Low-dose radiotherapy of osteoarthritis: from biological findings to clinical effects-challenges for future studies

Comparative effectiveness of kilo- and megavoltage energies in low-dose radiotherapy for painful degenerative musculoskeletal diseases: a systematic review and meta-analysis

PURPOSE

This study aimed to assess the impact of different energy levels on the effectiveness of low-dose radiotherapy (LDRT) for treating painful degenerative musculoskeletal diseases, as comparative efficacy data are currently lacking.

METHODS

A systematic review was conducted in PubMed, Embase, and the Cochrane Library databases to identify studies with response information on the energy used (kilovoltage [kV] vs. megavoltage [MV]). The primary endpoint was the overall response rate (ORR), and the secondary endpoint was the complete response rate (CRR). Exploratory subgroup analyses included treatment site, study period, study design, country, and dose per fraction.

RESULTS

A total of 33 studies involving 12,143 patients were analyzed. Short-term follow-up (up to 6 months) showed a pooled ORR of 64% (95% CI 46-78%) for kV and of 62% (95% CI 54-70%) for MV. Long-term follow-up (at least 12 months) revealed a pooled ORR of 85% (95% CI 65-95%) for kV and of 69% (95% CI 62-75%) for MV. Subgroup analysis indicated no significant differences in ORR for energy level stratified by treatment site and other factors. Regarding dose per fraction (0.5 Gy vs. 1.0 Gy), comparable ORRs were demonstrated between the two energies. No clinical side effects were noted.

CONCLUSION

This meta-analysis suggests that the known effectiveness of LDRT in painful degenerative musculoskeletal disease may not depend on the energy used. Additional studies using standardized evaluation methods are warranted to establish consistency and enhance the comprehensiveness of research. Further research is also needed to explore treatment modality selection considering disease-specific biology.

Radiotherapy for painful shoulder syndrome: a retrospective evaluation

PURPOSE

We evaluated the efficacy of low-dose radiotherapy for painful shoulder syndrome from an orthopedic perspective.

METHODS

Patients with painful shoulder syndrome were recruited for this retrospective clinical quality assessment from January 2011 to December 2017. Patients were treated with a linear accelerator or an orthovoltage device at individual doses of 0.5-1.0 Gy and total doses of 3.0-6.0 Gy. To assess response, we used the von Pannewitz score with five levels: "worsened," "unaffected," "improved," "significantly improved," and "symptom free." "Good treatment success" was defined as "significantly improved" and "symptom free." Within-group and between-group differences were statistically evaluated.

RESULTS

Of 236 recruited patients (150 women, 86 men; mean age 66.3 [range 31-96] years), 180 patients underwent radiotherapy with a linear accelerator and 56 with an orthovoltage device. Fractionation was 12 × 0.5 Gy in 120 patients, 6 × 0.5 Gy in 74, and 6 × 1 Gy in 42 patients. Treatments were completed in one series for 223 and in two series at least 6 weeks apart for 13 patients. Of the 236 patients, 163 patients (69.1%) agreed to be re-interviewed at a median of 10.5 (range 4-60) months after radiotherapy completion. Directly after radiotherapy, 30.9% (73 patients) had "good treatment success," which had increased to 55.2% (90 patients) at follow-up.

CONCLUSION

Protracted pain improvement with low-dose radiotherapy is possible in painful shoulder syndrome. Patients with refractory pain because of subacromial syndrome or shoulder osteoarthritis should also be evaluated for radiotherapy.

Implementing a low-dose radiation therapy program for musculoskeletal pain disorders: tips, tricks, and essentials for clinical researchers

INTRODUCTION

Painful musculoskeletal disorders (PMDs) represent an increasing public health concern, particularly among aging populations. When conservative therapies prove insufficient, low-dose radiotherapy (LDRT) has emerged as a non-invasive and effective treatment alternative. Despite growing clinical evidence supporting its efficacy, LDRT remains underutilized due to persistent skepticism and the absence of standardized clinical guidelines.

MATERIALS AND METHODS

This review synthesizes current evidence on the use of LDRT for PMDs, focusing on its biological mechanisms, optimal dosing regimens, clinical efficacy, and safety profile. Attention is given to dose fractionation strategies, timing of re-irradiation, and technological advancements that enhance treatment precision.

RESULTS

LDRT provides pain relief in 60-90% of treated cases, with the most favorable results achieved using fraction doses between 0.3 and 0.7 Gy. Its anti-inflammatory effects are mediated through immune modulation, reduced proinflammatory cytokine expression, and promotion of tissue repair. Re-irradiation performed 10-12 weeks after the initial cycle may be beneficial in patients experiencing symptom persistence or recurrence. Long-term follow-up data confirm sustained efficacy and indicate a minimal risk of radiation-induced malignancies in older adults.

CONCLUSION

LDRT is a safe and effective treatment option for PMDs, especially in patients unresponsive to conventional therapies. To facilitate its broader adoption, this review underscores key clinical evidence and proposes practical considerations for integrating LDRT into multidisciplinary pain management protocols.

