Comparison of specific and non-specific treatment approaches for individuals with posterior capsule tightness and shoulder impingement symptoms: A randomized controlled trial

Abstract

Background: Posterior capsule tightness (PCT) is associated with shoulder pain and altered shoulder kinematics, range of motion (ROM), external rotation (ER) strength, and pain sensitization.

Objective: To assess the effects of two interventions on shoulder kinematics, Shoulder Pain and Disability Index (SPADI) scores, ROM, strength, and pressure pain threshold (PPT) in individuals with PCT and shoulder impingement symptoms.

Methods: In this prospectively registered randomized controlled trial 59 individuals were randomized to either an Experimental Intervention Group (EIG, n=31) or a Control Intervention Group (CIG, n=28). The low flexion (LF) test was used to determine the presence of PCT. Shoulder kinematics, SPADI scores, internal rotation (IR) and ER ROM, ER strength, and PPT were measured pre- and post-treatment. Those in the EIG received an intervention specific to pain and PCT and those in the CIG received a non-specific intervention, both 4 weeks in duration.

Results: Individuals in the EIG demonstrated more scapular upward rotation (P=.03; mean difference (MD)=3.3°; 95% Confidence Interval (CI)=1.3°, 4.9°) and improved value on the LF test (P=.02; MD=4.6°; 95%CI=0.7°, 8.6°) than those in the CIG after treatment. Both groups presented less anterior (P<.01; MD=-0.7mm; 95%CI=-1.3mm, -0.2mm) and superior (P<.01; MD=-0.5mm; 95%CI=-0.9mm, -0.2mm) humeral translations, decreased SPADI score (P<.01; MD=-23.6; 95%CI=-28.7, -18.4), increased IR ROM (P<.01; MD=4.6°; 95%CI=1.8°, 7.8°) and PPTs for upper trapezius (P<.01; MD=60.1kPa; 95%CI=29.3kPa, 90.9kPa), infraspinatus (P=.04; MD=47.3kPa; 95%CI=2.1kPa, 92.5kPa), supraspinatus (P<.01; MD=63.7kPa; 95%CI=29.6kPa, 97.9kPa), and deltoid (P<.01; MD=40.9kPa; 95%CI=12.3kPa, 69.4kPa) after treatment.

Conclusion: The experimental intervention was more effective at improving PCT as measured through changes in the LF test. No benefit of the specific approach over the non-specific intervention was noted for the remaining variables.

Keywords: Glenohumeral joint; Mobilization; Physical therapy; Rehabilitation; Scapula.

Conflict of interest statement

Conflicts of interest No conflicts of interest to disclosure

Copyright © 2021 Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia. All rights reserved.

Figures

Fig. 1

Flow diagram representing enrollment, allocation, procedures, and analysis for both groups. Abbreviations: SPADI, Shoulder Pain and Disability Index; IR, internal rotation; ER, external rotation, ROM, range of motion; PPT, pressure pain threshold.

Fig. 2

Protocols for the groups: Experimental group: A, B, and C) Progression of posterior capsule mobilization (arrows indicate the mobilization directions), D) Strengthening of the external rotators, E) Posterior capsule stretching; Comparison group: F) Sham ultrasound, G) Scapular squeezing exercise, H) Stretching of the upper trapezius.

Fig. 3

Pre and Postintervention scapular internal rotation (A), upward rotation (B), and tilt (C); and humeral anterior translation (D) and superior translation (E) during elevation of the arm in the sagittal plane for both groups. Values are mean (standard error). Abbreviations: EIG, experimental intervention group; CIG, comparison intervention group.