Factors related to surgical outcome after posterior decompression and fusion for craniocervical junction lesions associated with osteogenesis imperfecta.

Treatment for craniocervical junction lesions associated with osteogenesis imperfecta (OI) has been described, but there are divergent views on operative procedures and preoperative and postoperative therapies due to the small number of cases. It has been suggested that a major procedure such as combined anterior and posterior surgery with concomitant ventriculoperitoneal (VP) shunting is required for OI associated with basilar impression (BI). However, here we report a case with a good outcome after posterior decompression fusion only. The patient was a 29-year-old woman with OI (Sillence type-IA) who had neurological symptoms of vertigo, nausea, and shaking during walking. Diagnostic imaging revealed hydrocephalus, severe BI, and Chiari type-II malformation. Preoperative Halo traction led to improvement in symptoms, and posterior decompression fusion from the occipital bone to C6 was subsequently performed. Lateral mass screws and Nesplon cables as sublaminar wiring for reinforcement for fusion were used in the operation. The patient wore a Halo vest for 4 weeks postoperatively. She experienced no symptoms postoperatively. Bone fusion and improved hydrocephalus were clear on images at 3 years after surgery, and the postoperative course has been good. In craniocervical junction lesions associated with OI, instability with compression of the nerve and bone fragility in multiple sites can become problematic. Anterior odontoid resection and posterior fusion are required for OI with BI to give ideal decompression on images. However, the results of this case suggest that a good postoperative outcome can be achieved by performing not the combination of anterior odontoid resection and VP shunting, but only with posterior decompression fusion, especially for OI cases of Sillence type-I.