Faculty Collaboration Database

Biomechanical effect of anterior cervical spine fusion on adjacent segments. Biomed Mater Eng 1999;9(1):27-38

Date

08/07/1999

Pubmed ID

10436851

Scopus ID

2-s2.0-0033027459 (requires institutional sign-in at Scopus site)   149 Citations

Abstract

The biomechanical effects of superior (C4-C5) and inferior (C5-C6) level fusions with different graft materials on the adjacent unaltered components were quantified using an anatomically accurate and experimentally validated C4-C5-C6 finite element model. Smith-Robinson and Bailey-Badgley fusion procedures were analyzed with five different types of inter-body fusion materials with varying stiffnesses. Intact and surgically altered finite element models were subjected to physiologic compression, flexion, extension and lateral bending. The external axial and angular stiffness, and the internal unaltered intervertebral disc (C5-C6 for the superior and C4-C5 for inferior fusion) and C5 vertebral body stresses were determined. The superior level fusion resulted in the highest increase in external response in lateral bending for all implant materials in both surgical procedures. In contrast, the inferior level fusion produced a higher increase in the C4-C5 disc and C5 vertebral body stresses in compression than the superior level fusion in both surgical procedures. The increased internal stress responses reflecting the changes in the load-sharing following inferior level fusion may explain clinical observations such as enhanced degeneration subsequent to surgery. Because of the inclusion of three levels in the present multi-segment finite element model, it was possible to determine these responses in the unaltered adjacent components of the cervical spine.

Author List

Maiman DJ, Kumaresan S, Yoganandan N, Pintar FA

Authors

Frank A. Pintar PhD Professor in the Biomedical Engineering department at Medical College of Wisconsin
Narayan Yoganandan PhD Professor in the Neurosurgery department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Biocompatible Materials
Biomechanical Phenomena
Bone Transplantation
Cervical Vertebrae
Elasticity
Equipment Design
Finite Element Analysis
Humans
Intervertebral Disc
Longitudinal Ligaments
Orthopedic Fixation Devices
Pliability
Spinal Diseases
Spinal Fusion
Stress, Mechanical
Tantalum
Titanium
Weight-Bearing