Spinal deformity surgery carries the risk of neurological injury. Neurophysiological monitoring allows early identification of intraoperative cord injury which enables early intervention resulting in a better prognosis. Although multimodal monitoring is the ideal, resource constraints make surgeon-directed intraoperative transcranial motor evoked potential (TcMEP) monitoring a useful compromise. Our experience using surgeon-directed TcMEP is presented in terms of viability, safety, and efficacy. We carried out a retrospective review of a single surgeon’s prospectively maintained database of cases in which TcMEP monitoring had been used between 2010 and 2017. The upper limbs were used as the control. A true alert was recorded when there was a 50% or more loss of amplitude from the lower limbs with maintained upper limb signals. Patients with true alerts were identified and their case history analyzed.Aims
Methods
We describe 13 patients with cerebral palsy and
lordoscoliosis/hyperlordosis of the lumbar spine who underwent a posterior
spinal fusion at a mean age of 14.5 years (10.8 to 17.4) to improve
sitting posture and relieve pain. The mean follow-up was 3.3 years
(2.2 to 6.2). The mean pre-operative lumbar lordosis was 108° (80
to 150°) and was corrected to 62° (43° to
85°); the mean thoracic kyphosis from 17° (-23° to
35°) to 47° (25° to 65°);
the mean scoliosis from 82° (0° to 125°)
to 22° (0° to 40°); the mean pelvic
obliquity from 21° (0° to 38°)
to 3° (0° to 15°); the mean sacral
slope from 79° (54° to 90°) to
50° (31° to 66°). The mean pre-operative
coronal imbalance was 5 cm (0 cm to 8.9 cm) and was corrected to
0.6 cm (0 to 3.2). The mean sagittal imbalance of -8 cm (-16 cm
to 7.8 cm) was corrected to -1.6 cm
(-4 cm to 2.5 cm). The mean operating time was 250 minutes (180
to 360 minutes) and intra-operative blood loss 0.8 of estimated
blood volume (0.3 to 2 estimated blood volume). The mean intensive
care and hospital stay were 3.5 days (2 to 8) and 14.5 days (10
to 27), respectively. Three patients lost a significant amount of
blood intra-operatively and subsequently developed chest or urinary
infections and superior mesenteric artery syndrome. An increased pre-operative lumbar lordosis and sacral slope were
associated with increased peri-operative morbidity: scoliosis and
pelvic obliquity were not. A reduced lumbar lordosis and increased
thoracic kyphosis correlated with better global sagittal balance
at follow-up. All patients and their parents reported excellent
surgical outcomes. Lordoscoliosis and hyperlordosis are associated with significant
morbidity in quadriplegic patients. They are rare deformities and
their treatment is challenging. Sagittal imbalance is the major
component: it can be corrected by posterior fusion of the spine
with excellent functional results. Cite this article:
