Myofascial pain syndrome, or MPS, is a prevalent musculoskeletal disorder, which is characterised by the presence of muscle pain and tenderness. The inflammation and microtrauma that are the consequence result in adhesions between the fascial layers. It has been reported that these adhesions prevent the fasciae from sliding over each other and contribute to pain.

The rhomboid and trapezius muscles are commonly involved in MPS, which often affects the upper extremity.

This study hypothesized that muscle sliding decreases in patients with MPS. To this end, the investigators measured the amount of fascial sliding of the trapezius muscle in healthy volunteers and patients with MPS using M-mode ultrasound and a software-assisted program to investigate the differences and diagnostic value.

Inclusion Criteria:

• At least one active trigger point
• Moderate back pain lasting more than 3 months
• Diagnosis of MPS according to Travell and Simons diagnostic criteria
• Healthy volunteers

Exclusion Criteria:

• cervical disc disease
• Fibromyalgia
• Central or peripheral nerve disease
• Shoulder joint disease
• Malignancy
• Rheumatic disease
• those who had been treated for MPS within 6 months