In vitro estimation of reduction in strength and wear resistance of UHMWPE for joint prostheses due to lipid-induced degradation.
In vitro estimation of reduction in strength and wear resistance of UHMWPE for joint prostheses due to lipid-induced degradation.
复制标题
由于脂质诱导的降解，关节假体 UHMWPE 的强度和耐磨性降低的体外评估。
DOI：
10.1002/jbm.b.34641
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Okamoto Y and Haishima Y
中科院分区：
文献类型：
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作者：
Sakoda H;Okamoto Y and Haishima Y
超高相对分子质量聚乙烯(UHMWPE)被用作关节假体的支承表面，并已被报道在体内吸收脂质如角鲨烯(SQ)和胆固醇酯。使用SQ作为模型脂的体外研究表明，这些脂类具有诱导聚合物降解的潜力。然而，脂诱导降解对UHMWPE强度和耐磨性的影响尚不清楚。本研究通过SQ吸附和随后的加速老化来模拟脂质诱导的降解，并通过磨损、疲劳裂纹扩展和分层试验来研究其对UHMWPE强度和耐磨性的影响。研究发现，脂质诱导的降解对疲劳裂纹扩展速率和抗分层性能影响不大。这些结果与以前的报道一致，即脂类诱导的降解局限于表面附近。然而，我们也发现，脂质诱导的降解使未交联型和交联型UHMWPE的磨损率分别提高了2.5和14倍。这些结果表明，由于UHMWPE磨损增加，脂质诱导的降解可能会影响关节置换术的耐久性和长期临床结果。
Ultra‐high molecular weight polyethylene (UHMWPE) is used as a bearing surface of joint prostheses and has been reported to absorb lipids such as squalene (SQ) and cholesterol esters in vivo. These lipids have been suggested by in vitro studies using SQ as a model lipid to have the potential to induce polymer degradation. However, the impact of lipid‐induced degradation on the strength and wear resistance of UHMWPE is unknown. In this study, lipid‐induced degradation was simulated by SQ absorption and subsequent accelerated aging, and its influence on the strength and wear resistance of UHMWPE was investigated using wear, fatigue crack growth, and delamination testing. Lipid‐induced degradation was found to have little impact on fatigue crack growth rates and delamination resistance. These results were consistent with previous reports that lipid‐induced degradation is localized near the surface. However, we also found that lipid‐induced degradation increased the wear rate of both non‐crosslinked and crosslinked UHMWPE by a factor of 2.5 and 14, respectively. These results indicate that lipid‐induced degradation may affect the durability and long‐term clinical outcome of joint replacements due to increased wear of UHMWPE.