Do Articular Surfaces of Dual Mobility Hips Have More Wear and Friction? An In Vitro Investigation.
▪
Journal
The Journal of arthroplasty
ISSN: 1532-8406
Titre abrégé: J Arthroplasty
Pays: United States
ID NLM: 8703515
Informations de publication
Date de publication:
07 2023
07 2023
Historique:
received:
05
12
2022
revised:
14
04
2023
accepted:
16
04
2023
medline:
9
6
2023
pubmed:
28
4
2023
entrez:
27
4
2023
Statut:
ppublish
Résumé
Larger head-to-neck ratio of dual mobility (DM) hip arthroplasties provide greater range of motion/less risk of dislocation, but raise concerns for high wear and friction. We measured in vitro, the wear rates of contemporary DM hips with highly cross-linked ultra high molecular weight polyethylene (UHWMPE), where it came from, and their frictional torques. Hip simulators were used to compare the wear of DM to fixed-bearing (FB) designs of 2 different implants. Each of 8 different configurations underwent millions of simulated walking cycle tests, some as full DM, some as FB controls, some DM with the outer-articulation deliberately immobilized, and some the inner. Wear and 3-dimensional-frictional torques were measured and friction independent of size was deduced. The DM hips produced lower wear and friction-torque than the FB hips. The DM wear during walking gait comes mostly from the smaller inner articular surface. If the outer surface was immobilized, the wear and torque of the inner alone would be small, but the full DM (inner and outer free-to-move) wear and torque were smallest of all. Friction measurements expectedly showed larger hips having higher frictional torques, but the DM showed the lowest, again because its motion was mostly the smaller inner articulation; smaller than even a modern fixed-bearing hip. The DM hips appear to combine the benefits of greater range of motion and less impingement of larger hips, with the lower wear and friction of smaller FB hips, with some benefits compromised if the outer or inner articulations are immobilized.
Sections du résumé
BACKGROUND
Larger head-to-neck ratio of dual mobility (DM) hip arthroplasties provide greater range of motion/less risk of dislocation, but raise concerns for high wear and friction. We measured in vitro, the wear rates of contemporary DM hips with highly cross-linked ultra high molecular weight polyethylene (UHWMPE), where it came from, and their frictional torques.
METHODS
Hip simulators were used to compare the wear of DM to fixed-bearing (FB) designs of 2 different implants. Each of 8 different configurations underwent millions of simulated walking cycle tests, some as full DM, some as FB controls, some DM with the outer-articulation deliberately immobilized, and some the inner. Wear and 3-dimensional-frictional torques were measured and friction independent of size was deduced.
RESULTS
The DM hips produced lower wear and friction-torque than the FB hips. The DM wear during walking gait comes mostly from the smaller inner articular surface. If the outer surface was immobilized, the wear and torque of the inner alone would be small, but the full DM (inner and outer free-to-move) wear and torque were smallest of all. Friction measurements expectedly showed larger hips having higher frictional torques, but the DM showed the lowest, again because its motion was mostly the smaller inner articulation; smaller than even a modern fixed-bearing hip.
CONCLUSION
The DM hips appear to combine the benefits of greater range of motion and less impingement of larger hips, with the lower wear and friction of smaller FB hips, with some benefits compromised if the outer or inner articulations are immobilized.
Identifiants
pubmed: 37105329
pii: S0883-5403(23)00390-X
doi: 10.1016/j.arth.2023.04.034
pii:
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
S265-S273Informations de copyright
Copyright © 2023 Elsevier Inc. All rights reserved.