evaluate the efficacy, safety, and proposed mechanisms of LDRT in OA using recent evidence. A structured literature search of major medical databases was conducted, focusing on studies published within the past decade. A total of 23 sources were included, consisting of randomized controlled trials, retrospective cohort studies, and narrative reviews that assessed pain, function, and safety outcomes following LDRT. Overall, the majority of studies report clinically meaningful pain reduction, typically in the range of 20–50% improvement, along with improved joint function and quality of life. Response rates frequently exceeded 70% of treated joints, with benefits sustained over follow-up periods ranging from weeks to several months, and some studies demonstrating additional improvement after repeat treatment courses. Standard dosing regimens (3–6 Gy delivered in small fractions over 2–3 weeks) were consistently well tolerated, with minimal side effects and a very low estimated risk of radiation-related complications, particularly in older patient populations. While some randomized trials report mixed or neutral findings, these are often limited by small sample sizes, short follow-up durations, and variability in treatment protocols, whereas observational studies more consistently demonstrate positive outcomes. Evidence suggests that LDRT exerts anti-inflammatory and immunomodulatory effects, supporting its clinical benefit. Overall, the available evidence suggests moderate-quality support for LDRT as a promising, practical, and underutilized treatment option for OA, though further large-scale, well-designed randomized trials are needed to better define its optimal use in clinical practice.
