Mobilization with movement plus exercise versus exercise alone for patients with central sensitization associated with chronic subacromial pain syndrome: a sham-controlled randomized clinical trial.

backgroundThe efficacy of mobilization with movement (MWM) in addressing central sensitization and widespread mechanical hyperalgesia in patients with subacromial pain syndrome (SPS) remains unclear. This study aimed to evaluate the efficacy of MWM combined with exercise in improving the Central Sensitization Inventory (CSI) score, widespread mechanical hyperalgesia, and functional disability in patients with central sensitization associated with SPS.

methodsThis study was designed as a single-blind, randomized, sham-controlled trial. Sixty-three adult patients with central sensitization associated with chronic SPS were randomly assigned to three groups (MWM, Sham MWM, and Control) using a permuted block randomization method. Outcomes were assessed at baseline, post-intervention (after three weeks), and at a three-month follow-up. The outcome measures included the CSI, pressure pain threshold measurements (PPT), and the Quick Disabilities of the Arm, Shoulder, and Hand questionnaire (Q-DASH). The CSI was used to assess emotional and somatic symptoms associated with central sensitization; PPTs evaluated local and widespread pain hypersensitivity; and the Q-DASH assessed upper extremity physical function and symptoms. A two-factor repeated-measures analysis of variance (group × time) with Bonferroni post-hoc correction was performed to analyze the main outcome variables.

resultsAt baseline, there were no significant differences in age, gender, or clinical characteristics among the groups. At the post-intervention stage, MWM combined with exercise did not result in superior improvements in CSI scores, local-widespread PPTs, or functional disability compared to sham-MWM or exercise alone (p > 0.05 for all). However, at the three-month follow-up, the MWM group showed significantly greater improvements in PPTs at the deltoid [p = 0.042, mean difference (MD) (95% CI): 0.6 (0.0 to 1.2)], brachioradialis [p = 0.028, MD (95% CI): 0.9 (0.1 to 1.7)], rectus femoris [p = 0.008, MD (95% CI): 0.9 (0.2 to 1.8)], and tibialis anterior [p = 0.029, MD (95% CI): 0.7 (0.1 to 1.4)] compared to the sham-MWM group. Additionally, significant differences were also found between the MWM and control groups in PPTs at the deltoid [p < 0.001, MD (95% CI): 1.0 (0.4 to 1.5)], brachioradialis [p = 0.012, MD (95% CI): 1.0 (0.2 to 1.8)], rectus femoris [p = 0.005, MD (95% CI): 0.9 (0.3 to 1.6)], and tibialis anterior [p = 0.022, MD (95% CI): 0.8 (0.1 to 1.5)].

conclusionsIn patients with central sensitization associated with chronic subacromial pain syndrome, the combination of mobilization with movement and exercise did not result in significant short-term (three-week) improvements in emotional and somatic symptoms of central sensitization or widespread pain hypersensitivity, compared to sham mobilization with movement plus exercise or exercise alone. However, this intervention led to greater mid-term (three-month) reductions in both local and widespread mechanical hyperalgesia in these patients.

trial registrationClinicalTrials.gov (Clinical trial number: NCT05524870, First Submitted Date: 15.02.2022).