Influence of endplate size and implant positioning of vertebral body replacements on biomechanics and outcome.
Compression
Endplate
Replacement
Spine
Subsidence
Journal
Clinical biomechanics (Bristol, Avon)
ISSN: 1879-1271
Titre abrégé: Clin Biomech (Bristol, Avon)
Pays: England
ID NLM: 8611877
Informations de publication
Date de publication:
01 2021
01 2021
Historique:
received:
27
05
2020
revised:
15
12
2020
accepted:
15
12
2020
pubmed:
30
12
2020
medline:
12
6
2021
entrez:
29
12
2020
Statut:
ppublish
Résumé
Spinal stabilization by an anterior vertebral body replacement is frequently used in patients suffering from destroyed vertebral bodies. The aim of this study was to analyse (i) the choice of endplate size and positioning of vertebral body replacements in daily patient care and (ii) if these factors have an influence on clinical and radiological outcomes. Patients' outcomes were analysed three years after vertebral body replacement implantation using the visual analogue scale spine score. Safe zones on the vertebral body endplates were defined. Overall endplate coverage and implant subsidence were evaluated by CT and X-ray. Compression tests were performed on 22 lumbar vertebral bodies to analyse endplates sizes' influence on subsidence. Mean coverage of the vertebral body's superior and inferior endplates by the vertebral body replacement was 27.8% and 30.8%, respectively. Mean overlap of the safe zone by the implant was 49.8% and 40.6%. Mean subsidence was 1.1 ± 1.2 mm, but it did not have any effect on the outcome. In the compression tests, no significant difference (p = 0.468) was found between the two endplate sizes. Coverage of vertebral body endplates and positioning of implants in the safe zone did not entirely comply with the given recommendations. The amount of endplate coverage had no influence on subsidence or long-term outcomes in daily patient care. On the other hand, correct positioning of the implant may influence its subsidence.
Sections du résumé
BACKGROUND
Spinal stabilization by an anterior vertebral body replacement is frequently used in patients suffering from destroyed vertebral bodies. The aim of this study was to analyse (i) the choice of endplate size and positioning of vertebral body replacements in daily patient care and (ii) if these factors have an influence on clinical and radiological outcomes.
METHOD
Patients' outcomes were analysed three years after vertebral body replacement implantation using the visual analogue scale spine score. Safe zones on the vertebral body endplates were defined. Overall endplate coverage and implant subsidence were evaluated by CT and X-ray. Compression tests were performed on 22 lumbar vertebral bodies to analyse endplates sizes' influence on subsidence.
FINDING
Mean coverage of the vertebral body's superior and inferior endplates by the vertebral body replacement was 27.8% and 30.8%, respectively. Mean overlap of the safe zone by the implant was 49.8% and 40.6%. Mean subsidence was 1.1 ± 1.2 mm, but it did not have any effect on the outcome. In the compression tests, no significant difference (p = 0.468) was found between the two endplate sizes.
INTERPRETATION
Coverage of vertebral body endplates and positioning of implants in the safe zone did not entirely comply with the given recommendations. The amount of endplate coverage had no influence on subsidence or long-term outcomes in daily patient care. On the other hand, correct positioning of the implant may influence its subsidence.
Identifiants
pubmed: 33373970
pii: S0268-0033(20)30370-3
doi: 10.1016/j.clinbiomech.2020.105251
pii:
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
105251Informations de copyright
Copyright © 2020 Elsevier Ltd. All rights reserved.