Craniovertebral junction malformations. Clinicoradiological findings, long-term results, and surgical indications in 63 cases.

The fate of a series of 63 patients operated on between 1953 and 1979 was studied retrospectively to assess the efficacy of neurosurgical treatment in relieving symptoms associated with craniovertebral junction (CVJ) malformations. Fifty-eight patients underwent posterior cervicomedullary decompression, and the other five underwent transoral clivus-atlanto-odontoidectomy. Long-term results with the posterior approach showed that 50% of the patients benefited from surgery, 25% remained unchanged, and 25% continued to deteriorate or died. Patients with dorsal nervous tissue and/or meningeal anomalies, such as Arnold-Chiari malformation, hydrosyringomyelia, dural fibrous ring, or obstruction of the cisterna magna, did better than patients with ventral cervicomedullary indentation caused by a clivus-atlanto-odontoid bone complex. Anterior decompression is preferable to a posterior approach only if the CVJ malformation involves a ventral deformity in the absence of dorsal compression by soft tissue.