Polyethylene Dual Mobility Liners Show Minimal Polyethylene Changes in Early Retrievals.
crosslink density
dual mobility hip
highly cross-linked polyethylene
implant analysis
oxidation
Journal
The Journal of arthroplasty
ISSN: 1532-8406
Titre abrégé: J Arthroplasty
Pays: United States
ID NLM: 8703515
Informations de publication
Date de publication:
06 2023
06 2023
Historique:
received:
20
12
2022
revised:
21
02
2023
accepted:
26
02
2023
medline:
23
5
2023
pubmed:
7
3
2023
entrez:
6
3
2023
Statut:
ppublish
Résumé
Dual mobility (DM) liners were introduced to reduce instability in total hip arthroplasty. They were found to allow for motion predominantly at the femoral head and the inner bearing of the acetabular liner; however, little is known if this motion is sufficient to alter polyethylene material characteristics. We assessed cross-link (XL) density and oxidation index (OI) measurements of the inner and outer bearing articulations. Thirty-seven DM liners were collected with a duration of implantation greater than 2 years. Clinical and demographic data were collected from a chart review. A cylinder was cored from the apex of each liner and cut into 4.5 mm long inner and outer diameter segments for XL density swell ratio testing. The OI was measured from sagittal 100 μm microtome slices using Fourier transform infrared spectroscopy. Student's t-tests were used to determine differences in OI and XL density between the bearings. Spearman's correlation assessed relationships between patient demographics, OI, and XL density. Duration of implantation for the cohort was a mean of 35 (range, 24-96) months. The inner and outer bearing had similar median XL densities (0.17 mol/dm Small differences were found in oxidation between the inner and outer bearing of the DM construct. Failures at an average of 3 years indicate low levels of oxidation, unlikely to impact the mechanical properties of the material.
Sections du résumé
BACKGROUND
Dual mobility (DM) liners were introduced to reduce instability in total hip arthroplasty. They were found to allow for motion predominantly at the femoral head and the inner bearing of the acetabular liner; however, little is known if this motion is sufficient to alter polyethylene material characteristics. We assessed cross-link (XL) density and oxidation index (OI) measurements of the inner and outer bearing articulations.
METHODS
Thirty-seven DM liners were collected with a duration of implantation greater than 2 years. Clinical and demographic data were collected from a chart review. A cylinder was cored from the apex of each liner and cut into 4.5 mm long inner and outer diameter segments for XL density swell ratio testing. The OI was measured from sagittal 100 μm microtome slices using Fourier transform infrared spectroscopy. Student's t-tests were used to determine differences in OI and XL density between the bearings. Spearman's correlation assessed relationships between patient demographics, OI, and XL density. Duration of implantation for the cohort was a mean of 35 (range, 24-96) months.
RESULTS
The inner and outer bearing had similar median XL densities (0.17 mol/dm
CONCLUSION
Small differences were found in oxidation between the inner and outer bearing of the DM construct. Failures at an average of 3 years indicate low levels of oxidation, unlikely to impact the mechanical properties of the material.
Identifiants
pubmed: 36878437
pii: S0883-5403(23)00199-7
doi: 10.1016/j.arth.2023.02.068
pii:
doi:
Substances chimiques
Polyethylene
9002-88-4
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
1172-1176Informations de copyright
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