Occiput/C1-C2 fixations using intra-laminar screw of axis - A long-term follow-up

The surgical management of the craniocervical junction is challenging. Rigid posterior fixation of occiput/C1-C2 can be performed using a variety of surgical techniques including C2 pedicle/pars interarticularis, transarticular and intralaminar screw fixations.

Forty-one patients were treated with occipital plate/C1 lateral mass and C2 intra-laminar screw fixations for basilar invagination and congenital atlantoaxial subluxation, post-traumatic instability, tuberculous and rheumatoid arthritis-associated atlantoaxial dislocation. Out of forty-one, thirty-six patients had bilateral crossing intra-laminar screws and five had ipsilateral laminar screw fixation bilaterally.

Follow-up was done in thirty-nine patients from 6 months to 8 years (mean: 21 months) and solid osseous fusion could be achieved in all (100%). One patient was lost to follow-up and another patient died of a cause unrelated to surgical technique. Pre-operative and post-operative Neurosurgical Cervical Spine Scale showed improvement in all patients having features of myelopathy. There were no neurological or vascular complications. However, nine patients had posterior laminar breach, eight had anterior laminar penetrations and three had wound infections. One patient had transient bulbar palsy and one patient had hardware failure in the form of avulsion of the midline occipital plate.

Intra-laminar screw fixation is a safe alternative to transarticular and transpedicular/pars interarticularis fixation of C2 with advantage of having no risk of injury to vertebral artery and comparable biomechanical and pull-out strength.