An improved biomechanical testing protocol for evaluating spinal arthroplasty and motion preservation devices in a multilevel human cadaveric cervical model.
OBJECTIVE
An experimental study was performed to determine the biomechanical end-mounting configurations that replicate in vivo physiological motion of the cervical spine in a multiple-level human cadaveric model. The vertebral motion response for the modified testing protocol was compared to in vivo motion data and traditional pure-moment testing methods.


METHODS
Biomechanical tests were performed on fresh human cadaveric cervical spines (C2-T1) mounted in a programmable testing apparatus. Three different end-mounting conditions were studied: pinned-pinned, pinned-fixed, and translational/pinned-fixed. The motion response of the individual segmental vertebral rotations was statistically compared using one-way analysis of variance and Student-Newman-Keuls tests (p < 0.05 unless otherwise stated) to determine differences in the motion responses for different testing methods.


CONCLUSIONS
A translational/pinned-fixed mounting configuration induced a bending-moment distribution across the cervical spine, resulting in a motion response that closely matched the in vivo case. In contrast, application of pure-moment loading did not reproduce the physiological response and is less suitable for studying disc arthroplasty and nonfusion devices.
DiAngelo
Denis J
DJ
Department of Biomedical Engineering, The University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA.
Foley
Kevin T
KT
D000368:Aged; D000369:Aged, 80 and over; D001178:Arthroplasty / Q000295:instrumentation* / Q000379:methods / Q000592:standards; D001696:Biomechanical Phenomena / Q000295:instrumentation* / Q000379:methods / Q000592:standards; D002102:Cadaver; D002574:Cervical Vertebrae / Q000473:pathology / Q000601:surgery; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D013904:Thoracic Vertebrae / Q000473:pathology / Q000601:surgery