Usuba M, Akai M, Shirasaki Y, Miyakawa S
Course of Physical Therapy, Department of Health, Tsukuba University of Technology, 4-12-7 Kasuga, Tsukuba, lbaraki 305-0298, Japan.
Clin Orthop Relat Res. 2007 Mar;456:70-8. doi: 10.1097/BLO.0b013e31803212bf.
Tension is necessary to maintain and restore the mechanical properties of soft connective tissues. Conversely, reduced tension states such as produced by immobilization weaken mechanical properties and facilitate joint contracture. We assessed the effect of low torque-long duration stretching to increase the range of motion (ROM) and to restore the mechanical properties of contracted joints in 66 rat knees immobilized for 40 days. After remobilization, we randomly divided the contracted knees into four treatment groups treated with repeated stretches of diverse torques and duration: stretching with low-torque and long-duration, high-torque and short-duration, high-torque and long-duration, low-torque and short duration. We included control and natural recovery groups. Phase lag in all treatment groups recovered to the same range as in the normal controls. Dynamic stiffness, which was not altered by joint immobilization, increased in all treatment groups. Deformation and load to failure improved substantially only in the low-torque and long-duration stretching group. Low-torque and long-duration repeated stretching leads to a greater restoration of ROM with more normal mechanical properties compared to high-torque and short duration stretching.
张力对于维持和恢复软结缔组织的力学性能是必要的。相反，诸如因固定而产生的低张力状态会削弱力学性能并促进关节挛缩。我们评估了低扭矩-长时间拉伸对66只固定40天的大鼠膝关节增加活动范围（ROM）和恢复挛缩关节力学性能的影响。重新活动后，我们将挛缩的膝关节随机分为四个治疗组，用不同扭矩和持续时间的重复拉伸进行治疗：低扭矩-长时间拉伸、高扭矩-短时间拉伸、高扭矩-长时间拉伸、低扭矩-短时间拉伸。我们纳入了对照组和自然恢复组。所有治疗组的相位滞后恢复到与正常对照组相同的范围。动态刚度在关节固定时未改变，在所有治疗组中均增加。仅在低扭矩-长时间拉伸组中，变形和破坏载荷有显著改善。与高扭矩-短时间拉伸相比，低扭矩-长时间重复拉伸能使ROM得到更大程度的恢复，力学性能更接近正常。