Effects of low dose rate radiotherapy on pain relief, performance score, and quality of life in patients with knee osteoarthritis; a double-blind sham-controlled randomized clinical trial

INTRODUCTION

Knee osteoarthritis (OA) is a prevalent chronic condition characterized by progressive damage to the articular cartilage, resulting in chronic pain, swelling, and reduced range of motion with a range of prevalence of 10-40%. This study aims to investigate the efficacy of low-dose radiation as a local treatment option for knee OA symptoms.

METHODS

In this prospective study, patients with confirmed OA and older than 65 years were randomly assigned to treatment and control groups. The protocol plan IRCT20160706028815N6 was registered in Iranian registry of clinical trials system. The treatment group received 3 Gy radiation over six fractions, while the control group continued routine treatment without radiation. The pain intensity and functional levels were assessed at pretreatment and each month following completion of therapy for six consecutive months by Visual Analog Scale (VAS) and the Lysholm 100-point Scale, respectively. Analgesic medication usage and performance status (PS) were also assessed.

RESULTS

The mean age of the patients was 77 years (range 72-89). All variables including VAS pain score, Lysholm scale, PS and analgesic consumption were improved following radiation from first month to the end of assessments (p value <0.01).

CONCLUSION

Results showed significant pain score improvements and enhanced joint function with no adverse effects. Findings were compared with previous studies, revealing mixed conclusions on low dose radiation therapy (LDRT) efficacy. Mechanistic hypotheses suggest LDRT may modulate inflammatory pathways. The study suggests LDRT at 3 Gy could benefit knee osteoarthritis patients and calls for further research on mechanisms of action in early-stage osteoarthritis.

The Controversial Late Effect of Shoulder Radiation Therapy in a Small Case Series

Introduction

Radiodermatitis is a common complication experienced by patients undergoing radiation therapy. Its severity can vary from mild erythema to more serious conditions, including desquamation, ulceration, and, in extreme cases, necrosis. In addition, it is widely acknowledged that radiotherapy (RT) itself carries oncogenic risks, potentially causing cellular mutations that may lead to the development of neoplasms, sometimes years after treatment. Diagnostic and staging tools such as magnetic resonance imaging, computed tomography, and positron emission tomography scans are crucial in these cases, with biopsy serving as the definitive method for histological confirmation. However, large excisions often required in these situations necessitate complex reconstructive procedures and are associated with a high risk of local complications, including wound dehiscence and infection.

Case Report

We present three cases of radiodermatitis that developed following radiation therapy to the shoulder. These cases highlight the need to consider radiodermatitis as a differential diagnosis for skin changes occurring after RT, especially in patients with a history of cancer.

Conclusion

The misdiagnosis or delayed diagnosis of radiodermatitis can substantially increase patient morbidity. Greater awareness of this potential complication underscores the importance of closely monitoring for skin-related issues in patients receiving RT.

Low-dose Radiation Therapy (LDRT) in Managing Osteoarthritis: A Comprehensive Review

Osteoarthritis (OA) is the most common degenerative arthropathy, impacting the quality of life for millions worldwide. It typically presents with chronic pain, stiffness, and reduced mobility in the affected joints. Nonsurgical treatments like physiotherapy or pharmacotherapy may provide limited relief and may have adverse effects and complications. Recently, low-dose radiation therapy (LDRT) has emerged as a potential alternative for managing OA, utilizing its anti-inflammatory effects. LDRT's anti-inflammatory effects involve modulating immune responses, reducing pro-inflammatory cytokines, and inducing apoptosis in inflammatory cells. Clinical studies show varying degrees of symptom relief, with some patients experiencing pain reduction and improved joint mobility while others show minimal response. The variability in LDRT treatment designs, radiation dosages, and patient populations complicates standardized treatment protocols and raises concerns about potential carcinogenic risks. Despite these issues, LDRT shows promise as an alternative to other OA treatments, especially for patients who don't respond to other treatments. This review aims to provide updated information on the effectiveness, mechanisms, and safety of LDRT in treating OA. We reviewed the literature of studies on the safety and efficacy of LDRT on affected joints by OA, its biological effects, potential therapeutic and adverse effects, application and contraindications, clinical outcomes, and clinical evidence in subjects with OA.

