Atlantoaxial joint distraction as a treatment for basilar invagination: A report of an experience with 11 cases

Objective: A novel method of treatment of basilar invagination that involves distraction of the atlantoaxial joint using specially designed spiked spacers is described. Bone graft that is additionally placed within the appropriately prepared atlantoaxial joint and posterior to the arch of atlas and lamina of C2 provides bony fusion.
Materials and Methods: Between December 2002 and April 2007, 11 patients underwent the discussed method of fixation at the Department of Neurosurgery, King Edward Memorial Hospital in Mumbai, India. All 11 patients had "congenital" basilar invagination and the symptoms were progressive in nature.
Results: The mean follow-up period was 21 months (range 8-40 months). Neurological improvement and successful distraction with atlantoaxial stabilization and ultimate bone fusion was achieved in all the patients and was documented with dynamic radiography. There were no neurological, vascular, or infective complications.
Conclusions: We conclude that the described method of atlantoaxial joint distraction and fixation provides an alternative treatment strategy for cases with basilar invagination. "Joint distraction" as a stand-alone method could provide reduction of basilar invagination and firm stabilization in such cases.

Keywords
Atlantoaxial dislocation, atlantoaxial joint, atlas, axis, basilar invagination