Biomechanical comparison of a two-level anterior discectomy and a one-level corpectomy, combined with fusion and anterior plate reconstruction in the cervical spine

Kamran Aghayev; James J Doulgeris; Sabrina A Gonzalez-Blohm; Mohammed Eleraky; William E Lee 3rd; Frank D Vrionis

doi:10.1016/j.clinbiomech.2013.10.016

Biomechanical comparison of a two-level anterior discectomy and a one-level corpectomy, combined with fusion and anterior plate reconstruction in the cervical spine

Clin Biomech (Bristol, Avon). 2014 Jan;29(1):21-5. doi: 10.1016/j.clinbiomech.2013.10.016. Epub 2013 Oct 30.

Authors

Kamran Aghayev¹, James J Doulgeris², Sabrina A Gonzalez-Blohm³, Mohammed Eleraky¹, William E Lee 3rd⁴, Frank D Vrionis¹

Affiliations

¹ H. Lee Moffitt Cancer Center & Research Institute, NeuroOncology Program, Tampa, FL 33612, USA; Department of Neurosurgery and Orthopedics, College of Medicine, University of South Florida, Tampa, FL 33612, USA.
² H. Lee Moffitt Cancer Center & Research Institute, NeuroOncology Program, Tampa, FL 33612, USA; Dept. of Mechanical Engineering, University of South Florida, Tampa, FL 33612, USA.
³ H. Lee Moffitt Cancer Center & Research Institute, NeuroOncology Program, Tampa, FL 33612, USA. Electronic address: sabrina.gonzalezblohm@moffitt.org.
⁴ Dept. of Chemical & Biomedical Engineering, University of South Florida, Tampa, FL 33612, USA.

PMID: 24239024
DOI: 10.1016/j.clinbiomech.2013.10.016

Abstract

Background: Common fusion techniques for cervical degenerative diseases include two-level anterior discectomy and fusion and one-level corpectomy and fusion. The aim of the study was to compare via in-vitro biomechanical testing the effects of a two-level anterior discectomy and fusion and a one-level corpectomy and fusion, with anterior plate reconstruction.

Methods: Seven fresh frozen human cadaveric spines (C3-T1) were dissected from posterior musculature, preserving the integrity of ligaments and intervertebral discs. Initial biomechanical testing consisted of no-axial preload and 2Nm in flexion-extension, lateral bending and axial rotation. Thereafter, discectomies were performed at C4-5 and C5-6 levels, then two interbody cages and an anterior C4-C5-C6 plate was implanted. The flexibility tests were repeated and followed by C5 corpectomy and C4-C6 plate reconstruction. Biomechanical testing was performed again and statistical comparisons among the means of range of motion and axial rotation energy loss were investigated.

Findings: The two-level cage-plate construct had significantly lower range of motion than the one-level corpectomy-plate construct (P≤0.03). Axial rotation energy loss was significantly (P≤0.03) greater for the corpectomy-plate construct than for the two-level cage-plate construct and the intact condition.

Interpretation: A two-level cage-plate construct provides greater stability in flexion, extension and lateral bending motions when compared to a one-level corpectomy-plate construct. A two-level cage-plate is more likely to maintain axial balance by reducing the energy lost in axial rotation.

Keywords: Anterior cervical corpectomy and fusion (ACCF); Anterior cervical discectomy and fusion (ACDF); Energy loss; Range of motion (RoM).

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Biomechanical Phenomena / physiology
Biophysics / instrumentation
Bone Plates*
Cadaver
Cervical Vertebrae / surgery*
Diskectomy / instrumentation
Diskectomy / methods*
Female
Humans
Internal Fixators
Intervertebral Disc
Male
Middle Aged
Range of Motion, Articular / physiology*
Rotation
Spinal Fusion / methods*