Which type of instrumentation is most likely to cause trauma to the spinal cord?

The choice of sublaminar wires as the type of instrumentation most likely to cause trauma to the spinal cord is based on their design and application in surgical procedures. Sublaminar wires are often used to provide stabilization to the spine during spinal surgeries, but their placement involves threading them under the lamina of the vertebra. If not carefully positioned, these wires can exert pressure on the spinal cord or the nerve roots, potentially leading to injury.

The risk occurs because the wires can create localized tightness or impingement on the spinal structures, particularly in delicate areas where the spinal cord is closely situated to the bony anatomy. Additionally, if the wires are placed too high or inappropriately, they can introduce trauma during movement or even subsequent surgical manipulation.

In contrast, other options listed present different risk profiles. The strain gauge is generally used for measuring tensile forces and is less likely to directly impact neural structures. The Wyatt bolt, designed for stabilization, has a broader contact area which reduces the risk of localized trauma compared to wires. Subluminar needle electrodes are also designed for specific placements and typically have a reduced risk of causing trauma compared to sublaminar wires, as they are used for monitoring rather than structural support.