Paraplegia resulting from vessel ligation

Study Design. This is a retrospective review of clinical records for evidence of paraplegia specifically resulting from segmental vessel ligation during anterior spinal surgery. Objectives. To determine the precise risk rate, and to potentially identify risk factors. Summery of Background Data. Although many authors have alluded to this risk, the exact risk rate and risk factors have never been identified. Methods. All patients having an anterior approach involving T1-L3 were reviewed. The two reviewers were not involved in any of the surgeries. The 1197 cases were consecutive from 1967 to 1991. Results. There were no paralyses. Conclusions. There would appear to be virtually no risk to segmental vessel ligation provided: 1) vessel ligation is unilateral, 2) done on the convexity of a scoliosis, 3) ligated at midvertebral body level, and 4) hypotensive anesthesia is avoided. Soft clamping with somatosensory-evoked potential monitoring does not appear justified.