Radial Shock Wave and Acupuncture for Myofascial Pain

Myofascial pain syndrome is common in Rehabilitation clinic. The pain occurs asymmetrically in isolated or regional muscles, and is associated with acute muscle strain or chronic muscle overuse. Myofascial pain is characteristics with localized muscle tenderness, palpable intramuscular taut band, typical referred pain, and local twitch response.

Treatment of myofascial pain syndrome includes physical therapy, stretch exercise, dry needle insertion and trigger point injection. Acupuncture originated from ancient Chinese medicine which involves the insertion of fine needle to stimulate specific points of the body along the 12 meridians. The mechanism of pain relief may be initiated by activation of both spinal segmental and supraspinal centers. Acupuncture is commonly used for pain relief.

Recently, radial shock wave has been shown to be effective in the treatment of chronic musculoskeletal pain, including calcific tendinitis, epicondylitis, and plantar fasciitis. The energy and pressure produced by radial shock wave is focused on the treated musculoskeletal tissue. The mechanism of action has been hypothesized that the energy could result in analgesic effect and stimulation of angiogenesis and healing response and then relief of the symptoms. The effectiveness of radial shock wave on treatment of myofascial pain was reported by Jeon and colleagues in 2012.

The aim of this study is to compare the efficacy of acupuncture and radial shock wave therapy in patients with myofascial pain syndrome.

80 participants diagnosed with myofascial pain syndrome in trapezius muscle will be enrolled from the outpatient clinic of Department of Physical Medicine and Rehabilitation in Shin Kong Wu Ho-Su Memorial Hospital .

The patients will be randomized to either treatment groups: group 1, radial extracorporeal shock wave therapy (RSWT group) and group 2, acupuncture group (AC group).

All treatments will be given in the Department of Physical Medicine and Rehabilitation, and will be handled by a physiatrist who is familiar with both kinds of therapy.

The RSWT is delivered at 2 Hz with 2000 shock waves and the energy level of 0.056 mJ / mm2 in the trapezius muscle. Treatment point is the origin attachment of upper trapezius at the external occipital protuberance. RSWT will be performed once per week, and will be continued for 3 weeks.

Acupuncture is performed at Fenfchi (GB20) point over upper back. This acupoint is a common local point for treating upper back pain. Acupuncture therapy will be provided by the same physiatrist to all patients.

The primary outcome measures are VAS for pain and pain threshold. The secondary outcome measures are neck disability index, and patients' satisfaction. All subjects will be assessed by an independent, blinded investigator at baseline, post treatment and at 1-month after the treatments are completed.

Demographic data, including age, sex, employment status, and sleep quality, history of head or neck surgery, or other psychiatric and medical disorders will be recorded at baseline. A history will be taken concerning the duration of complaints (months), previous treatments (injections, physical therapy), and current pain medications. Concomitant diseases and the use of medications will be registered.

Eligibility Criteria:
Inclusion Criteria:Physical examination showed

* unilateral upper back pain,
* palpable intramuscular taut band,
* normal neurological examination
* presence of trigger points

Exclusion Criteria:

* bilateral neck pain
* pregnancy
* coagulopathy
* patients with pacemaker
* open wound at treatment area
* cervical spine fracture or previous operation around neck
* cervical myelopathy
* rheumatoid arthritis
* severe systemic disease