A modified microsurgical endoscopic assisted transpedicular corpectomy of the thoracic spine based on virtual 3D planning, technical note

Abstract Background The main difficulties of transpedicular corpectomies is lack of space for vertebral body replacement in the neighborhood of critical structures, the necessity for sacrifice of nerve roots in the thoracic spine and the extent of hemorrhage due to venous epidural bleeding. Objective We present a modified technique of transpedicular corpectomy by using an endoscopic assisted microsurgical technique performed through a single posterior approach. A 3D preoperative reconstruction could be helpful in preoperative planning for this complex anatomical region. Methods Surface and volume 3D reconstruction were performed by Amira or the Dextroscope. The clinical experience of this study includes 7 cases, two with an unstable burst fracture and five with metastatic destructive vertebral body disease, all with significant retropulsion and obstruction of the spinal canal. We performed a comparison with a conventional cohort of transpedicular thoracic corpectomies. Results Qualitative parameters of the 3D virtual reality planning included degree of bone removal, distance from critical structures such as myelon and implant diameter. Parameters were met in each case, with demonstration of optimal positioning of the implant without neurologic complications. In all cases, the endoscope was a significant help in identifying the origins of active bleeding, residual tumor, extent of bone removal, facilitating cage insertion in a minimally invasive way and helping to avoid root sacrifice on both sides. Conclusion Microsurgical endoscopic assisted transpedicular corpectomy may prove valuable in enhancing the safety of corpectomy in destructive vertebral body disease. The 3D virtual anatomical model greatly facilitated the preoperative planning.