Comparison of the efficacy of radial and focused extracorporeal shock-wave therapy (ESWT) in myofascial pain syndrome: a randomized, sham-controlled study.

Abstract

Myofascial pain syndrome (MPS) is one of the most common pain syndromes characterized by painful trigger points. Active trigger points may cause spontaneous pain, reduce quality of life, and result in workforce loss. Extracorporeal shock-wave therapy (ESWT), using radial or focused acoustic waves created outside the body, is a treatment method used for musculoskeletal problems. In Focused ESWT (F-ESWT), the depth of the body part to be targeted can be adjusted. Penetration into the tissue is better than radial waves. Radial ESWT (R-ESWT) has a more superficial effect, and its spread in liquids with a density similar to tissues is half that of focused ESWT. Previous studies have shown that radial and focused ESWT waves applied to trigger points in the upper trapezius fibres reduce reflected and local pain in myofascial pain syndrome. The aim of this study was to compare the effectiveness of radial and focused ESWT types on trigger points in upper trapezius fibres in patients with myofascial pain syndrome. This prospective, randomized, sham-controlled study included 57 patients, randomly assigned to one of 3 groups. The patients underwent R-ESWT, F-ESWT and sham protocols for 4 sessions. Evaluations were made with a Visual Analog Scale (VAS) to assess pain, the Health Assessment Questionnaire (HAQ), and the Beck Depression Inventory (BDI) before treatment, post-treatment, then at 1, 3 and 6 months after completion of the treatment. Symptom duration was the only parameter that was significantly different between the groups before the treatment (p = 0.025). VAS scores improved after treatment compared to baseline for all groups (p < 0.05), with improvements continuing in the ESWT groups. The BDI and HAQ scores did not differ between the groups, and the F-ESWT group showed a significant improvement in BDI and HAQ (p < 0.01, p = 0.018, respectively). The VAS scores of the ESWT groups were similar and significantly higher than those of the sham group, but mid-long term changes did not differ across the groups (p = 0.065). In patients diagnosed with myofascial pain syndrome who underwent R-ESWT, F-ESWT and sham therapy on active trigger points in the upper trapezius fibres, an improvement in pain was observed in the R and F-ESWT groups even in the long term. While the improvement in pain scores was the same for the radial and focused types at all time points, the improvement in both was significantly higher compared to the sham application.