Thoracic Spine Manipulation in Individuals With Subacromial Impingement Syndrome Does Not Immediately Alter Thoracic Spine Kinematics, Thoracic Excursion, or Scapular Kinematics: A Randomized Controlled Trial.

Abstract

Randomized controlled trial. To determine if thoracic spinal manipulative therapy (SMT) alters thoracic kinematics, thoracic excursion, and scapular kinematics compared to a sham SMT in individuals with subacromial impingement syndrome, and also to compare changes in patient-reported outcomes between treatment groups. Prior studies indicate that thoracic SMT can improve pain and disability in individuals with subacromial impingment syndrome. However, the mechanisms underlying these benefits are not well understood. Participants with shoulder impingement symptoms (n = 52) were randomly assigned to receive a single session of thoracic SMT or sham SMT. Thoracic and scapular kinematics during active arm elevation and overall thoracic excursion were measured before and after the intervention. Patient-reported outcomes measured were pain (numeric pain-rating scale), function (Penn Shoulder Score), and global rating of change. Following the intervention, there were no significant differences in changes between groups for thoracic kinematics or excursion, scapular kinematics, and patient-reported outcomes (P>.05). Both groups showed an increase in scapular internal rotation during arm raising (mean, 0.9°; 95% confidence interval [CI]: 0.3°, 1.6°; P = .003) and lowering (0.8°; 95% CI: 0.0°, 1.5°; P = .041), as well as improved pain reported on the numeric pain-rating scale (1.2 points; 95% CI: 0.3, 1.8; P<.001) and function on the Penn Shoulder Score (9.1 points; 95% CI: 6.5, 11.7; P<.001). Thoracic spine extension and excursion did not change significantly following thoracic SMT. There were small but likely not clinically meaningful changes in scapular internal rotation in both groups. Patient-reported pain and function improved in both groups; however, there were no significant differences in the changes between the SMT and the sham SMT groups. Overall, patient-reported outcomes improved in both groups without meaningful changes to thoracic or scapular motion. Therapy, level 1b-.