Low-Dose Radiation Therapy for Tendonitis

Low-dose radiation therapy (LDRT) is an outpatient treatment that directs a very small amount of radiation at an inflamed area, aiming to calm the inflammation that drives chronic pain. Tendonitis, including epicondylitis (commonly known as tennis elbow or golfer's elbow), is one of several tendon and soft-tissue conditions treated with LDRT, particularly in parts of Europe where this use has a long clinical history.

What the Evidence Shows

A prospective Swiss study followed patients over age 40 with epicondylitis, plantar fasciitis, or finger osteoarthritis whose pain had lasted through at least six months of conservative treatment. At follow-up visits up to 12 months after LDRT, patients with tennis elbow (lateral epicondylitis) had significantly less pain at rest and during activity and a stronger grip. Patients with golfer's elbow (medial epicondylitis) also had less pain and a stronger grip.^[1]

A German randomized trial of 199 patients with painful elbow syndrome compared two doses: six treatments of 0.5 Gy (3 Gy in total) or six treatments of 1.0 Gy (6 Gy in total). Responses were high in both groups, with 94% of all patients reporting a response at long-term follow-up, and there was no significant difference between the two doses. For radiation protection, the authors recommended that a course not exceed 3 Gy.^[2]

Radiation for tendon problems also has a long history. A review of radiotherapy for inflammatory conditions in the 1920s to 1940s, covering more than 37,000 patients across hundreds of studies, reported that conditions including tendonitis often responded with relief lasting months to years.^[3] Doses and equipment then were very different from today's.

Be aware: none of these studies compared LDRT with a sham treatment, so they cannot show how much of the improvement was due to the radiation itself.

Typical Schedule

• Total dose of about 3 to 6 Gy, depending on the program's protocol, split into 6 treatments
• Treatments given 2 to 3 times per week, over about 2 to 3 weeks
• Each visit takes roughly 10 to 15 minutes; no needle, sedation, or recovery period

Who May Be a Candidate

Programs generally consider adults with chronic tendonitis or epicondylitis who have already tried conservative treatments such as rest, bracing, physical therapy, or corticosteroid injections without lasting relief. The Swiss study above enrolled only patients over age 40. A radiation oncologist weighs age, duration of symptoms, and prior treatment history before recommending it.

References:
1. Rogers S, et al. Prospective Evaluation of Changes in Pain Levels, Quality of Life and Functionality After Low Dose Radiotherapy for Epicondylitis, Plantar Fasciitis, and Finger Osteoarthritis. Front Med (Lausanne). 2020;7:195. Full text
2. Ott OJ, et al. The Erlangen Dose Optimization trial for low-dose radiotherapy of benign painful elbow syndrome. Long-term results. Strahlentherapie und Onkologie. 2014. Article record
3. Calabrese EJ, et al. Radiotherapy treatment of human inflammatory diseases and conditions: Optimal dose. Hum Exp Toxicol. 2019. SAGE Journals