Anterior cervical plating reverses load transfer through multilevel strut-grafts

Denis Diangelo, Kevin Foley, Keith A. Vossel, Y. Raja Rampersaud, Thomas H. Jansen

Research output: Contribution to journalArticle

132 Citations (Scopus)

Abstract

Study Design. In vitro biomechanical study using a programmable testing apparatus that replicated physiologic flexion/extension cervical spine motion and loading mechanics. Objective. To determine the influence of anterior plating on multilevel cervical strut-graft mechanics in vitro. Summary of Background Data. The addition of anterior instrumentation does not prevent construct failure in multilevel cervical corpectomy. Methods. Six fresh human cadaveric cervical spines (C2-T1) were tested in the four following sequential conditions: harvested, C4-C6 corpectomy, strut-grafted, and strut- grafted with an anterior cervical plate. A force-sensing strut-graft was used to measure compression/tension, flexion/extension and lateral bending moments, and axial torsion. Parameters of stiffness, vertebral motion, and strut-graft loads were compared to determine differences between the four spine conditions. Results. Application of the anterior plate significantly increased the global stiffness (P < 0.01) and decreased the local motion (P ≤ 0.01) of the instrumented levels (C3-C7). Flexion of the strut-grafted spine loaded the strut-graft, whereas extension unloaded the strut-graft. With the anterior plate, flexion of the plated spine unloaded the strut- graft. Extension significantly loaded the strut-graft more than similar degrees of flexion in the strut-grafted condition (P = 0.01). Strut-graft loading end limits of 225 N were reached with a mean 7.5°extension in the plated spines. Conclusions. Anterior multilevel cervical plating effectively increases stiffness and decreases local cervical motion after corpectomy. However, anterior cervical plating also reverses graft loads and excessively loads the graft in extension, which may promote pistoning and failure of multilevel constructs.

Original languageEnglish (US)
Pages (from-to)783-795
Number of pages13
JournalSpine
Volume25
Issue number7
DOIs
StatePublished - Apr 1 2000

Fingerprint

Transplants
Spine
Mechanics

All Science Journal Classification (ASJC) codes

  • Orthopedics and Sports Medicine
  • Clinical Neurology

Cite this

Anterior cervical plating reverses load transfer through multilevel strut-grafts. / Diangelo, Denis; Foley, Kevin; Vossel, Keith A.; Rampersaud, Y. Raja; Jansen, Thomas H.

In: Spine, Vol. 25, No. 7, 01.04.2000, p. 783-795.

Research output: Contribution to journalArticle

Diangelo, Denis ; Foley, Kevin ; Vossel, Keith A. ; Rampersaud, Y. Raja ; Jansen, Thomas H. / Anterior cervical plating reverses load transfer through multilevel strut-grafts. In: Spine. 2000 ; Vol. 25, No. 7. pp. 783-795.
@article{28bc8199ddf149ef81c19eff9a314af8,
title = "Anterior cervical plating reverses load transfer through multilevel strut-grafts",
abstract = "Study Design. In vitro biomechanical study using a programmable testing apparatus that replicated physiologic flexion/extension cervical spine motion and loading mechanics. Objective. To determine the influence of anterior plating on multilevel cervical strut-graft mechanics in vitro. Summary of Background Data. The addition of anterior instrumentation does not prevent construct failure in multilevel cervical corpectomy. Methods. Six fresh human cadaveric cervical spines (C2-T1) were tested in the four following sequential conditions: harvested, C4-C6 corpectomy, strut-grafted, and strut- grafted with an anterior cervical plate. A force-sensing strut-graft was used to measure compression/tension, flexion/extension and lateral bending moments, and axial torsion. Parameters of stiffness, vertebral motion, and strut-graft loads were compared to determine differences between the four spine conditions. Results. Application of the anterior plate significantly increased the global stiffness (P < 0.01) and decreased the local motion (P ≤ 0.01) of the instrumented levels (C3-C7). Flexion of the strut-grafted spine loaded the strut-graft, whereas extension unloaded the strut-graft. With the anterior plate, flexion of the plated spine unloaded the strut- graft. Extension significantly loaded the strut-graft more than similar degrees of flexion in the strut-grafted condition (P = 0.01). Strut-graft loading end limits of 225 N were reached with a mean 7.5°extension in the plated spines. Conclusions. Anterior multilevel cervical plating effectively increases stiffness and decreases local cervical motion after corpectomy. However, anterior cervical plating also reverses graft loads and excessively loads the graft in extension, which may promote pistoning and failure of multilevel constructs.",
author = "Denis Diangelo and Kevin Foley and Vossel, {Keith A.} and Rampersaud, {Y. Raja} and Jansen, {Thomas H.}",
year = "2000",
month = "4",
day = "1",
doi = "10.1097/00007632-200004010-00005",
language = "English (US)",
volume = "25",
pages = "783--795",
journal = "Spine",
issn = "0362-2436",
publisher = "Lippincott Williams and Wilkins",
number = "7",

