Karita Tetsuya, Matsuura Akihiro, Kondo Yoshihiro, Tomimura Kohta, Nakada Nao, Mori Futoshi
aDepartment of Rehabilitation, Daisen Rehabilitation Hospital, Tottori bDepartment of Occupational Therapy, Faculty of Health and Welfare, Graduate School of Comprehensive Scientific Research, Prefectural University of Hiroshima, Mihara, Japan.
Neuroreport. 2017 Nov 8;28(16):1092-1096. doi: 10.1097/WNR.0000000000000891.
The short-term joint immobilization induces a decrease of corticospinal excitability; however, detailed time course of the immobilization-induced central nervous system changes and their extent have not yet been clarified. To evaluate the time course of changes in corticospinal excitability during forearm/hand immobilization for 24 h and investigate the effect on muscle strength, adhesive casting tape was used to immobilize the nondominant forearm/hand. The amplitude of the motor-evoked potential of the flexor pollicis brevis muscle induced by transcranial magnetic stimulation was measured during immobilization and after cast removal. The muscle strength was evaluated after the termination of immobilization. The resting motor-evoked potential recorded from flexor pollicis brevis muscle showed a significant decrease 3 h after initiation of immobilization and gradually declined further until the end of immobilization. It then increased over 2 h after cast removal, but was still significantly below baseline. However, no significant difference from baseline was observed at 3 h. Both pinch power and integrated electromyogram were significantly reduced by immobilization, and then gradually returned to baseline after the cast was removed. These results indicate that short-term forearm/hand immobilization rapidly reduces corticospinal excitability, and this change is rapidly reversed after resumption of movement.
短期关节固定会导致皮质脊髓兴奋性降低；然而，固定引起的中枢神经系统变化的详细时间进程及其程度尚未明确。为了评估前臂/手部固定24小时期间皮质脊髓兴奋性的变化时间进程，并研究其对肌肉力量的影响，使用粘性绷带固定非优势前臂/手部。在固定期间和拆除绷带后，测量经颅磁刺激诱发的拇短屈肌运动诱发电位的幅度。在固定结束后评估肌肉力量。拇短屈肌记录的静息运动诱发电位在固定开始后3小时显著降低，并在固定结束前进一步逐渐下降。拆除绷带后，它在2小时内升高，但仍显著低于基线。然而，在3小时时未观察到与基线有显著差异。捏力和肌电图积分均因固定而显著降低，拆除绷带后逐渐恢复到基线水平。这些结果表明，短期前臂/手部固定会迅速降低皮质脊髓兴奋性，并且这种变化在恢复运动后会迅速逆转。
