Which of the following is NOT a type of spinal instrumentation?

The Smith-Robinson technique is primarily associated with anterior cervical discectomy and fusion (ACDF) procedures, which involve accessing the cervical spine through the front of the neck. It is not classified as a type of spinal instrumentation as the other options are.

In contrast, Isola, Cotrel-Dubousset, and Luque L-rods refer to various systems and devices specifically designed for spinal instrumentation. The Isola system is known for its contributions to spinal stabilization, the Cotrel-Dubousset system has long been utilized for scoliosis correction and spinal stabilization, and the Luque L-rod is a type of implant used for spinal fusion that supports the spine during healing. Each of these systems serves a particular purpose in the surgical management of spinal pathologies.

In summary, the Smith-Robinson approach focuses on surgical techniques rather than the instrumentation of the spine itself, which clearly differentiates it from the other listed options that are specifically designed for spinal support and stabilization during and after surgical interventions.