This 7-year-old boy with Hajdu-Cheney syndrome presented with cervical syringomyelia related to rapidly progressing platybasia. Decompressive craniectomy provided temporary improvement, and his clinical status was eventually stabilized after external immobilization, according to findings at 2.5 years of follow up. In a review of the literature the authors found 57 cases of the syndrome, only three of which were associated with syringomyelia. The youth of the patient, the severe form and rapid course of the disease, and the very specific anatomical conditions related to cranial and facial deformities raised various therapeutic problems.