Department of Physical Therapy, Faculty of Comprehensive Rehabilitation, Osaka Prefecture University, 3-7-30 Habikino, Habikino city, Osaka 583-8555, Japan.
Muscle Nerve. 2010 May;41(5):694-701. doi: 10.1002/mus.21567.
Although numerous studies have aimed to elucidate the mechanisms used to repair the structure and function of injured skeletal muscles, it remains unclear how and when movement recovers following damage. We performed a temporal analysis to characterize the changes in movement, muscle function, and muscle structure after muscle injury induced by the drop-mass technique. At each time-point, movement recovery was determined by ankle kinematic analysis of locomotion, and functional recovery was represented by isometric force. As a histological analysis, the cross-sectional area of myotubes was measured to examine structural regeneration. The dorsiflexion angle of the ankle, as assessed by kinematic analysis of locomotion, increased after injury and then returned to control levels by day 14 post-injury. The isometric force returned to normal levels by day 21 post-injury. However, the size of the myotubes did not reach normal levels, even at day 21 post-injury. These results indicate that recovery of locomotion occurs prior to recovery of isometric force and that functional recovery occurs earlier than structural regeneration. Thus, it is suggested that recovery of the movement and function of injured skeletal muscles might be insufficient as markers for estimating the degree of neuromuscular system reconstitution.
虽然有许多研究旨在阐明修复受损骨骼肌结构和功能所使用的机制，但运动在损伤后如何以及何时恢复仍然不清楚。我们进行了时间分析，以描述在使用落体技术诱导肌肉损伤后运动、肌肉功能和肌肉结构的变化。在每个时间点，通过运动的踝关节运动学分析来确定运动恢复，通过等长力来表示功能恢复。作为组织学分析，测量肌管的横截面积以检查结构再生。通过运动的踝关节运动学分析评估的背屈角度在损伤后增加，然后在损伤后 14 天恢复到对照水平。等长力在损伤后 21 天恢复到正常水平。然而，即使在损伤后 21 天，肌管的大小也没有达到正常水平。这些结果表明，运动的恢复先于等长力的恢复，功能的恢复早于结构的再生。因此，建议将受伤骨骼肌的运动和功能的恢复作为估计运动神经元系统重建程度的标志物可能不够充分。
