Background
Muscle imbalance of the shoulder results in weak external rotation and abduction. Active internal rotation and adduction can cause glenohumeral joint deformity with late posterior dislocation.
Patients and methods
This prospective study conducted from 2004 to 2009 included 34 patients, 18 girls and 16 boys, with a mean age of 4 years (1–7 years). The right side was affected in 19 patients, whereas the left side was affected in 15 patients. All patients suffered from obstetric brachial plexus palsy with internal rotation contracture and defective shoulder abduction plus posterior dislocation or subluxation of the humeral head. These patients were treated by soft tissue release (subscapularis slide and anterior soft tissues release) with or without tendon transfer (latissimus dorsi and teres major to infraspinatus).
Conclusion
Subscapularis release provided an objective functional benefit; however, it degraded over time. Teres major and latissimus dorsi to infraspinatus transfer is a useful procedure for correction of defective shoulder abduction and external rotation in obstetric brachial plexus palsy as it increases the stabilizing action of the rotator cuff, thus allowing the deltoid to act with maximal force.