Is C1 Asymmetric Laminectomy Safer? A Cadaver Study

To investigate the difference in the length of C1 laminectomy between the right and left sides and to determine the importance of considering the dominant vertebral artery in reducing complication risks.

Five caucasian male cadavers were studied. The distance of the C1 posterior tubercle to the vertebral groove (A), the length of the vertebral groove (B), and the diameter of the vertebral artery were measured and statistically investigated. Computed tomography scans were also obtained from all cadaver specimens.

The mean distance of the C1 posterior tubercle to the vertebral groove (A) on the right side was 20.20 ± 2.16 mm and on the left side was 16.40 ± 2.88 mm. The mean distance of the vertebral groove (B) on the right side was 13.80 ± 0.83 mm and on the left side was 17.60 ± 0.89 mm. The mean diameter of the vertebral artery on the right side was 3.58 ± 0.83 mm and on the left side was 3.70 ± 0.10 mm.

The vertebral groove was longer on the dominant artery side. Therefore, the dominant and nondominant sides have different lengths of safe C1 laminectomy areas. The length of the laminectomy area to be performed on the dominant artery side is shorter than that on the nondominant side. In cases in which the C1 posterior arcus must be removed for decompression, asymmetric decompression should be performed to reduce the risk of vertebral artery injury.