During spine surgery, it is important to protect the nerves associated with the spinal column. These nerves carry messages to and from the brain, organs, and limbs, aiding them with proper movement and sensation.
The NVM5 Intraoperative Monitoring System provides real-time, precise, and reliable feedback to ensure nerve and spinal cord safety. By using this unique and advanced technology, the surgeon is provided with intraoperative information about the location and function of the nerves, assisting with safe implant placement and surgical technique during minimally disruptive spine procedures.
The NuVasive proprietary monitoring platform has been used to monitor over 160,000 spine surgeries. With the safety afforded by this nerve monitoring system, you can experience a faster recovery and a quicker return to your normal lifestyle.
What is EMG?
EMG stands for electromyography, which is the study of the electrical activity of muscles. It is a test used to determine the health and function of nerves and/or muscles.
Why is EMG Used in Surgery?
The spinal cord is the part of the central nervous system which extends from the brain stem to the lower spine through the bony protection of the spinal canal. It acts as a conduit for sensory and motor information to travel to and from the brain, respectively. The spinal cord usually ends at the second lumbar level (L2) and then extends as a bundle of individual nerves known as the cauda equina.
“Cauda equina” is Latin for “horse’s tail.” It is the lower extension of the spinal cord, comprised of individual nerve roots, which when bundled, resemble a horse’s tail. These nerve roots exit the spinal canal individually at each spinal level, giving rise to each level’s spinal nerves.
The shape of the vertebrae allow for the passage of the spinal cord from the brain to the lower part of the body through the spinal canal. From the spinal cord, spinal nerves exit the spinal canal between each vertebra on both sides. After exiting the spinal canal, these spinal nerves then further entwine and extend to send signals between your brain and your organs, muscles, and other tissues. The cervical spinal nerves innervate (provide muscle activity and sensation functions to) your upper back, arms, and hands. The lumbar spinal nerves innervate your lower back, abdomen, and legs. If any of these nerves are pinched by a bulging disc or the position of your vertebrae, for example, you might experience back, groin, and/or leg pain or numbness.
Myotomes are muscle groups that are innervated by particular spinal nerve levels. By knowing which spinal nerves innervate specific muscles, we can monitor those muscles for changes in the nerves’ health. For example, we can monitor the following muscle groups for information about the corresponding spinal nerves:
- Quadriceps (front thigh muscles) L2, L3, L4
- Anterior Tibialis (shin muscle)L4, L5
- Hamstrings (back thigh muscles) L5, S1
- Gastrocnemius (calf muscle) S1, S2