The experimental study for the explication of mechanism and therapy on the joint contracture

研究1：关节挛缩发生机制的实验研究制动常伴随着肌肉弹性的降低。这种情况被称为肌肉挛缩，但其机制尚不清楚。我们研究了踝关节活动度，被动张力，肌节长度，胶原纤维的安排在肌内膜，和透明质酸在肌肉组织中的变化1，2，4，8，和12周后制动大鼠比目鱼肌缩短的位置。踝关节活动度随制动时间延长而降低。静止肌肉的被动张力增加了。肌节长度在制动后1周缩短，但在制动后2、4、8和12周没有进一步变化。制动后1、2周肌内膜胶原纤维排列为纵行，制动后4、8、12周肌内膜胶原纤维排列为环行，制动后1、2周肌内膜胶原纤维排列为纵行，制动后4、8、12周肌内膜胶原纤维排列为环行，制动后1、2周肌内膜胶原纤维排列为纵行，制动后4、8、12周肌内膜胶原纤维排列为环行。 ...更多信息 制动后1周增加，但在第2、4、8和12周保持相同水平。组织化学上，固定肌组织的肌内膜中透明质酸的染色比对照组织更强和更广。肌肉组织中透明质酸的增加可能导致肌肉僵硬，但透明质酸与肌肉挛缩机制的关系尚不清楚。结果表明，垫肌挛缩开始于制动后1周，并随着制动时间的延长而增加。因此，肌肉挛缩在固定的早期阶段受到缩短的肌纤维的影响，之后胶原蛋白通过肌内膜中的原纤维排列变得更加周向而适应。这种胶原纤维排列的改变可能导致制动后期的晚期肌肉挛缩。研究二：关节挛缩治疗的实验研究1）确定延长牵拉是否能预防小鼠关节挛缩。发现在持续10分钟的拉伸期间不能防止关节挛缩的进展，并且在持续20分钟或更长的拉伸期间可以防止。但持续30 min的牵拉并不能完全阻止关节挛缩的进展。2）确定长时间牵拉是否改善了固定大鼠比目鱼肌的废用性肌萎缩。18只雄性Wistar大鼠随机分为对照组（n=3）和制动组（n=15）。制动组大鼠踝关节制动4周，分为3组：单纯制动组（I组，n=3）、制动后1周或3周的牵拉训练组（S组，n=6）和制动后1周或3周的自然恢复组（NS组，n=6）。再运动1周后，S组I型肌纤维直径较NS组显著增加。再运动3周后，S组的I型和II型肌纤维直径较NS组显著增加。我们的研究结果表明，延长拉伸诱导恢复废用性肌肉萎缩后，关节挛缩。少

Study 1 : The experimental study for the explication of mechanism on the joint contractureImmobilization is often associated with a decrease in muscle elasticity. This condition is called muscle contracture, but the mechanism is not yet clear. We examined changes in ankle joint mobility, passive tension, sarcomere length, collagen fibril arrangement in the endomysium, and hyaluronic acid in muscular tissue 1, 2, 4, 8, and 12 weeks after immobilization of rat soleus muscles in shortened position. Ankle joint mobility decreased with the duration of immobilization. Passive tension on immobilized muscles had increased. Sarcomere length had shortened 1 week after immobilization, but did not show further change 2, 4, 8, and 12 weeks after immobilization. Collagen fibril arrangement in the endomysium 1 and 2 weeks after immobilization was longitudinal to the axis of the muscle fibers, whereas 4, 8, and 12 weeks after immobilization it was circumferential.Hyaluronic acid in muscular tissue had … More increased 1 week after immobilization but remained at the same level at weeks 2, 4, 8, and 12. Histochemically, hyaluronic acid in the endomysium of immobilized muscular tissue was stained more strongly and widely than that in the control tissue. Increased hyaluronic acid in muscular tissue may induce muscle stiffness, but the significance of how hyaluronic acid is related to the mechanism of muscle contracture was not clear. The findings suggest mat muscle contracture started 1 week after immobilization and increased with the length of immobilization. Consequently, muscle contracture is affected by the shortening muscle fibers during the early stage of immobilization, after which the collagen adapts by the fibril arrangement in the endomysium becoming more circumferential. This change in collagen fibril arrangement may cause advanced muscle contracture in the late stage of immobilization.Study 2 : The experimental study for the explication of therapy on the joint contracture1) To determine whether prolonged stretching is preventing for joint contracture in mice. It was found that progression of joint contracture can not be prevented in periods of stretch lasting 10 min, and can prevent in periods of stretch lasting 20 min or more. But the progression of joint contracture can not completely prevented in periods of stretch lasting 30 min.2) To determine whether prolonged stretching is ameliorating for disuse muscle atrophy in immobilized rat soleus muscles. Eighteen male Wistar rats were divided randomly into control (n=3) and immobilization (n=15) groups. The immobilization groups rats were immobilized on ankle joint for 4 weeks, animals were divided into three groups : immobilization alone (group I, n=3), stretch training for 30 min/day for 1or 3 weeks after remobilization (group S, n=6), and spontaneous recovery (non stretch training) for 1 or 3 weeks after remobilization (group NS, n=6). After 1 week of remobilization, muscle fiber diameters for type I fibers in group S had increased significantly compared with group NS. After 3 weeks of remobilization, muscle fiber diameters for types I and II fibers in group S had increased significantly compared with group NS. Our findings suggest that prolonged stretching induces recovery from disuse muscle atrophy after joint contracture. Less