[Effect of muscular dysfunction on the development of shoulder joint in children with Erb's paralysis].

In order to evaluate the disturbances of development of the shoulder joint in children with Erb's paralysis the authors conducted an X-ray examination of the shoulder girdle and the shoulder in the anterior-posterior projection. The assessment of the functional state of the muscles of the shoulder girdle was made with the aid of clinical EMG. It was established that there was a retardation of growth and ossification of the radial head of the humerus on the affected side, a decrease in the longitudinal and cross-sectional sizes of the humerus, a retardation in the development of the joint scopular cavity, disorders in spacial interrelationship in the components of the shoulder joint and internal rotation of the shoulder joint. The structural and anatomical changes in the components of the shoulder joint are associated with disorders of the neurotrophic processes in the bone tissue and the muscular dysbalance.