Any spine surgery is a very delicate operation. Care must be taken to prevent damage to the spinal cord, spinal nerves, and blood vessels supplying these neural components. Damage to the blood vessels and loss of blood supply to the spinal cord can have serious consequences.
Surgeons do have an important tool available during spinal surgery to monitor patients called intraoperative neuromonitoring or IOM. IOM methods include the wake-up test, somatosensory-evoked potentials (SSEP), transcranial motor-evoked potentials (tcMEP), spinal cord MEPs, spontaneous electromyography (sEMG), and triggered electromyography (tEMG).
Each one of these tests has its own purposes and functions. But the basic idea behind this type of monitoring is to make sure moment-by-moment during the procedure that no injury has occurred. This is called real-time monitoring. Warning is given so that any damage can be prevented or reversed.
There isn’t one-individual test that works for all patients or that monitors all functions of the spinal cord. If the surgeon wants to monitor both sensory and motor function, then more than one test will certainly be needed. That’s referred to as multimodality intraoperative monitoring or MIOM. MIOM is a great help when the surgeon is trying to remove a spinal tumor completely but without damaging the neural tissues or creating paralysis or other disability.
For now, the use of intraoperative monitoring (IOM) is still optional, not required in all spinal surgeries. Because there’s not enough evidence to support specific protocols, there isn’t a legal requirement yet for use of these tests.
Patients must understand that even with the best of testing available, problems can develop — even permanent paralysis is still a possibility. Intraoperative monitoring (IOM) isn’t really needed for the more simple spinal procedures, so patients shouldn’t expect this to be a standard part of every spinal operation.
Your question is a good one and one that you can certainly pose to the surgeon. He or she may already be using one or more of these tests. The surgeon who understands IOM will know when and how to use it best. None of the tests can replace a clear understanding of neurologic and vascular anatomy. Likewise, final outcomes of complex spinal surgery still require a high level of technical skill on the part of the surgeon.