Expert Perspective: Low Dose Radiation Therapy and Osteoarthritis Pain

Despite revolutionary advances in therapeutics for many of the inflammatory rheumatic diseases, osteoarthritis (OA) has not been one of the diseases for which therapy has advanced dramatically, and OA pain frequently remains incompletely controlled. Low dose radiation therapy was commonly used to treat arthritis in the early twentieth century, but it lost currency in the latter years of that century and was not considered to be useful. However there has been a resurgence of interest in its potential utility for the treatment of refractory OA pain. In the last several years, many observational studies have been published suggesting that it may be useful for OA, and the German Society for Radiation Oncology has even disseminated guidelines for its use in OA. Concomitantly, radiation therapists across the United States have made presentations to rheumatology divisions about its availability for this indication and are recommending it for a multitude of patients with painful OA. Close examination reveals that the evidence base for such recommendations is sparse, and accumulating evidence suggests that this modality may not provide incremental benefit over placebo, whereas the placebo effect itself is so potent in OA that it is reasonable to consider the placebo itself as "active" therapy. Unless further evidence is developed through randomized double-blind controlled trials (RDBCTs), rheumatologists should be circumspect about suggesting it for their patients. This Expert Perspective will explore the history of this modality and the data surrounding its use in OA and will provide an evaluation of its potential utility for relieving OA pain.