A novel testing platforms for characterizing cervical spine biomechanics.

摘要

The biomechanics and medical communities deserve a better understanding of cervical spine properties to allow improvement of current treatment methods for spinal trauma and disease. It is inherently difficult to make experimental in-vivo measurements of cervical spine kinematics and current in-vitro methods and results with cadaveric specimens can have significant variations. Previous methods have included custom cable-pulley systems, material tensile testers, parallel robots, and other platforms intended to apply pure moment loading to specimens. I propose a new spine testing paradigm using a six degrees of freedom serial manipulator for characterizing biomechanical properties, including range of motion (ROM), neutral zone (NZ), and other general spinal properties. This tool will be able to test individual functional spinal units (FSU) as well as multi-body segments in a modular framework. With this method, the various changes in kinematics can be characterized under a wide range of testing conditions, e.g., different implants, disk degeneration, ligament detachment, and other conditions. Another advantage of this test design is the ability to re-create complex physiological motion; which is clinically beneficial for studying specific motions. Previous studies were limited to analyzing flexion-extension, lateral bending, and axial rotation to their extreme values. This new system can perform motions such as flexion with axial rotation under a compressive load, representing common neck motion. With the ability to create richer data, the fundamental understanding of the cervical spine will be improved. Furthermore, these data can be used to calibrate and validate finite element (FE) and multi-body dynamic models.