Evaluating the Efficacy of Low Dose Radiotherapy in the Treatment of Painful, Benign Musculoskeletal Conditions

Introduction: Inflammatory diseases of the locomotor system are a very heterogeneous group of ailments, including enthesopathies. They arise as a result of long-term overload in the area of tendon attachments, which may lead to chronic inflammation and then, degeneration, which are the cause of chronic pain. The main methods of treatment are physiotherapy, physical agents treatment, pharmacological and orthopaedic treatment, i.e. manual therapy, the use of appropriate insoles correcting posture defects, cryotherapy, shock waves, iontophoresis, non-steroidal anti-inflammatory drugs, steroid injections, surgery and platelet-rich plasma therapy. Another, lesser-known method of treatment is low-dose radiation therapy (LDRT).

Research objective: To evaluate the efficacy, time to improvement and analgesic effect duration after low dose radiotherapy (LDRT) in patients with enthesopathies.

Materials and methods: A retrospective analysis included a group of 90 patients (51 women, 39 men) with a diagnosis of enthesopathy and treated with conformal radiotherapy using photon radiation at the NIO in Kraków from July 2018 to April 2021. The treated group included patients with heel, elbow, knee, shoulder and wrist problems. In each case, the total dose of radiation was 6 Gy, divided into 6 fractions administered on subsequent working days, given in a vacuum form to the patient immobilised. Pain was assessed with the use of an 11-point numerical rating scale (NRS). Pain was assessed by implementing the above mentioned scale prior to the commencement of radiotherapy, during the treatment, and then 1 month and 6 months following the completion of treatment.

Results: In the vast majority of patients (92%), with a mean age of 51 years, at least temporary, partial improvement of pain has been demonstrated in the irradiated joints. The median time to treatment response was 30 days. Median pain intensity, as measured via the NRS scale, was 8.0 (IQR 7.0-10.0) before the treatment, 5.0 (IQR 3.0-7.0) after 1 month, and 2.0 (IQR 0-4.0) after 6 months from treatment completion. Persistent improvement in pain control after LDRT was shown in 85% of patients, with a mean follow-up period of 522 days (range: 55-952 days). The best response was observed in patients with heel spurs (a decrease of median NRS score by 7.0).

Conclusions: Low dose RT is a very effective method of pain reduction in enthesopathies, particularly among patients with heel spurs. Most patients experienced pain reduction as early as 1 month after LDRT. Continuous pain reduction was observed during the follow-up period up to the 6th month and in most cases, the analgesic effect was long-lasting.

