Effects of repeated crush injuries on motor functional recovery of thesciatic nerve

为探讨反复挤压伤是否对周围神经运动功能恢复有显著影响，每隔1周复制成年大鼠坐骨神经反复挤压伤模型，以坐骨神经SSI、胫骨S前肌纤维大小及纤维再支配为指标评价坐骨神经功能。与单一挤压伤相比，双挤压伤在伤后4周完全恢复，但在伤后6周完全恢复，而三重挤压伤导致再生过程明显迟缓，在实验8周恢复不完全。三次挤压大鼠的肌肉纤维大小在损伤后4周没有恢复到正常范围，尽管一次挤压大鼠的肌肉纤维大小正常。这些结果表明，反复挤压损伤抑制了受损坐骨神经的运动功能恢复，表现为再生延迟和不完全，肌纤维萎缩，神经再支配延迟。

The present study was conducted to examine whether repeated crush injuries have significant effects on motor functional recovery of peripheral nerves.Repeated crush injuries of the sciatic nerve were inflicted on adult rats at 1 -week intervals, and functionality of the sciatic nerve was assessed by the SSI, tibiali s anterior muscle fibers size,and its fiber reinnervation. Compared to single crush injuries, which completely recovered by post-injury week 4, double crush injuries resulted in retarded, but complete recovery by post-injury week 6, whereas triple crush injuries resulted in marked retardation in the regenerative process with incomplete recovery during week 8 of the experimental period. Muscle fiber size for rats with triple crush did not recover to normal range at post-injury week 4, despite its normal size for rats with single crush. These results indicate that repeated crush injuries inhibit motor functional recovery of the damaged sciatic nerve, as evidenced by delayed and incomplete regeneration, atrophied muscle fibers, and delayed reinnervation.