P.096 Evaluation of Poly Vinyl Alcohol Cryogel (PVA-C) composites for mimicking biomechanical properties of the lumbar interverterbral disc. (2nd June 2017)

• Record Type: Journal Article
• Authors: Wang, BH; Gurr, K; Bailey, C; Campbell, G
• Is Part Of: Canadian journal of neurological sciences. Volume 44(2017)Supplement 2
• Page Start: S38
• Page End: S38
• Publication Date: 2017-06-02
• Subjects: Neurology -- Periodicals; Nervous system -- Surgery -- Periodicals; Electronic journals; 616.8
• DOI: 10.1017/cjn.2017.180
• Languages: English
• ISSNs: 0317-1671

Abstract

Abstract : Background: Current lumbar intervertebral disc prostheses provide suboptimal symptom relief with little natural load-cushioning. PVA-C is a promising biocompatible material, and our previous study finds that it can closely mimic the properties of nucleus pulposus. However, pure PVA-C does not possess adequate stiffness to mimic the annulus fibrosus.Methods: Composite particle-reinforced PVA-C formulations were tested to identify methods that could increase the elastic modulus. This included: sephadex, hydroxyapatite (stock) and hydroxyapatite (in-solution synthesis). All formulations were tested using 15% PVA-C and 5% reinforcing agent. Indentation and durometer tests were performed as well as simple compression, compressive stress relaxation and creep.Results: Indentation and durometer results did not clearly reveal any specific formulations that significantly improved stiffness. The addition of in-solution synthesized hydroxyapatite resulted in 1.15 to 2 time increase in elastic modulus (0.3-0.9 MPa) and associated decrease in stress relaxation and creep. The addition of stock hydroxyapatite and spehadex (G100f and G50sf) lowered the elastic modulus and increased stress relaxation and creep.Conclusions: In-solution synthesized hydroxyapatite is the only particle-reinforced composite PVA-C formulation that exhibited greater stiffness than pure PVA-C. The elastic modulus will need to be increased by 5-10x to adequately mimic the annulus fibrosus. A fiber-reinforced composite will likely be needed to accomplish this.