Search

The aim of this study is to present a rare case of chordoma in the odontoid process in which the tumor involved the odontoid process and compressed the spinal cord at the craniocervical junction. We report on the effectiveness and successful outcome of anterior microscopic tumor resection combined with posterior occipitocervical fixation and review the current standard treatment. A 39-year-old man presented with sudden dyspnea and quadriparesis caused by an unknown tumor compression at C2. Radiographic examination revealed a large destructive mass at C2 and heterogeneous enhancement. The patient received urgent surgical intervention by microscopic-assisted anterior tumor resection and posterior spinal fixation from the occiput to the C5 level. The pathohistologic reports for cytokeratins, epithelial membrane antigen, and S-100 protein were positive. The final diagnosis was chordoma of the odontoid process. At the 2-year follow-up, the patient's condition had improved, and a postoperative MRI showed no indication of tumor regrowth. Chordoma of the odontoid process or C2 body is very rare. The current standard management is wide tumor resection to prevent recurrence. The combined approach of anterior tumor resection with microscopic assistance and posterior stabilization of the occiput to C5 is the optimal treatment for this condition., (Copyright © 2022 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Orthopaedic Surgeons.)

Background: Understanding of the pedicle anatomy is necessary for pedicle screw placement; however, there have been few Thai studies reporting on thoracic pedicle morphometry., Objective: To determine important anatomical measurements for thoracic pedicle screw fixation., Material and Method: T1-T12 vertebral pedicles were evaluated in 27 cadavers. The diameter angle, length and entry point of the pedicle were measured., Results: The transverse diameter was smaller than the sagittal diameter at all levels. The narrowest transverse diameter was at the T5 level in males and T4 level in females. The pedicle diameter in males was statistically significantly greater than in females at all levels except at the T12 level. Most pedicles with a transverse diameter of 5.0 mm or less were found at the T4, T5, T6 and T7 levels. The transverse angle was widest at the T1 level; it faced medially at all levels. The sagittal angle was widest at the T12 level andfaced cephaladly at all levels. The axis length was shortest at the T1 level. Most entry points were at the inferolateral zone., Conclusion: A 4-mm diameter screw should be used carefully at the mid-thoracic levels for Thai people, especially females. Screw lengths of less than 30 mm are safe for placement at all levels. The safe zone for the pedicle entry point is in the inferolateral zone.