Neurological function after total en bloc spondylectomy for thoracic spinal tumors

Abstract

Object Total en bloc spondylectomy (TES) for thoracic spinal tumors may in theory produce neurological dysfunction as a result of ischemic or mechanical damage to the spinal cord. Potential insults include preoperative embolization at 3 levels, intraoperative ligation of segmental arteries, nerve root ligation, and circumferential dural dissection. The purpose of this study was to assess neurological function after thoracic TES. Methods The authors performed a retrospective review of 79 patients with thoracic-level spinal tumors that had been treated with TES between 1989 and 2006. Neurological function was retrospectively analyzed according to the Frankel grading system. Of the 79 cases, 26 involved primary tumors and 53 involved metastatic tumors. The number of excised vertebrae was 1 in 60 cases, 2 in 13, and ≥ 3 in 6. The Frankel grade before surgery was B in 1 case, C in 16, D in 29, and E in 33. Results At the follow-up, the Frankel grade was C in 2 cases, D in 24, and E in 53. Of 46 cases with neurological deficits before surgery, neurological improvement of at least 1 Frankel grade was achieved in 25 cases (54.3%). Although the Frankel grade did not change in 21 patients, improvement in neurological symptoms within the same Frankel grade did occur in these patients. There were no cases of neurological deterioration. Conclusions There was no neurological deterioration due to preoperative embolization, ligation of segmental arteries, or ligation of thoracic nerve roots. Each of the cases with preoperative neurological deficits showed improvement in neurological symptoms. Data in the current study clinically proved that TES is a safe operation with respect to spinal cord blood flow. In TES, the spinal cord is circumferentially decompressed and the spinal column is shortened. An increase in spinal cord blood flow due to spinal shortening in addition to decompression was considered to have brought about a resolution of neurological symptoms with TES.