3522 - Low Dose Radiation Therapy (LDRT) for Osteoarthritis: A Retrospective Study of 59 Patients and 94 Joints Treated
Presenter(s)
N. Shah1,2, R. P. Bhandari1, R. Daniel3, A. Bagrova4, A. Grunbaum5, C. Faña-Souchet6, J. Henrietta Ablordeppey7, and A. Chopra1; 1Clearwater Radiation Oncology, Clearwater, FL, 2University of Florida, Gainesville, FL, 3Bay Area Rheumatology, Oldsmar, FL, 4BayCare Medical Group, Clearwater, FL, 5Gulf Coast Rheumatology, Trinity, FL, 6AMA Medical Group, Dunedin, FL, 7MyCare Medical, Clearwater, FL
Purpose/Objective(s): This retrospective study aims to examine the efficacy of Low Dose Radiation Therapy (LDRT) delivered via a linear accelerator on patients treated for osteoarthritis, measuring pain relief and improvements in mobility and functionality across various joints.
Materials/Methods: 59 patients and 94 affected joints were treated with LDRT between January 2023 and January 2025 at a radiation therapy institute. Each patient received 6 treatments of 0.5 Gy every other day, for a total of 3 Gy over the course of two weeks. Pain was documented using the numeric rating scale (NRS) prior to treatment and approximately four weeks post-treatment. Significant and complete improvement was defined as a decrease in pain on the NRS of greater than 20% and greater than 80% respectively. The mean age of patients was 75.3 (± 9.02) years, with 44% male and 56% female patients. The treated joints included: 45 hands (48%), 29 knees (31%), 10 shoulders (11%), 5 hips (5%), and 5 feet (5%).
Results: Following LDRT, 89% of patients showed significant improvement in pain relief and functionality. 66% of patients displayed complete improvement. The mean pain score prior to treatment was 7.27 (± 1.70), while after treatment it dropped to 1.84 (± 2.80) on the NRS scale (p <0.0001). Of the patients who reported an initial positive pain response during the first 4-week follow-up visit, 91% continued to experience significant improvement at 6 months. The patient with the longest reported relief in our study has been pain-free in her bilateral knees and bilateral hands for 14 months. Additionally, age (p=0.7892) and joint size (p=0.2872), whether small (hands, feet) or large (knees, hips, shoulders), were not found to significantly predict outcomes.
Conclusion: The use of LDRT in this retrospective study has been shown to be effective in treating osteoarthritis. Given that LDRT has been extensively shown to be safe and have limited side effects on patients, LDRT is a valuable non-invasive option for patients looking to improve pain and joint function. These results highlight LDRT as a viable emerging treatment option for osteoarthritis and emphasize the need for further research with prospective studies of larger cohort numbers.