Williams P, Simpson H, Kyberd P, Kenwright J, Goldspink G
Department of Biological Sciences, University of Hull, England.
Anat Rec. 1999 May 1;255(1):78-83. doi: 10.1002/(SICI)1097-0185(19990501)255:1<78::AID-AR9>3.0.CO;2-M.
Surgical lengthening of limbs often results in loss of range of joint movement and this has been shown to be associated with an increase in passive tension and an increase in collagen content of the muscles. In this study, we have investigated the length/tension properties and the connective tissue component of muscle distracted at three different rates in order to determine whether low rates of distraction would enable the connective tissue component, as well as the contractile component (number of serial sarcomeres), to adapt more completely to the increased functional length of the muscle and thus lead to improved range of joint movement. It was found that loss of range of movement varied with rate of distraction. At the low rate, there was no change in the passive tension or collagen content compared to muscles from sham-operated animals, and range of movement was significantly greater than at the other rates. At the medium rate, although the muscles showed good adaptation in terms of serial sarcomere number, passive tension and collagen content was increased and range of movement reduced, indicating that changes in the connective tissue component are important factors in loss of joint movement. In the case of muscle distracted at a high rate, failure of the muscle fibres to add on sufficient sarcomeres, combined with changes in the connective tissue, resulted in almost total loss of joint movement.
肢体的外科延长术常常导致关节活动范围的丧失，并且已表明这与被动张力增加以及肌肉胶原蛋白含量增加有关。在本研究中，我们研究了以三种不同速率牵张的肌肉的长度/张力特性以及结缔组织成分，以确定低牵张速率是否能使结缔组织成分以及收缩成分（连续肌节的数量）更完全地适应肌肉增加的功能长度，从而导致关节活动范围得到改善。结果发现，活动范围的丧失随牵张速率而变化。在低速率下，与假手术动物的肌肉相比，被动张力或胶原蛋白含量没有变化，并且活动范围明显大于其他速率时的情况。在中速率下，尽管肌肉在连续肌节数量方面表现出良好的适应性，但被动张力和胶原蛋白含量增加，活动范围减小，这表明结缔组织成分的变化是关节活动丧失的重要因素。在高速率牵张的肌肉的情况下，肌纤维未能添加足够的肌节，再加上结缔组织的变化，导致关节活动几乎完全丧失。
