Mechanical testing of instrumentation. A test of mechanics

Spinal instrumentation has a primarily mechanical function, but mechanical testing procedures are designed more by expediency than by their ability to evaluate whether instrumentation will produce a good clinical outcome. Differing testing protocols preclude direct comparisons between measurements made in different laboratories. However, standardization of testing may not resolve the fact that much of the information from laboratory testing cannot be used in surgical decision-making. Researchers and journals that publish their work should focus on determining the mechanical requirements of instrumentation, including in vivo loading, the biologic response to instrumentation in the presence of pathology, and how this information can assist surgeons in selecting instrumentation in individual cases.