Accuracy of free hand technique of transpedicular screw fixation in correction of spinal deformities

Author(s): Dr. Kunal Dhurve and Dr. Vishal Patil

Abstract: Introduction: Pedicular screw fixation is now the novel technique to correct spinal deformities. Navigation or CT guided systems are not easily available in Indian scenario. Free hand technique of pedicle screw insertion is commonly practiced for degenerative spine and traumatic spine with fluoroscopic guidance, but for deformed spine fluoroscopy may not be always helpful. AIM: we intend to evaluate accuracy and safety free hand technique in kyphoscoliotic spine. Material and Methods: Twenty consecutive patients suffering from kyphoscoliosis underwent posterior stabilization using a total of 260 titanium/stainless steel transpedicular screws. The position of the screws inserted into the deformed spine was evaluated by postoperative computed axial tomography (CAT) scans. All patients underwent 3-mm thin-section postoperative CT. Pedicle perforations were classified as either medial or lateral breech and distance was measured of breach. Results: Of the 260 screws inserted into the deformed scoliotic spine 27 screws showed moderate lateral cortical perforation whereas 11 screws showed moderate medial cortical breech. These screws showed cortical perforation in the range of 2.1-4.0mm.One screw each showed cortical breech in the range of 4.1-6.0mm on medial and lateral side. Conclusion: This study concludes that with good knowledge of anatomy of spine, free hand thoracic pedicle screw insertion technique for the surgical treatment of normal and deformed thoracic spines without any radiographic guidance and/or intraoperative tracking devices appears to be a safe, and reliable procedure.

DOI: https://doi.org/10.22271/ortho.2017.v3.i3j.108