Abstract
To assess the outcome and safety of transarticular C1–C2 screw fixation. The clinical and radiological outcomes of 15 patients treated with posterior atlanto-axial transarticular screw fixation and posterior wiring was assessed at a minimum follow up of 6 months. Indications for fusion were rheumatoid arthritis in 8 (instability in 6 and secondary degenerative changes in 2), non-union odontoid fracture 4, symptomatic os-odontoideum one, C1–C2 arthrosis one and irreducible odontoid fracture one. Fusion was assessed with plain x-rays including flexion extension films.
Twenty nine screws were placed under fluoroscopic guidance. Bilateral screws were placed in 14 patients and a single screw in one patient. This patient had a single screw placed due to the erosion of the contralateral C2 pars by an anomalous vertebral artery. All patients had radiological union. Two screws (7%) were malpositioned; neither was associated with clinical sequelae. No neurological or vascular injuries were noted.
Transarticular C1–C2 fusion yielded a 100% fusion rate. The risk of neurological or vascular injury can be minimised by thorough assessment of pre operative CT scans to assess position of the vertebral artery and use of intra operative lateral and AP fluoroscopy.
Correspondence should be addressed to the editorial secretary: Associate Professor Jean-Claude Theis, Department of Orthopaedic Surgery, Dunedin Hospital, Private Bag 1921, Dunedin, New Zealand.
