RECONSTRUCTION OF THE HYPOPLASTIC POSTERIOR ARCH OF THE ATLAS WITH CALVARIAL BONE-GRAFTS FOR POSTERIOR ATLANTOAXIAL FUSION - TECHNICAL REPORT

POSTERIOR ATLANTOAXIAL FUSION is a common procedure performed for inst ability at C1-C2. This operation requires intact posterior elements of both the atlas and the axis. When this is not the case, the incorpora tion of the occiput and the lower spinal segments is usually required for adequate posterior fusion, but such a procedure limits the mobilit y of the upper cervical spine. A technique for the reconstruction of t he posterior arch of the atlas with calvarial bone is described in thi s report. This technique allowed the successful fusion of the C1 and C 2 vertebrae in a patient with traumatic atlantoaxial subluxation who a lso had a congenital absence of the posterior arch of the atlas.