The morphological basis of increased stiffness of rabbit tibialis anterior muscles during surgical limb‐lengthening
The morphological basis of increased stiffness of rabbit tibialis anterior muscles during surgical limb‐lengthening
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肢体延长手术过程中兔胫骨前肌僵硬度增加的形态学基础
DOI：
10.1046/j.1469-7580.1998.19310131.x
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发表时间：
1998
影响因子：
2.4
通讯作者：
G. Goldspink
中科院分区：
文献类型：
--
作者：
P. Williams;P. Kyberd;H. Simpson;J. Kenwright;G. Goldspink
当兔子的胫骨前肌在手术肢体牵拉过程中逐渐拉伸时，只要以适当的速率进行拉伸，肌肉纤维就会通过添加新的连续肌节而延长。然而，尽管明显适应了新的功能长度，但关节活动范围却大大减少。在这项研究中，我们首先测量了关节运动范围内分散的肌肉产生的被动张力，然后定量测量了肌内膜和肌周结缔组织的含量。结果发现，在所有踝关节角度大于 90° 的情况下，分散肌肉产生的被动张力大于对侧和假手术对照组。图像分析表明，与假手术对照组的肌肉相比，由于 III 型胶原蛋白沉积增加，分散肌肉中胶原蛋白与收缩材料的比例有所增加。扫描电子显微镜显示，在分散的肌纤维周围存在致密的肌周组织。结缔组织成分的这些定量和定性变化可以解释生理测量表明的硬度增加。看起来，在分散的肌肉中，结缔组织成分比收缩成分更不容易适应，长时间的拉伸会导致肌周和肌内膜网络受损，随后发生纤维化和肌肉顺应性丧失。这些变化可能有助于解释在接受肢体延长手术的患者的四肢分心以及导致肌肉挛缩的其他情况下注意到的运动范围的丧失。
When the tibialis anterior muscle of the rabbit is progressively stretched during surgical limb distraction, the muscle fibres lengthen by addition of new serial sarcomeres, provided that stretch is carried out at an appropriate rate. However, in spite of the apparent adaptation to the new functional length, range of joint movement is greatly decreased. In this study we have first, made measurements of the passive tension developed by distracted muscles over the range of joint movement and secondly made quantitative measurements of endomysial and perimysial connective tissue content. It was found that at all ankle joint angles greater than 90°, the passive tension developed by the distracted muscles was greater than both contralateral and sham‐operated controls. Image analysis showed that the ratio of collagen to contractile material was increased in distracted muscles compared with muscles from sham‐operated controls, due to increased deposition of collagen type III. Scanning electron microscopy showed the presence of a dense perimysial weave surrounding the distracted muscle fibres. These quantitative and qualitative changes in the connective tissue component could account for the increased stiffness demonstrated by the physiological measurements. It would seem that in distracted muscle the connective tissue element adapts less readily than the contractile component, with prolonged stretch leading to damage to the perimysial and endomysial network, with subsequent fibrosis and loss of muscle compliance. Such changes could help explain the loss of range of movement noted in the distracted limbs of patients undergoing surgical limb‐lengthening and in other conditions that result in muscle contractures.