Effect of local mud application in patients with knee osteoarthritis - A systematic review and meta-analysis

Mud therapy is a safe, cost-effective approach for Knee Osteoarthritis (OA), promoting healing through warmth and minerals, providing pain relief, and improving function. The main objective of the current review is to assess the effectiveness of local mud application for pain management in patients with Knee OA. The published papers were obtained from PubMed, Embase, Scopus, Cochrane Library, ClinicalTrails.gov, Web of Science, and references from relevant systematic reviews from 1990 January to February 2023. Trials meeting the predefined criteria were included in this meta-analysis. The main focus of this study was to assess pain as a primary outcome measure. R software version 4.3.1 and Cochrane Risk of Bias Tool 1 were used to derive meta-analysis and risk of bias in the included studies. A meta-analysis was performed using the fixed-effects model to obtain a summary of treatment effects, which calculated the effect size (standardized mean difference; SMD) along with a 95% Confidence Interval (CI).In the current meta-analysis, a total of ten studies with 560 Knee OA patients were included. Findings demonstrated significant effects of local mud application on pain (SMD: -0.36, 95% CI: -0.56, -0.16), and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scale (SMD: -0.49, 95% CI: -0.68, -0.29) for individuals suffering from Knee OA. The current study identified compelling evidence to support the recommendation of mud application as an effective intervention for individuals with Knee OA. While local mud application may serve as a supplementary therapy alongside conventional medical approaches for improved Knee OA management, additional high-quality randomized controlled trials are required to validate these findings.

Low-dose radiotherapy for greater trochanteric pain syndrome-a single-centre analysis

PURPOSE

To determine predictive factors associated with a good response (GR) to and efficacy of low-dose radiotherapy (LDRT) in patients with greater trochanteric pain syndrome (GTPS).

METHODS

Patients with GTPS were irradiated on a linear accelerator with 0.5-1.0 Gy per fraction to a total dose of 3.0-4.0 Gy per series. The endpoint was subjective good response (GR) to treatment 2 months after completion of the last LDRT series, defined as complete pain relief or marked improvement assessed using the von Pannewitz score. A positive response to steroid injection (SI) was defined as pain relief of at least 7 days. Patient and treatment-related characteristics were evaluated with respect to LDRT outcomes.

RESULTS

Outcomes were assessed for 71 peritrochanteric spaces (PTSs; 65 patients, 48 females, with mean age of 63 [44-91] years). Prior SI had been given to 55 (77%) PTSs and 40 PTSs received two series of LDRT. Two months after completion of LDRT, GR was reported in 42 PTSs (59%). Two series of LDRT provided a significantly higher rate of GR than one series (72.5 vs. 42% PTSs, p = 0.015). Temporary pain relief after prior SI predicted GR to LDRT compared with PTSs which had not responded to SI (73 vs. 28% PTSs, p = 0.001). A regional structural abnormality, present in 34 PTSs (48%), was associated with a reduction of GR to LDRT (44 vs. 73% PTSs, p = 0.017).

CONCLUSION

LDRT is an effective treatment for GTPS. Administration of two LDRT series, prior response to SI, and absence of structural abnormalities may predict significantly better treatment outcomes.

ArthroRad trial: randomized multicenter single-blinded trial on the effect of low-dose radiotherapy for painful osteoarthritis-final results after 12-month follow-up

OBJECTIVE

Updated report about the randomized comparison of the effect of radiotherapy on painful osteoarthritis (OA) applying a standard dose vs. a very low dose regime after a follow-up of 1 year.

PATIENTS AND METHODS

Patients presenting with OA of the hand/finger and knee joints were included. After randomization (every joint region was randomized separately) the following protocols were applied: (a) standard arm: total dose 3.0 Gy, single fractions of 0.5 Gy twice a week; (b) experimental arm: total dose 0.3 Gy, single fractions of 0.05 Gy twice a week. The dosage was blinded for the patients. For evaluation the scores after 1‑year visual analog scale (VAS), Knee Injury and Osteoarthritis Outcome Score-Short Form (KOOS-PS), Short Form Score for the Assessment and Quantification of Chronic Rheumatic Affections of the Hands (SF-SACRAH) and 12-item Short-Form Health Survey (SF-12) were used (for further details: see [1]).

RESULTS

The standard dose was applied to 77 hands and 33 knees, the experimental dose was given to 81 hands and 30 knees. After 12 months, the data of 128 hands and 45 knees were available for evaluation. Even after this long time, we observed a favorable response of pain to radiotherapy in both trial arms; however, there were no reasonable statistically significant differences between both arms concerning pain, functional, and quality of life scores. Side effects did not occur. The only prognostic factor was the pain level before radiotherapy.

CONCLUSIONS

We found a favorable pain relief and a limited response in the functional and quality of life scores in both treatment arms. The possible effect of low doses such as 0.3 Gy on pain is widely unknown.

An introduction to low dose radiation therapy for shoulder osteoarthritis

Osteoarthritis (OA) is a painful, degenerative disease that affects the tissues of the joint spaces, such as the shoulder. Conventional medical treatment options, such as corticosteroid injections and anti-inflammatory medications, are not always sufficient to alleviate the symptoms from this disease. Low dose radiotherapy is a newer treatment option for patients with shoulder osteoarthritis and has shown positive outcomes. However, the problem is that there is a paucity of literature about treatment planning considerations for this new treatment option. The purpose of this case study was to provide an example of treatment planning techniques and considerations for shoulder osteoarthritis. Treatment techniques for shoulder LDRT, such as treatment field borders, prescribed dose, beam arrangements, appropriate beam energy, and special considerations are discussed.