How much bone support does an anatomic glenoid component need?
Finite element model
backside bone support
glenoid component
loosening
metal backed vs. all polyethylene
Journal
Journal of shoulder and elbow surgery
ISSN: 1532-6500
Titre abrégé: J Shoulder Elbow Surg
Pays: United States
ID NLM: 9206499
Informations de publication
Date de publication:
Apr 2020
Apr 2020
Historique:
received:
07
05
2019
revised:
17
09
2019
accepted:
23
09
2019
entrez:
22
3
2020
pubmed:
22
3
2020
medline:
2
10
2020
Statut:
ppublish
Résumé
An important reason for failure of anatomic total shoulder arthroplasty is glenoid component loosening. We investigated the effect of backside bone support on the risk of failure of a glenoid component. A finite element model was developed. Virtual surgery was performed for 2 types of glenoid components (cemented all polyethylene [PE] vs. metal backed [MB]), both with gradually decreasing backside bone support. Both bone failure and fixation failure were analyzed. The percentages of bone failure and fixation failure in terms of the critical cement volume (CCV) and micromotion-threshold percentage ratio (MTPR) for the PE and MB components, respectively, were defined and compared. For the reference PE model, the percentages of bone failure and fixation failure (CCV) were 17% and 34%, respectively. With eccentric loading for the MB component, the percentages of bone failure and fixation failure (MTPR) were 6% and 3%, respectively. A global increase in failure was observed with decreasing bone support. The increase in fixation failure, starting from the reference values (MTPR vs. CCV), was relatively more pronounced for the MB component (136% vs. 128%). Decreasing backside bone support for an anatomic glenoid component leads to an increased risk of fixation and bone failure. For PE components, decreasing backside support to 95% bone support had only a limited effect. In the case of an MB component, we noticed an increase in micromotion and bone failure already starting from 97% bone support. We conclude that an anatomic glenoid component should always be implanted while maximizing backside bone support.
Sections du résumé
BACKGROUND
BACKGROUND
An important reason for failure of anatomic total shoulder arthroplasty is glenoid component loosening. We investigated the effect of backside bone support on the risk of failure of a glenoid component.
METHODS
METHODS
A finite element model was developed. Virtual surgery was performed for 2 types of glenoid components (cemented all polyethylene [PE] vs. metal backed [MB]), both with gradually decreasing backside bone support. Both bone failure and fixation failure were analyzed. The percentages of bone failure and fixation failure in terms of the critical cement volume (CCV) and micromotion-threshold percentage ratio (MTPR) for the PE and MB components, respectively, were defined and compared.
RESULTS
RESULTS
For the reference PE model, the percentages of bone failure and fixation failure (CCV) were 17% and 34%, respectively. With eccentric loading for the MB component, the percentages of bone failure and fixation failure (MTPR) were 6% and 3%, respectively. A global increase in failure was observed with decreasing bone support. The increase in fixation failure, starting from the reference values (MTPR vs. CCV), was relatively more pronounced for the MB component (136% vs. 128%).
DISCUSSION
CONCLUSIONS
Decreasing backside bone support for an anatomic glenoid component leads to an increased risk of fixation and bone failure. For PE components, decreasing backside support to 95% bone support had only a limited effect. In the case of an MB component, we noticed an increase in micromotion and bone failure already starting from 97% bone support. We conclude that an anatomic glenoid component should always be implanted while maximizing backside bone support.
Identifiants
pubmed: 32197764
pii: S1058-2746(19)30646-9
doi: 10.1016/j.jse.2019.09.019
pii:
doi:
Substances chimiques
Bone Cements
0
Metals
0
Polyethylene
9002-88-4
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
743-754Informations de copyright
Copyright © 2019 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.