This retrospective review evaluated the prevalence of shoulder contracture and glenohumeral joint osseous deformity in patients with obstetrical brachial plexus injuries at one institution in Amsterdam. These patients were identified over a seven-year period between January 1991 and January 1998. Shoulder contracture was defined as a decrease in passive range of motion of greater than 10 degrees compared to the contralateral side. Osseous deformity was defined as a non-spherical humeral head or an abnormal glenoid. The prevalence of shoulder contracture was found to be 56%, for a cutoff of asymmetric motion of 10 degrees or greater. When the criteria were increased to 20 degrees and 30 degrees, the prevalence of a shoulder contracture was 31% and 17%, respectively. The most frequently effected direction was horizontal adduction followed the by lateral rotation in adduction. The median age of these children at the time their shoulder contracture was first documented was 0.3 years (range, 0.1-2.7 years). The prevalence of osseous deformity was 33%. An abnormal glenoid fossa was seen in 80% and a non-spherical humeral head was seen in 32%. A significant association was found between the prevalence of contractures of greater than 10 degrees and osseous deformity. Both shoulder contracture and osseous deformity were found to be strongly associated with the speed and extent of neurological recovery. The presence of a clavicular fracture at birth was found to be associated with osseous deformity of the glenohumeral joint but not with a shoulder contracture.
This study confirms a high prevalence of shoulder contracture and osseous deformity in patients with obstetrical brachial plexus injuries. Unexpected however, is that contractures were generally first documented within the first six months of life. Even in patients with a complete neurological recovery, 26% exhibited osseous deformity. The main factors associated with both shoulder contracture and osseous deformity were speed and extent of neurological recovery. There were no identified factors at birth that were correlated with the development of a shoulder contracture or osseous deformity. The association of a clavicle fracture with the development of an osseous deformity is of uncertain consequence. This study confirms a high prevalence of shoulder deformity in patients with an obstetrical brachial plexus injury. It indicates that essentially all children with an obstetrical brachial plexus injury are at risk for the development of shoulder contracture or osseous abnormality and this should be evaluated fairly early to minimize progressive contracture and the potential development of permanent posterior glenohumeral joint dislocation.
J Bone and Joint Surg