Background: The purposes of this study were to determine the prevalence of and the association between shoulder contracture and osseous deformity in a cohort of children with an obstetrical brachial plexus injury and to identify the risk factors for these complications.
Methods: In a retrospective cohort study, all children with an obstetrical brachial plexus injury who had been born between January 1991 and January 1998 at one academic medical center and all those with the same diagnosis who had been born elsewhere during the same period and were referred to the medical center within six weeks after delivery were evaluated at fixed time-intervals by one examiner. The patients underwent a final orthopaedic, neurological, and radiographic examination at a mean age of 3.7 years (range, one to seven years). Shoulder contracture was defined as a decrease in the passive range of motion in one or more directions compared with the range on the unaffected side. Osseous deformity was defined as a nonspherical humeral head or an abnormal glenoid.
Results: The prevalence of a shoulder contracture of >10° was 56% (twenty-nine of fifty-two patients), and the prevalence of an osseous deformity was 33% (sixteen of forty-eight patients with complete radiographic follow-up). In the children in whom complete neurological recovery was delayed (i.e., recovery was more than three weeks after birth), the prevalence of shoulder contracture was 54% (thirteen of twenty-four patients) and the prevalence of osseous deformity was 26% (six of twenty-three patients). A strong association was noted between shoulder contracture and osseous deformity (p = 0.004). Directly after birth, the presence of a clavicular fracture was the only factor that was associated (p = 0.016) with the development of an osseous deformity (but not with a shoulder contracture). At a later stage, speed and extent of neurological recovery were related to shoulder contracture and osseous deformity. An asymmetric appearance was noticed in children who had a contracture, including those who had complete neurological recovery.
Conclusions: The prevalence of shoulder contracture and osseous deformity in children with obstetrical brachial plexus injury was high, even in those with complete neurological recovery. These complications were strongly associated with one another. No symptom that appeared immediately after birth was identified as a factor that would predict the development of future shoulder contracture. A clavicular fracture was found to be significantly associated with the development of an osseous deformity at a later stage.
Level of Evidence: Prognostic study, Level II-1 (retrospective study). See Instructions to Authors for a complete description of levels of evidence.