Dry needling for myofascial pain: prognostic factors.

OBJECTIVES The study objectives were to evaluate outcomes in patients who have received dry needling treatments and to identify predictors of pain and disability. DESIGN The study was a prospective cohort follow-up design. SETTING The study was conducted at the Pain Clinic at Pingtung Christian Hospital, Taiwan. SUBJECTS Ninety-two (92) patients sick-listed for 3 months or longer for myofascial pain syndrome. INTERVENTIONS From February to October 2008, participants were treated at the pain clinic with dry needling of trigger points and muscle stretches of the involved muscles. OUTCOME MEASURES Data were collected by self-administered questionnaires to assess changes in pain intensity and pain interference. Data collection was performed at baseline and after 2, 4, and 8 weeks. Sociodemographic variables, symptom characteristics, and baseline outcome measures were analyzed using generalized estimating equation methodology. RESULTS The proposed dry-needling protocol reduced pain intensity and pain interference. Long duration of pain symptoms, high pain intensity, poor quality of sleep, and repetitive stress were associated with poor outcomes. CONCLUSIONS Dry needling is an effective treatment for reducing pain and pain interference. However, long pain duration, high pain intensity, poor quality of sleep, and repetitive stress are associated with poor outcomes. Treatment outcome depends not only on the dry needling protocol, but also on disease characteristics and patient demographic profile.