Osteoarthritis (OA) is one of the most common etiological causes of chronic joint pain and functional limitation worldwide. The disease is characterized by progressive degeneration of the articular cartilage, chronic inflammation, and the resulting restriction of movement. As the population continues to age, the prevalence of osteoarthritis is steadily increasing, exerting a substantial impact both on patients’ quality of life and on the burden placed on healthcare system resources.

Standard treatment approaches include physiotherapy, non-steroidal anti-inflammatory drugs, intra-articular injections, and, in severe stages of the disease, joint replacement surgery. However, these methods are not sufficiently effective in every patient group, which has led to a marked increase in scientific interest, in recent years, in low-dose radiotherapy (LDRT) as an additional therapeutic option for managing chronic pain [1,6].

Low-Dose Radiotherapy and Its Mechanism of Action

LDRT is a non-oncological radiotherapy method whose therapeutic target is the modulation of the inflammatory process and the reduction of pain. Unlike oncological radiotherapy, which employs doses of 45–70 Gy, LDRT is administered at 0.5–1 Gy per fraction, with a total cumulative dose of 3–6 Gy [1].

Existing studies have confirmed that low-dose ionizing radiation reduces the synthesis of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6), suppresses macrophage activity, inhibits the NF-κB signaling pathway, and increases the activity of the anti-inflammatory cytokine IL-10 in particular. The combination of these biological changes results in a reduction of inflammation and pain intensity and an improvement in joint function[4–6].

Clinical Studies

Low-dose radiotherapy has been used in clinical practice for many years, predominantly in Germany, Austria, and other European countries. The 2015 guideline of the German Society for Radiation Oncology (DEGRO) considers LDRT to be recommended for patient groups in whom conservative treatment has proven ineffective; the recommended dosing regimen is 0.5–1 Gy per fraction, with a total dose of 3–6 Gy (Ott et al., 2015 [1]).

In 2016, a systematic review by Minten and colleagues showed that, in the majority of the studies examined, LDRT was associated with pain reduction and improved joint function, although the authors noted the need for randomized studies of higher methodological quality [2].

In 2025, a comprehensive review by Hoveidaei and colleagues confirmed that LDRT is particularly effective in patient populations in whom pharmacological and physiotherapeutic treatment failed to provide sufficient clinical benefit. According to the authors’ observations, the clinical effect typically develops gradually over the course of several weeks and may be sustained for a period ranging from several months up to one year [3].

In 2026, the multidisciplinary American Radium Society (ARS) working group concluded, on the basis of a systematic analysis of 44 clinical studies, that the overall clinical response rate following LDRT reaches approximately 60–90%. Pain reduction, improved joint mobility, and increased quality of life were observed in the majority of patients; however, the working group explicitly emphasized the necessity of additional randomized studies of higher methodological quality (Dove et al., 2026) [5].

Safety and Limitations

One of the essential advantages of LDRT is its low toxicity — the doses used are considerably lower than those employed in oncological radiotherapy. Existing data indicate that the treatment is well tolerated and that acute adverse events are rare. The theoretical risk of developing a secondary malignant neoplasm is considered low, particularly in the elderly patient population [2,5,6].

Despite the existing favorable data, LDRT is not currently regarded as a first-line treatment method for osteoarthritis. This is due to the fact that a portion of the existing studies are retrospective in nature, and some have been conducted on relatively small patient cohorts — circumstances that underscore the need for additional multicenter, randomized, placebo-controlled trials [2,3,5].

Current Situation in Georgia

Linear accelerators currently operating in Georgia are used mainly for the radiotherapeutic treatment of malignant neoplasms. Low-dose radiotherapy, as a tool for managing osteoarthritis and other benign degenerative-inflammatory conditions, has not yet been introduced into clinical practice in the country, and no corresponding national clinical guidelines exist [1,5].

The conduct of local clinical studies, systematic evaluation of treatment outcomes, and multidisciplinary collaboration among radiotherapists, orthopedists, and rheumatologists will, in the future, facilitate an objective assessment of the efficacy and safety of LDRT and help determine its potential integration into Georgia’s healthcare system.

Conclusion

Current scientific evidence indicates that low-dose radiotherapy represents a safe and promising adjunctive method for the management of chronic joint pain. Its anti-inflammatory action contributes to pain reduction, improved joint function, and enhanced quality of life, particularly in patient groups for whom conservative treatment is insufficient. At the same time, the widespread clinical implementation of LDRT requires additional studies of high methodological quality, the results of which will ultimately determine its place within the contemporary clinical strategy for managing osteoarthritis [1–5].

Author: Nata Toidze – Radiation Oncology Resident, MD

References

1. Ott OJ, Niewald M, Weitmann HD, Jacob I, Adamietz IA, Schaefer U, Keilholz L, Heyd R, Mücke R; German Cooperative Group on Radiotherapy for Benign Diseases (GCG-BD). DEGRO guidelines for the radiotherapy of non-malignant disorders. Part II: Painful degenerative skeletal disorders. Strahlenther Onkol. 2015;191(1):1-6. doi:10.1007/s00066-014-0757-3.
2. Minten MJM, Mahler E, den Broeder AA, Leer JWH, van den Ende CHM, van den Bemt BJF. The efficacy and safety of low-dose radiotherapy on pain and functioning in patients with osteoarthritis: a systematic review. Rheumatology International. 2016;36(1):133-142. doi:10.1007/s00296-015-3337-7.
3. Hoveidaei A, Karimi M, Salmannezhad A, Tavakoli Y, Taghavi SP, Hoveidaei AH. Low-dose Radiation Therapy (LDRT) in Managing Osteoarthritis: A Comprehensive Review. Current Therapeutic Research – Clinical and Experimental. 2025;102:100777. doi:10.1016/j.curtheres.2025.100777.
4. Khakshour E, Shobeiri SS, Koneru BN, et al. Low-dose radiotherapy in osteoarthritis: a comprehensive review of immunological and molecular mechanisms. International Journal of Radiation Biology. 2026;102(5):447-454. doi:10.1080/09553002.2026.2636290.
5. Dove A, Koneru B, Small W Jr, et al. American Radium Society Appropriate Use Criteria for Low-Dose Radiotherapy for Treatment of Osteoarthritis. American Journal of Clinical Oncology. 2026. doi:10.1097/COC.0000000000001333.
6. Seegenschmiedt MH, Micke O, Muecke R. Radiotherapy for non-malignant disorders: state of the art and update. Strahlenther Onkol. 2015;191:541-550.