[Current concepts in perinatal brachial plexus palsy. Part 2: late phase. Shoulder deformities].

The incidence of obstetric brachial palsy is high and their sequelaes are frequent. Physiotherapy, microsurgical nerve reconstruction and secondary corrections are used together to improve the shoulder function. The most common posture is shoulder in internal rotation and adduction, because of the antagonist weakness. The muscle forces imbalance over the osteoarticular system, will result in a progressive glenohumeral joint deformity which can be recognized with a magnetic resonance image. Tendon transfers of the internal rotators towards the external abductor/rotator muscles, has good results, but has to be combined with antero-inferior soft-tissue releases, if passive range of motion is limited.