Five years in vitro study of (poly vinyl alcohol/poly vinyl pyrrolidone/poly acrylic acid) hydrogel to mimic the knee joint meniscus

In this in vitro study, the developing of novel hydrogels to be used as artificial knee meniscus proceeded for 5 years. These hydrogels were synthesized from polyvinyl alcohol (PVA)/polyvinyl pyrrolidone (PVP)/poly acrylic acid (PAAc) via using irradiation of gamma-rays. Further, the effects of composition, concentration and irradiation dose were investigated. Functional groups and surface morphologies of synthesized hydrogels were characterized by Fourier transform infra red (FTIR) and scanning electron microscopy (SEM). The swelling (%), gelation (%), mass stability (%) and the mechanical tests for compression and stress-relaxation were studied. Factorial design was also used to investigate the relative significance of synthesis factors on the hydrogel properties such swelling, gelation and yield stress. The mechanical tests of PVA/PVP/PAAc hydrogel showed that the yield stress is similar to human meniscus. Therefore, the results suggest that it is possible to use PVA/PVP/PAAc hydrogel to compensate for knee meniscus function. Copyright (c) 2014 John Wiley & Sons, Ltd.