The advantage of the anterior transarticular screw is that it requires less muscle dissection than a posterior trans articular screw.
Check of feasibility
As with all screws that are placed at the C1 and C2 levels, a preoperative CT scan must be obtained to determine the feasibility of this screw.
Reduction may be performed by gentle traction, especially in acute cases. If not achieved or in more delayed cases, surgical reduction is indicated.
This involves soft tissue release (ligaments, capsules and scar tissues found in delayed presentation) followed by gentle manipulation.
The final reduction must be confirmed using a C-arm.
3. Trans articular screw insertion
Approach for screw insertion
A standard Smith Robinson approach to the cervical spine is utilized with the patient placed supine. The skin incision is made just below the mandible.
Careful blunt dissection is performed under magnification. The digastric muscle is encountered, as may the hypoglossal and superior laryngeal nerves.These are retracted rostrally to expose the C1-2 joint.
Screw entry point
The starting hole for the screw is 7-8 mm distal to the C1-C2 joint. It is 3-5 mm lateral to the medial boarder of the C1-C2 joint.
It is directed approximately 30° laterally and 30° posteriorly across the joint.
Drill, tap, measure and insert the screw under fluoroscopic guidance. The screw should not perforate the dorsal cortex of C1, nor should it violate the occipital cervical joint.
4. Anterior fusion of the C1-C2 joint
The joint is decorticated and packed with cancellous bone graft.
Patients are made to sit up in the bed on the evening following the operation.
A collar is commonly used following surgical stabilization to moderate patient activity.
The purpose of a collar is to prevent ranges of motion outside of limits deemed unfavorable for fracture healing. Collar is optional.
Patients with intact neurological status are made to stand and walk on the first day after surgery. Patients can be discharged when medically stable or sent to a rehabilitation center if further care is necessary. This depends on the comfort levels and presence of other associated injuries.
Patients are generally followed with periodical x-rays at 6 weeks, 3 months, 6 months, and 1 year.