Atlantooccipital subluxation in a neonate with Down's syndrome. Case report and review of the literature.

Atlantooccipital subluxation (AOS) occurs in up to 63% of patients with Down's syndrome. However, presenting symptoms and the age at which preoperative screening becomes necessary have not been clearly delineated. Recently, a 16-day-old female with Down's syndrome and AOS presented to our institution. Following patent ductus arteriosus ligation, her neurological examination revealed trace movement, few spontaneous respirations, and left lower extremity clonus. Cervical spine radiographs revealed significant AOS. She was reduced and underwent a fusion from the occiput to C2. She gradually regained full strength and sensation. This case is the youngest example of AOS related to Down's syndrome described. It emphasizes the need for preoperative screening of all patients with Down's syndrome.