Richard G. Fessler

Intraoperative neuromonitoring is recommended as standard practice for corrective scoliosis surgery. Common methods include somatosensory-evoked potentials (SSEPs) and transcranial motor-evoked potentials (TcMEPs), which have been shown to have a high diagnostic accuracy in detecting new neurological deficits postoperatively. Sequential compression devices (SCDs) are a common method for thromboprophylaxis in spine surgery and are not known to have many device-related complications. To date, there have been no reports of lower extremity ischemia secondary to SCD deflation failure detected by multimodality neuromonitoring during minimally invasive posterior spine surgery. We, therefore, present a case report of an 18-year-old male with adolescent idiopathic scoliosis who underwent minimally invasive posterior spinal fusion with instrumentation. Intraoperative decrease in SSEPs and TcMEPs were noted in the left leg shortly after incision before any instrumentation or reduction occurred. Further examination revealed that the left leg was hypoperfused compared with the right leg and that the left SCD was not properly deflating. Bilateral SCDs were removed, and perfusion and neuromonitoring returned to baseline immediately. Bilateral SCDs and the machine were replaced, and neuromonitoring remained within normal limits for the rest of the surgery. The patient had no postoperative neurologic or vascular deficits. Early detection of lower extremity ischemia by neuromonitoring resulted in the prompt identification and addressing of SCD malfunction, sparing devastating neurological and vascular injury to the patient's leg. This case reinforces the importance of neuromonitoring within spine surgery.