Damage in total knee replacements from mechanical overload.
Damage in total knee replacements from mechanical overload.
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DOI：
10.1016/j.jbiomech.2016.05.014
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发表时间：
2016-07-05
影响因子：
2.4
通讯作者：
Mann KA
中科院分区：
文献类型：
--
作者：
Zimmerman WF;Miller MA;Cleary RJ;Izant TH;Mann KA
全膝关节置换术(TKR)后在日常生活活动中作用于膝关节的机械载荷最近被用仪器化的TKR测量。使用一系列死后取回的TKR结构，我们调查了这些机械载荷是否会导致胫骨内种植体骨界面或支撑骨的损伤。18个使用年限0~22年的骨水泥整块胫骨假体在1~10倍体重的轴向压缩下加载，利用数字图像相关技术测量加载和卸载过程中的骨应变和界面微运动。当微运动超过150μm或压缩骨应变超过7300με时，认为发生失败。结果表明，所有回收的标本都有足够的骨强度来支持大多数日常生活活动，但~40%的标本在较大的生理负荷下可能面临风险，这些负荷可能会发生更高的冲击，如慢跑或绊倒。植入时年龄较低的供者的盘骨微动(回归模型R2=0.48，p=0.025)更大(p=0.0092)。近端骨骼应变(模型R2=0.46，p=0.03)对于服役时间较长的供者来说更大(p=0.021)。服务时间较长(p=0.005)和种植体周围骨密度较低(p=0.049)的供者远端骨应变较大(模型R2=0.58p=0.005)。单一或重复性质的高机械过载可能是全关节置换术无菌性松动的始动因素，应避免，以延长植入物的寿命。
The mechanical loads acting across the knee joint following total knee replacements (TKR) during activities of daily living have recently been measured using instrumented TKRs. Using a series of postmortem retrieved TKR constructs we investigated whether these mechanical loads could result in damage to the implant bone interface or supporting bone in the tibia. Eighteen cemented en bloc tibial components (0 to 22 years in service) were loaded under axial compression in increments from 1 to 10 times body weight and digital image correlation was used to measure bone strain and interface micromotion during loading and unloading. Failure was considered to occur when micromotion exceeded 150 μm or compressive bone strain exceeded 7300 με. The results show that all retrieved specimens had sufficient bone strength to support most activities of daily living, but ~40% would be at risk under larger physiologic loads that might occur secondary to a higher impacts such as jogging or a stumble. The tray-bone micromotion (regression model R2=0.48, p=0.025) was greater for donors with lower age at implantation (p=0.0092). Proximal bone strain (model R2=0.46, p=0.03) was greater for donors with longer time in service (p=0.021). Distal bone strain (model R2=0.58, p=0.005) was greater for donors with more time in service (p=0.0054) and lower peri-implant BMD (p=0.049). High mechanical overload of a single or repetitive nature may be an initiating factor in aseptic loosening of total joint arthroplasties and should be avoided in order to prolong the life of the implant.