Thoracolumbar Surgical-tEMG
December 08, 2021
Walking is something many of us take for granted. Many of us do without a second thought, and walking gives us a level of freedom and accessibility that many other people don’t have. However, as patients get older, their mobility can be challenged by the obstacles of aging. When combined with all of the other hurdles patients face throughout their lives, the possibility of one medical victory can be enough to give them hope.
One 71-year-old female patient presented with a history of worsening lower back pain, difficulty walking, and right leg pain. She was admitted with bilateral lower extremity neurogenic claudication, severe adjacent level disease at L1-L2 with moderate bilateral recess stenosis, complete collapse, and severe degenerative changes. In addition to her immediate lower back condition, she also suffered from hypertension, diabetes, skin cancer, a head injury, hypothyroidism, and heart disease.
A prior malpositioned screw placement only exacerbated this patient’s symptoms. In these situations, a solution like intraoperative neuromonitoring is a chance at salvation for patients, especially those at a higher risk of postoperative complications. For this procedure, the patient’s surgical team partnered with Axis Neuromonitoring to provide the best chance at a successful outcome.
“Axis Neuromonitoring provides high quality intraoperative neurophysiological monitoring during spinal, brain, vascular, ENT and peripheral surgeries. We monitor the integrity of nerves and neurological responses along neural pathways to help surgeons identify and protect neural structures,” said Dr. Faisal R. Jahangiri, MD, CNIM, D.ABNM, FASNM, FASET of Axis Neuromonitoring in Richardson, TX.
To assist in this surgery, Axis neuromonitoring technicians used a multimodality approach including Somatosensory Evoked Potentials (SSEP), Electromyography (EMG), (Electroencephalogram (EEG), and Train of Four (TOF) to help secure the best possible result for the patient. The surgeon tested the misplaced screw during surgery and was informed by the Axis technician of a lower than sustainable nerve response from the left vatus lateralis muscle at 7mA. The surgeon then removed the screw and repositioned it to get a final value of 18mA, significantly improving the patient’s left thigh nerve response.
No neurological deficits were noted due to repositioning the malpositioned screw thanks to an excellent surgical staff and assistance from the Axis Neuromonitoring team. “Axis provides an onsite technologist and an offsite telemonitoring physician,” said Dr. Jahangiri. The addition of two neuromonitoring experts to the surgical team ensures that all possible resources are available so that patients can be better attended to during surgery and surgeons have more eyes on monitors while they operate.
Suppose the low screw threshold was not identified by intraoperative neuromonitoring. In that case, it may have resulted in a breached pedicle which could have caused damage to the spinal cord or the adjacent nerves. In other words, the patient could have experienced postoperative muscle weakness, numbness, severe pain, or foot drop.
