The Journal of Bone and Joint Surgery, Vol 66, Issue 8 1178-1187, Copyright © 1984 by Journal of Bone and Joint Surgery, Inc
Postoperative neurological deficits in segmental spinal instrumentation. A study using spinal cord monitoring
RG Wilber, GH Thompson, JW Shaffer, RH Brown and CL Nash
We retrospectively analyzed the postoperative neurological complications in
137 patients who underwent a posterior spine fusion for scoliosis and had
concomitant somatosensory cortical evoked-potential spinal-cord monitoring.
The patients were divided into three specific operative groups: group 1,
forty-nine patients who had a Harrington rod with segmental wiring
(segmental spinal instrumentation); group 2, twenty patients who had Luque
segmental spinal instrumentation; and group 3, sixty-eight patients who had
a Harrington rod without segmental spinal instrumentation. There were
neurological complications in twelve (17 per cent) of the sixty-nine
patients in groups 1 and 2. Three patients (4 per cent) had a major injury
to the spinal cord and nine patients (13 per cent) had only transient
sensory changes. No difference was apparent between group 1 and group 2 in
the degree of operative correction of curves or in the incidence of
neurological complications. The one neurological complication (1.5 per
cent) that occurred in the sixty-eight patients in group 3 was a
Brown-Sequard syndrome. The factors related to increased risk for spinal
cord injury in groups 1 and 2 included: (1) the passage of sublaminar wires
in the thoracic and thoracolumbar spine, (2) intraoperative correction
exceeding the preoperative bending correction, and (3) the surgeon's lack
of adequate experience with the technique. With spinal cord monitoring we
were able to predict the impending major neurological deficits, but the
transient (sensory) changes that may be associated with segmental wiring
were less reliably predicted.