}

TY - JOUR

T1 - Anterior cervical plating reverses load transfer through multilevel strut-grafts

AU - Diangelo, Denis

AU - Foley, Kevin

AU - Vossel, Keith A.

AU - Rampersaud, Y. Raja

AU - Jansen, Thomas H.

PY - 2000/4/1

Y1 - 2000/4/1

N2 - Study Design. In vitro biomechanical study using a programmable testing apparatus that replicated physiologic flexion/extension cervical spine motion and loading mechanics. Objective. To determine the influence of anterior plating on multilevel cervical strut-graft mechanics in vitro. Summary of Background Data. The addition of anterior instrumentation does not prevent construct failure in multilevel cervical corpectomy. Methods. Six fresh human cadaveric cervical spines (C2-T1) were tested in the four following sequential conditions: harvested, C4-C6 corpectomy, strut-grafted, and strut- grafted with an anterior cervical plate. A force-sensing strut-graft was used to measure compression/tension, flexion/extension and lateral bending moments, and axial torsion. Parameters of stiffness, vertebral motion, and strut-graft loads were compared to determine differences between the four spine conditions. Results. Application of the anterior plate significantly increased the global stiffness (P < 0.01) and decreased the local motion (P ≤ 0.01) of the instrumented levels (C3-C7). Flexion of the strut-grafted spine loaded the strut-graft, whereas extension unloaded the strut-graft. With the anterior plate, flexion of the plated spine unloaded the strut- graft. Extension significantly loaded the strut-graft more than similar degrees of flexion in the strut-grafted condition (P = 0.01). Strut-graft loading end limits of 225 N were reached with a mean 7.5°extension in the plated spines. Conclusions. Anterior multilevel cervical plating effectively increases stiffness and decreases local cervical motion after corpectomy. However, anterior cervical plating also reverses graft loads and excessively loads the graft in extension, which may promote pistoning and failure of multilevel constructs.

AB - Study Design. In vitro biomechanical study using a programmable testing apparatus that replicated physiologic flexion/extension cervical spine motion and loading mechanics. Objective. To determine the influence of anterior plating on multilevel cervical strut-graft mechanics in vitro. Summary of Background Data. The addition of anterior instrumentation does not prevent construct failure in multilevel cervical corpectomy. Methods. Six fresh human cadaveric cervical spines (C2-T1) were tested in the four following sequential conditions: harvested, C4-C6 corpectomy, strut-grafted, and strut- grafted with an anterior cervical plate. A force-sensing strut-graft was used to measure compression/tension, flexion/extension and lateral bending moments, and axial torsion. Parameters of stiffness, vertebral motion, and strut-graft loads were compared to determine differences between the four spine conditions. Results. Application of the anterior plate significantly increased the global stiffness (P < 0.01) and decreased the local motion (P ≤ 0.01) of the instrumented levels (C3-C7). Flexion of the strut-grafted spine loaded the strut-graft, whereas extension unloaded the strut-graft. With the anterior plate, flexion of the plated spine unloaded the strut- graft. Extension significantly loaded the strut-graft more than similar degrees of flexion in the strut-grafted condition (P = 0.01). Strut-graft loading end limits of 225 N were reached with a mean 7.5°extension in the plated spines. Conclusions. Anterior multilevel cervical plating effectively increases stiffness and decreases local cervical motion after corpectomy. However, anterior cervical plating also reverses graft loads and excessively loads the graft in extension, which may promote pistoning and failure of multilevel constructs.

UR - http://www.scopus.com/inward/record.url?scp=0033998138&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0033998138&partnerID=8YFLogxK

U2 - 10.1097/00007632-200004010-00005

DO - 10.1097/00007632-200004010-00005

M3 - Article

VL - 25

SP - 783

EP - 795

JO - Spine

JF - Spine

SN - 0362-2436

IS - 7

ER -