人体小腿肌腱生物材料力学特征实验研究

Experimental Study on the Bio-mechanical Characteristics of Human Lower Leg Tendon

目的:人体小腿肌腱损伤后的防治、修复、人工材料替换等需要大量的生物材料力学特征方面的实验数据作为其参考依据。方法:使用德国产Zwick万能材料实验机,对小腿9种72条成人新鲜小腿肌腱进行"一维拉伸破坏试验",并对实验数据进行统计学处理。结果:(1)当应变为0-5%范围时,形变随拉伸应力改变较小,属于曲线的"坡脚区";当应变为8%-16%范围时,应力随应变增大而增大,属于曲线的"直线区";当应变达到20%左右时,拉伸应力则随应变增大而减小。(2)小腿肌腱之间极限应变没有显著性差异;跟腱极限应力明显小于趾长伸肌腱、趾长屈肌腱、拇长伸肌腱与拇长伸肌腱(P<0.05)。(3)部分小腿肌腱之间拉伸刚度与弹性模量有显著性差异(P<0.05)。结论:(1)小腿肌腱与前臂肌腱均是以规则致密结缔组织为主构成,故其"应力—应变曲线"也呈现基本相同的特征。(2)从小腿各肌腱极限应变指标对比结果差异不明显可以推断小腿肌腱抵抗最大负荷的能力基本相同;跟腱由于其截面积大,应力呈现分散现象,故极限应力最小。(3)跟腱的拉伸刚度较大,从生物材料上保证其能够承受踝关节完成高频率、大强度、较大运动幅度的背屈运动。(4)肌腹强大的肌腱主要通过肌肉收缩力使其产生弹性变形,而肌腹较小的肌腱主要通过自身弹性变形满足承担功能的需要。

Objective：Study of the bio-mechanical properties on human lower leg tendon provides theoretical basis for injury prevention, repair and artificial materials replacement. Methods：The Zwick universal material testing ma-chine from Germany was used to conduct one dimensional destructive test on 9 kinds of tendon from 72 cases of adult fresh lower leg, and the experimental data were statistically analyzed. Results：（1） When the Strain falls in the 0 ~ 5% range, which is the “toe region” of the curve, the deformation changes little with the tensile stress. In the 8% ~ 16% strain range, which is the“Linear region” of the curve, the tensile stress increases with the strain increase. When the deformation reaches around 20%, tensile stress decreases with increasing strain. （2） There is no significant difference in the ultimate strain indicators among the 9 kinds of tendon, while the ultimate stress indicators of the Achilles tendon is significantly smaller than that of the extensor ten-don, the flexor tendon, and the hallux longus tendon（P〈0. 05）. （3） There are significant differences between the tensile stiffness and elastic modulus for some of the 9 kinds of tendon. （P〈0. 05） Conclusion：（1） There is little difference in the stress vs. strain curves for 9 kinds of lower leg tendon, and the curves are basically the same as those for the forearm tendon, which shows that the tendons of the main structure in the dense connec-tive tissue are basically the same. （2） The difference of the limit strain indexes of the leg tendon is not obvi-ous, so it is concluded that the ability of the calf tendon to resist the maximum load is basically the same. Be-cause of the large area of the Achilles tendon, the stress is scattered, so the ultimate stress is the least. （3） The tensile stiffness of the Achilles tendon is large, which, in perspective of the biological material mechanics , en-sures that the ankle joint can withstand the the back flexion movement of high frequency, high intensity and great amplitude. （4） Strong muscle belly produces elastic deformation mainly through the muscle contraction force, while tendon with smaller belly muscle meets the needs of the function mainly through its own elastic de-formation capacity.