Free Hand Technique For Lateral Mass Screws Insertion; A Safe, Accurate, and Simple Procedure For Posterior Cervical Spine Fixation.

Abstract

Objective: To asses the feasibility safety and  accuracy of the free hand technique in insertion of Lateral mass screws in the sub-axial spine. Patients and methods: 30 patients with cervical canal stenosis and multiple disc prolapse were operated on in Benha university hospitals with 172 lateral mass screws inserted with freehand technique through a midline posterior approach. Post-operative computed tomography CT scans were used to assess the accuracy and safety of the free hand technique.  Results: One hundred seventy-two screws were inserted in 30 patients with an average of 6 screws per case. A post-operative CT scan was done to assess the position and trajectory of the screws as well. 172 screws inserted easily and correctly with no complications while 8 screws were failed to be inserted because of a violation of the lateral mass during the insertion. No vascular nor neurological complications were encountered in the postoperative period or the follow-up period. Conclusion: The freehand technique is a safe and reliable surgical technique to insert lateral mass screws with a very good post-operative purchase and a high level of safety and feasibility. Neurovascular complications are usually avoidable when using this trajectory.