Correction of posterior shoulder tightness is associated with symptom resolution in patients with internal impingement.

BACKGROUND: Glenohumeral internal rotation deficit (GIRD) and posterior shoulder tightness have been linked to internal impingement.
PURPOSE: To determine if improvements in GIRD and/or decreased posterior shoulder tightness are associated with a resolution of symptoms. STUDY
DESIGN: Cohort study; Level of evidence, 3.
METHODS: Passive internal rotation and external rotation (ER) range of motion (ROM) at 90 degrees of shoulder abduction and posterior shoulder tightness (cross-chest adduction in side lying) were assessed in 22 patients with internal impingement (11 men, 11 women; age 41 +/- 13 years). Treatment involved stretching and mobilization of the posterior shoulder. The Simple Shoulder Test (SST) was administered on initial evaluation and discharge. Changes in GIRD, ER ROM, and posterior shoulder tightness were compared between patients with complete resolution of symptoms versus patients with residual symptoms using independent t tests.
RESULTS: Patients had significant GIRD (35 degrees), loss of ER ROM (23 degrees), and posterior shoulder tightness (35 degrees) on initial evaluation (all P < .01). Physical therapy (7 +/- 2 weeks; range, 3-12 weeks) improved GIRD (26 degrees +/- 14 degrees; P < .01), ER ROM loss (14 degrees +/- 20 degrees), and posterior shoulder tightness (27 degrees +/-19 degrees). The SST improved from 5 +/- 3 to 11 +/- 1 (P < .01). A greater improvement in posterior shoulder tightness was seen in patients with complete resolution of symptoms (n = 12) compared with patients with residual symptoms (35 degrees vs 18 degrees; P < .05). Improvements in GIRD and ER ROM loss were not different between groups (GIRD, 25 degrees vs 28 degrees, P = .57; ER ROM, 14 degrees vs 15 degrees, P = .84).
CONCLUSION: Resolution of symptoms after physical therapy treatment for internal impingement was related to correction of posterior shoulder tightness but not correction of GIRD.