An Artificial PVA-BC Composite That Mimics the Biomechanical Properties and Structure of a Natural Intervertebral Disc

Disc herniation is one of the most ubiquitous healthcare problems in modern cities—severe patients eventually require surgical intervention. However, the existing operations—spinal fusion and artificial disc replacement—alter the biomechanics of the spine, leaving much room for improvement. The appr...

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Main Authors: Mengying Yang, Dingding Xiang, Yuru Chen, Yangyang Cui, Song Wang, Weiqiang Liu
Format: Article
Language:English
Published: MDPI AG 2022-02-01
Series:Materials
Subjects:
Online Access:https://www.mdpi.com/1996-1944/15/4/1481
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author Mengying Yang
Dingding Xiang
Yuru Chen
Yangyang Cui
Song Wang
Weiqiang Liu
author_facet Mengying Yang
Dingding Xiang
Yuru Chen
Yangyang Cui
Song Wang
Weiqiang Liu
author_sort Mengying Yang
collection DOAJ
description Disc herniation is one of the most ubiquitous healthcare problems in modern cities—severe patients eventually require surgical intervention. However, the existing operations—spinal fusion and artificial disc replacement—alter the biomechanics of the spine, leaving much room for improvement. The appropriateness of polyvinyl alcohol (PVA) for biomedical applications has been recognised due to its high water content, excellent biocompatibility, and versatile mechanical properties. In this study, a newly-designed PVA–bacterial cellulose (PVA-BC) composite was assembled to mimic both the biomechanics and annular structure of natural intervertebral discs (IVDs). PVA-BC composites of various concentrations were fabricated and tested under unconfined compression and compressive creep in order to acquire the values of the normalised compressive stiffness and whole normalised deformation. The normalised compressive stiffness increased considerably with an increasing PVA concentration, spanning from 1.82 (±0.18) to 3.50 (±0.14) MPa, and the whole normalised deformation decreased from 0.25 to 0.13. Formulations of 40% PVA provided the most accurate mimicry of natural human IVDs in normalised whole deformation, and demonstrated higher dimensional stability. The biocompatible results further confirmed that the materials had excellent biocompatibility. The novel bionic structure and formulations of the PVA-BC materials mimicked the biomechanics and structure of natural IVDs, and ensured dimensional stability under prolonged compression, reducing the risk of impingement on the surrounding tissue. The PVA-BC composite is a promising material for third-generation artificial IVDs with integrated construction.
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spelling doaj.art-ba8cd5e5d9884470b1a322a41cf4d6682023-11-23T20:53:58ZengMDPI AGMaterials1996-19442022-02-01154148110.3390/ma15041481An Artificial PVA-BC Composite That Mimics the Biomechanical Properties and Structure of a Natural Intervertebral DiscMengying Yang0Dingding Xiang1Yuru Chen2Yangyang Cui3Song Wang4Weiqiang Liu5Department of Mechanical Engineering, Tsinghua University, Beijing 100084, ChinaState Key Laboratory of Tribology, Tsinghua University, Beijing 100084, ChinaDepartment of Mechanical Engineering, Tsinghua University, Beijing 100084, ChinaDepartment of Mechanical Engineering, Tsinghua University, Beijing 100084, ChinaBiomechanics and Biotechnology Lab, Research Institute of Tsinghua University in Shenzhen, Shenzhen 518057, ChinaDepartment of Mechanical Engineering, Tsinghua University, Beijing 100084, ChinaDisc herniation is one of the most ubiquitous healthcare problems in modern cities—severe patients eventually require surgical intervention. However, the existing operations—spinal fusion and artificial disc replacement—alter the biomechanics of the spine, leaving much room for improvement. The appropriateness of polyvinyl alcohol (PVA) for biomedical applications has been recognised due to its high water content, excellent biocompatibility, and versatile mechanical properties. In this study, a newly-designed PVA–bacterial cellulose (PVA-BC) composite was assembled to mimic both the biomechanics and annular structure of natural intervertebral discs (IVDs). PVA-BC composites of various concentrations were fabricated and tested under unconfined compression and compressive creep in order to acquire the values of the normalised compressive stiffness and whole normalised deformation. The normalised compressive stiffness increased considerably with an increasing PVA concentration, spanning from 1.82 (±0.18) to 3.50 (±0.14) MPa, and the whole normalised deformation decreased from 0.25 to 0.13. Formulations of 40% PVA provided the most accurate mimicry of natural human IVDs in normalised whole deformation, and demonstrated higher dimensional stability. The biocompatible results further confirmed that the materials had excellent biocompatibility. The novel bionic structure and formulations of the PVA-BC materials mimicked the biomechanics and structure of natural IVDs, and ensured dimensional stability under prolonged compression, reducing the risk of impingement on the surrounding tissue. The PVA-BC composite is a promising material for third-generation artificial IVDs with integrated construction.https://www.mdpi.com/1996-1944/15/4/1481PVA-BCintervertebral discbiomechanicscreepunconfined compression
spellingShingle Mengying Yang
Dingding Xiang
Yuru Chen
Yangyang Cui
Song Wang
Weiqiang Liu
An Artificial PVA-BC Composite That Mimics the Biomechanical Properties and Structure of a Natural Intervertebral Disc
Materials
PVA-BC
intervertebral disc
biomechanics
creep
unconfined compression
title An Artificial PVA-BC Composite That Mimics the Biomechanical Properties and Structure of a Natural Intervertebral Disc
title_full An Artificial PVA-BC Composite That Mimics the Biomechanical Properties and Structure of a Natural Intervertebral Disc
title_fullStr An Artificial PVA-BC Composite That Mimics the Biomechanical Properties and Structure of a Natural Intervertebral Disc
title_full_unstemmed An Artificial PVA-BC Composite That Mimics the Biomechanical Properties and Structure of a Natural Intervertebral Disc
title_short An Artificial PVA-BC Composite That Mimics the Biomechanical Properties and Structure of a Natural Intervertebral Disc
title_sort artificial pva bc composite that mimics the biomechanical properties and structure of a natural intervertebral disc
topic PVA-BC
intervertebral disc
biomechanics
creep
unconfined compression
url https://www.mdpi.com/1996-1944/15/4/1481
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