Anatomic classification system for surgical management of paraspinal tumors

Hypothesis: An anatomic classification system for paraspinal tumors that identifies complexity of regional anatomy, morbidity in complete or partial resection of anatomic structures, and potential complications may assist surgeons in preoperative planning. Design: Application of a 6-level anatomic classification system for paraspinal tumors by retrospective medical record analysis. The classification system is defined by the following divisions of the vertebral column: I (C3-T3), II (T3-T10), III (T10-L2), IV (L1-L5, anterior to spine), V (L2-L5, lateral to spine), and VI (S1-S5). Patients: All patients seen by us who underwent paraspinal tumor resection between 1997 and 2002. Setting: Tertiary referral facility. Main Outcome Measures: Level-specific preoperative and surgical procedures and expected and unexpected vascular and neurologic morbidity caused by surgical intervention. Results: Twenty-six patients met the inclusion criteria, and each of the levels (I through VI) of the classification system was represented by at least 2 patients. Expected morbidity that occurred because of surgical intervention included laryngeal paralysis in 1 patient with a level I tumor, femoral nerve palsy in 1 patient with a level V tumor, and neurogenic bladder and rectal dysfunction in 2 patients with level VI tumors. No unexpected neurologic deficit developed in any patient. Unanticipated intestinal ischemia and infarction occurred in 1 patient, who died after undergoing level IV surgery. Follow-up period ranged from 3 months to more than 5 years. Conclusion: Application of this 6-level anatomic classification system based on paraspinal tumor location may allow surgeons to anticipate specific surgical problems and to evaluate risks of resection and potential complications on the basis of regional anatomy.