Abstract

Surgical treatment interventions for low-back pain are increasing. Surgical risk associated with new techniques can be reduced by practice on synthetic spine replicas. However, current models for surgical training on intervertebral disk procedures do not represent average patients because they exhibit variable degrees of degeneration. A low-cost synthetic intervertebral disk device with lifelike sensory and visual feedback to enhance surgeon training was developed. Design criteria for the synthetic analog intervertebral disks (IVDs) were based on observations of fresh frozen human cadaveric disks, surgeon input, and literature descriptions; prototypes were designed to mimic a Grade I-II lumbar IVD. Qualitative evaluation was done by interviewing orthopedic surgeons during mock surgeries on the model. The surgical feel was quantitatively evaluated by a mock nucleotomy on prototypes and cadaveric specimens using instrumented surgical tools. In qualitative analysis, two orthopedic surgeons commented that the visual and tactile qualities of the model were similar to disks of adult spine surgery patients. Quantitative test results showed similarities between human and analog disks. The inexpensive synthetic IVD design successfully replicated the main features of a human cadaveric disk.

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