Effects of Low-Load Exercise on Postneedling-Induced Pain After Dry Needling of Active Trigger Point in Individuals With Subacromial Pain Syndrome

Abstract Background The application of dry needling usually is associated with postneedling-induced pain. A postneedling intervention reduce this adverse event is needed. Objective To determine the effectiveness of low-load exercise on reducing postneedling-induced pain after dry needling of active trigger points (TrPs) in the infraspinatus muscle in subacromial pain syndrome. Design A 72-hour follow-up, single-blind randomized controlled trial. Setting Urban hospitals. Participants Individuals with subacromial pain syndrome (n = 90, 52% female, mean age: 35 ± 13 years) with active TrPs in the infraspinatus muscle. Interventions All individuals received dry needling into the infraspinatus active TrP. Then, they were divided randomly into an experimental group, which received a single bout of low-load exercise of shoulder muscles; a placebo group, which received inactive ultrasound for 10 minutes; and a control group, which did not receive any intervention. Outcome Measures Numerical Pain Rating Scale (0-10 point) was administered postneedling, immediately postintervention (2 minutes), and 24, 48, and 72 hours after needling. Shoulder pain (Numerical Pain Rating Scale, 0-10) and disability (Disabilities of the Arm, Shoulder and Hand; Shoulder Pain and Disability Index) were assessed before and 72 hour after needling. Results The 5 × 3 analysis of covariance showed that the exercise group demonstrated a larger decrease in postneedling-induced pain immediately after ( P = .001), 24 hours ( P = .001), and 48 hours after ( P = .006) than placebo or control groups. No differences were found at 72 hours ( P = .03). Similar improvements in shoulder pain ( P < .001) and related disability (Disabilities of the Arm, Shoulder and Hand: P < .001; Shoulder Pain and Disability Index: P < .001) were observed 72 hours after needling, irrespective of the treatment group. Conclusions Low-load exercise was effective for reducing postneedling-induced pain on active TrPs in the infraspinatus muscle 24 and 48 hours after needling. The application of a postneedling intervention did not influence short-term pain and disability changes. Level of Evidence To be determined.