Objectives 

This study aimed to compare continuous and pulsed ultrasound therapy with sham ultrasound in terms of pain, severity of muscle spasm, function, depression, and quality of life in patients with myofascial pain syndrome.

Design 

Patients were randomly divided into three groups, including the continuous ultrasound group (3 MHz, 1 W/cm², n = 20), the pulsed ultrasound group (3 MHz, 1 W/cm², 1:1 ratio, n = 20), and control group (sham, n = 20). The primary outcome measures were severity of pain at rest and during activity (visual analog scale, 0–10 cm). The secondary outcome measures were function (Neck Pain and Disability Scale), depressive mood (Beck Depression Scale), and quality of life (Nottingham Health Profile). All evaluations were performed at baseline, after treatment, and at the 6th and 12th wks.

Results 

All three groups had significant improvements in all of the pain scores, the severity of muscle spasms, function assessments, and certain subparameters of the quality of life scale (P < 0.05). The continuous ultrasound group had significantly greater improvements in pain at rest (P < 0.05). However, no statistically significant differences were observed in the other parameters (P > 0.05).

Conclusions 

Continuous ultrasound therapy is more efficient in reducing pain at rest for myofascial pain syndrome patients than is sham or pulsed ultrasound therapy.