人工关节材料生物摩擦声学测试研究

硬相对硬相人工关节因其低磨损率的特点,更为适用于日常活动量较大的年轻患者群体。而在该类关节的术后随访中发现,伴随人体的运动,一部分人工关节会由于摩擦而产生异样噪声,临床发生率为0.7%～20.9%。该现象成因复杂,涉及材料摩擦磨损、不良润滑、人工关节失配以及边缘载荷等因素。针对硬相人工关节在服役中的异响问题,提出生物摩擦学与声学交叉研究方法,建立了人工关节材料的生物摩擦声学测试系统,主要包括人工关节材料摩擦学测试装置、类消声室、以及声压信号测试采集系统,能够实现人工关节材料摩擦学与声学参数的在线测量。基于该系统试验研究ZrO2陶瓷关节材料在去离子水与仿生关节滑液润滑状态下的摩擦声学表现,发现在仿生关节液下得到较好的润滑,存在薄膜润滑情况,摩擦表面呈抛光迹象,声压及声功率值均小于去离子水润滑条件下,且与摩擦因数有较好吻合,异响频率与临床发现更为接近。通过该系统的建立与试验验证,初步探索了人工关节材料的生物摩擦声学的测试方法。

Biotribo-acoustic Study on Artificial Joint Materials

Due to the long service duration time and less inflammatory osteolysis,hard-on-hard artificial joints,such as ceramic-on-ceramic or metal-on-metal joints,are considered more suitable for young and active patients.However,the incidence of squeaking associated with hard-on-hard bearings is variably reported,ranging from 0.7% to 20.9%.Since squeaking is a tribological induced acoustics emission phenomenon,contributing factors may include material friction and wear,loss of lubrication,component malposition,edge loading and impingement.A new biotribologicial and acoustic test methodology is proposed.Testing system,including an artificial joint material tribometer,acoustic acquisition system and a simu-anechoic chamber,is developed for the biotribo-acoustic tests of hard-on-hard artificial joint material.Tribological and acoustic data are acquired on-line synchronously.Via this system,ZrO2 on ZrO2 ceramic artificial joint materials tests are performed under the lubrication of deionized water and biomimetic synovial fluids.Results show that in BSF,both friction coefficient and sound pressure are lower than those in the deionized water.Moreover,film lubrication is provided by the BSF,wear surfaces are much smoother.However,under deionized water lubrication abrasive wear is found.In frequency analysis,the sound frequency observed under BSF lubrication is similar to the clinical squeaking results.Thus,through testing system development and preliminary test validation,a new and effective proposal for biotribo-acoustic methodology for the fundamental study of artificial joint materials is provided.