García MMA, Tovar LJ, Martínez GJM

Language: Spanish
References: 15
Page: 121-126
PDF size: 272.54 Kb.

ABSTRACT

Introduction: Atlanto-axial instability can result from trauma, infection, atrosis, or malformations and often require surgical fixation. Due to the proximity of the spinal cord, the thinness of the C2 pedicles, and the anatomical variants of the vertebral arteries, stabilization of the atlanto-axial complex is considered a surgical challenge. Objective: Description of a safe surgical technique for the placement of transpedicular screws in C2 guided by fluoroscopy in antero-posterior projection. Material and methods: Case series of patients with spinal cord trauma and degenerative processes of the cervical spine, which required the placement of transpedicular screws in C2, at the General Hospital of Querétaro, ages over 16 years. The presurgical classification by computed tomography of Rex AW Marco and that of Sang-Hun Lee were used to calculate the pedicle diameter and classify the type of intra-axial vertebral artery and thus determine the risk of injury to nerve-vascular structures. The placement of the transpedicular screw to C2 was performed using the intraoperative fluoroscopy technique in anteroposterior projection. All patients underwent a postsurgical tomographic study and the Masashi Neo grade classification of the placement of the transpedicular screw in C2 was used. Results: A total of 15 cases; 2 women and 13 men with a diagnosis of 7 with spinal cord trauma and 8 with degenerative disease of the cervical spine, mean age 60 years. 28 pedicles of C2 were instrumented. Fourteen low-risk pedicles, 12 moderate-risk, and 2 high-risk pedicles were instrumented. The Masashi Neo grade classification in the post-surgical tomographic study to evaluate the position of the transpedicular screws in C2. Of 28 instrumented pedicles, the postsurgical tomographic position was (28) grade 0. Conclusion: With the use of fluoroscopy in anteroposterior projection, we can identify the trans-surgical trajectory of the transpedicular screw in C2, identifying the safe area for its placement.

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