Study design: Case report.
Objective: We report a case in which intraoperative spinal kyphosis after laminectomy led to neurological deterioration during intramedullary spinal cord tumor surgery at the cervicothoracic junction (CTJ).
Summary of background data: CTJ is a transitional zone between the cervical and thoracic spine; this region can be easily affected by mechanical stress. Although postoperative spinal instability or kyphosis after laminectomy at CTJ has been reported, no reports of intraoperative neurological deterioration after laminectomy exist.
Methods: The patient was a 40-year-old female with an intramedullary spinal cord tumor at T2-T4, which was suspected to be an ependymoma. She had no neurological deficit before the surgery. Although tumor removal surgery using a posterior approach was planned, the waves observed on intraoperative neurophysiological monitoring in the bilateral lower extremity disappeared soon after laminectomy.
Results: The waveform reappeared when we manually corrected the kyphosis at CTJ by pushing the spine. However, when we stopped the manual correction, the waveform disappeared again. The cause of neurological deterioration was strongly suspected to be a spinal kyphosis secondary to laminectomy. We removed the tumor after posterior instrumentation, and her neurological status was restored in 3 months postoperatively.
Conclusion: A minimal change in spinal alignment secondary to laminectomy could be a cause of intraoperative neurological deterioration during surgery at CTJ. Spinal fixation using spinal instrumentation should be performed before laminectomy, particularly in patients with preoperative neurological damage or severe spinal cord compression at CTJ.
Level of evidence: 4.