Comparison of the Efficacy of Radial and Focused Extracorporeal Shock-wave Therapy (ESWT) in Myofascial Pain Syndrome: Prospective, Randomized, Sham Controlled Study

Myofascial pain syndrome (MPS) is a syndrome characterized by painful trigger points on palpation located at certain points of common muscles of the musculoskeletal system. Pain on palpation tends to radiate and is sometimes even accompanied by sensory symptoms (such as paresthesia) or autonomic findings (piloerection, sweating, etc.). Trigger points can be either latent or active. Active trigger points may cause spontaneous pain, while latent trigger points are more commonly manifested as pain radiating with palpation. Latent trigger points tend to turn into active trigger points as a result of acute stresses, microtraumas or postural disorders, and the trapezius muscle is the most common muscle in which myofascial trigger points are seen. Myofascial pain syndrome can cause many consequences such as disturbances in daily living acitivities, decrease in quality of life and loss of work force. It can also accompany anxiety and depression . Pharmacological therapy can be used in the treatment, since stretching exercises, dry needling, acupuncture or physical therapy modalities are another effective treatment options for patients who are not willing to use drugs or have co-morbidities .

Extracorporeal shock-wave therapy (ESWT) is a kind of physical therapy method performed with the help of acoustic waves created outside the body. It is frequently used in musculoskeletal conditions. Its effectiveness has been demonstrated in disorders such as calcaneal spur, lateral epicondylitis, calcific tendinitis, myofascial pain syndrome, and fibromyalgia .

Radial or focused waves are commonly used in application of ESWT. In Focused ESWT (F-ESWT), the depth of the body part to be injured can be adjusted. Thus, penetration into the tissue is better than radial waves. Radial ESWT (R-ESWT), on the other hand, has a more superficial effect, and its spread in liquids with a density similar to tissues is half that of F-ESWT . However some side effects were identified during the ESWT procedure, both wave types are thought to be safe and widely used.

It has been shown in previous studies that radial and focused ESWT waves applied to trigger points in the upper trapezius fibers reduce reflected and local pain in myofascial pain syndrome. The effectiveness of these waves has been evaluated in studies many times but the effectiveness of the two wave types has not been compared in patients with trigger points in the trapezius upper fibers in myofascial pain syndrome. The aim of this study is to compare the efficacy of R-ESWT and F-ESWT types on trigger points in trapezoidal upper fibers in myofascial pain syndrome.

This prospective, sham-controlled and double-blind study was carried out at Ankara Bilkent City Hospital, Physical Medicine and Rehabilitation Hospital. Fifty nine male and/or female patients enrolled the study initially. The study protocol is compatible with Helsinki declaration and approved by Ankara Bilkent City Hospital Ethics Committee (Approval number: E2-22-3033). Written and oral informed consents were obtained from the participants before allocation.