An alternate method for placement of C-1 screws

Abstract

<jats:sec> <jats:title>Object</jats:title> <jats:p>Several techniques for the surgical stabilization of the atlas and the axis have been described. Placement of C-1 lateral mass screws is one of the latest technical advances, and has gained popularity due to its efficacy and biomechanical advantages. However, the technique for placement of C-1 lateral mass screws, as first described by Harms, can cause excessive bleeding or irritation of the C-2 nerve. An alternative technique is available for the placement of C-1 lateral mass screws that completely avoids the C-2 nerve/ganglion and its associated venous plexus. This new technique mitigates some of the risk associated with the Harms techniques and eliminates the need to use specialized screws (that is, smooth shanks).</jats:p></jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>Twenty-six patients underwent atlantoaxial or occipitocervical fusions incorporating the alternative technique of C-1 screw placement. Three surgeons at 3 different institutions performed the surgeries. Standard lateral fluoroscopy and fully threaded polyaxial screws were used in each case.</jats:p></jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>Forty-nine screws were placed in C-1 lateral masses by using the new technique. Solid arthrodesis was achieved in all cases, with a mean follow-up period of 30 months. There were no cases of CSF leakage, new neurological deficit, injury to the C-2 ganglion, vertebral artery injury, or hardware failures.</jats:p></jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>The technique is a safe and effective way to fixate C-1 while avoiding the C-2 nerve/ganglion and venous plexus. The results indicate that excellent clinical and radiographic outcomes can be achieved with this new technique.</jats:p></jats:sec>

Placement of C1 Pedicle Screws Using Minimal Exposure: Radiographic, Clinical, and Literature Validation

“…11 Thomas et al describe a series of 26 patients who had C1 pedicle screws with good clinical outcomes. 4,11 No vertebral artery injuries were reported in any of these series utilizing pedicle or notched technique. 12 Obstacles of C1 pedicle screws are similar to that of lateral mass screws: vertebral artery injury, persistent 1st intersegmental artery injury, hypoglossal nerve injury, internal carotid artery injury, and occipital neuralgia.…”

“…Other failures were due to tumor involvement and non-healing unilateral fracture. 4 Focus remains on pre-operative imaging.…”

“…Adding complexity, variation of the vertebral artery course is seen in approximately 20% of patients. 4 The C1 pedicle screw technique involves the placement of C1 fixation without extensive dissection of the C1-C2 joint capsule. At its inception, this technique was performed with stereotactic guidance but advances have proven this method safe with fluoroscopy.…”

“…At its inception, this technique was performed with stereotactic guidance but advances have proven this method safe with fluoroscopy. 4,5 Our technique requires minimum dissection of the C1 arch in the placement of notched C1 pedicle screws. Typical technique for C1 pedicle screw placement focuses on intraoperative estimation of the C1 pedicle entry point as 2cm lateral from midline and 2mm from the inferior border of the posterior arch.…”

Late Complication of Surgically Treated Atlantoaxial Instability: Occipital Bone Erosion Induced by Protruded Fixed Titanium Rod: A Case Report

“…6 Indeed, almost 20% of patients will not be candidates for placement of transarticular screws due to the aberrant course of the vertebral artery. 7 Occipitocervical fixation is also an accepted treatment option for upper cervical spine instability. However, occipitocervical fixation affects flexion-extension function and may cause dysphagia by developing oropharyngeal stenosis.…”