Thoracic Manual Therapy Improves Pain and Disability in Individuals With Shoulder Impingement Syndrome Compared With Placebo: A Randomized Controlled Trial With 1-Year Follow-up

Abstract

Objective: To investigate whether muscle energy technique (MET) to the thoracic spine decreases the pain and disability associated with shoulder impingement syndrome (SIS).

Design: Single-center, 3-arm, randomized controlled trial, single-blind, placebo control with concealed allocation and a 12-month follow-up.

Setting: Private osteopathic practice.

Participants: Three groups of 25 participants (N=75) 40 years or older with SIS received allocated intervention once a week for 15 minutes, 4 consecutive weeks.

Interventions: Participants were randomly allocated to MET to the thoracic spine (MET-only), MET plus soft tissue massage (MET+STM), or placebo.

Main outcome measures: Primary outcome measure: Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire.

Secondary outcome measures: Shoulder Pain and Disability Index (SPADI) questionnaire; visual analog scale (VAS) (mm/100): current, 7-day average, and 4-week average; Patient-Specific Functional Scale (PSFS); and Global Rating of Change (GROC). Measures recorded at baseline, discharge, 4-week follow-up, 6 months, and 12 months. Also baseline and discharge thoracic posture and range of motion (ROM) measured using an inclinometer. Statistical analysis included mixed-effects linear regression model for DASH, SPADI, VAS, PSFS, GROC, and thoracic posture and ROM.

Results: MET-only group demonstrated significantly greater improvement in pain and disability (DASH, SPADI, VAS 7-day average) than placebo at discharge (mean difference, DASH=-8.4; 95% CI, -14.0 to -2.8; SPADI=-14.7; 95% CI, -23.0 to -6.3; VAS=-15.5; 95% CI, -24.5 to -6.5), 6 months (-11.1; 95% CI, -18.6 to -3.7; -14.9; 95% CI, -26.3 to -3.5; -14.1; 95% CI, -26.0 to -2.2), and 12 months (-13.4; 95% CI, -23.9 to-2.9; -19.0; 95% CI, -32.4 to -5.7; -17.3; 95% CI, -30.9 to -3.8). MET+STM group also demonstrated greater improvement in disability but not pain compared with placebo at discharge (DASH=-8.2; 95% CI, -14.0 to -2.3; SPADI=-13.5; 95% CI, -22.3 to -4.8) and 6 months (-9.0; 95% CI, -16.9 to -1.2; -12.4; 95% CI, -24.3 to -0.5). For the PSFS, MET-only group improved compared with placebo at discharge (1.3; 95% CI, 0.1-2.5) and 12 months (1.8; 95% CI, 0.5-3.2); MET+STM at 12 months (1.7; 95% CI, 0.3-3.0). GROC: MET-only group improved compared with placebo at discharge (1.5; 95% CI, 0.9-2.2) and 4 weeks (1.0; 95% CI, 0.1-1.9); MET+STM at discharge (1.2; 95% CI, 0.5-1.9) and 6 months (1.2; 95% CI, 0.1-1.3). There were no differences between MET-only group and MET+STM, and no between-group differences in thoracic posture or ROM.

Conclusions: MET of the thoracic spine with or without STM improved the pain and disability in individuals 40 years or older with SIS and may be recommended as a treatment approach for SIS.

Keywords: Pain; Rehabilitation; Shoulder; Shoulder impingement syndrome.