Belanger A Y, McComas A J
J Neurol Neurosurg Psychiatry. 1983 Jul;46(7):625-31. doi: 10.1136/jnnp.46.7.625.
A study has been made of the contractile properties of plantarflexor and dorsiflexor muscles in 25 patients with myotonic dystrophy and in the same number of closely-matched control subjects. As anticipated, the mean torques developed during maximal voluntary contraction and during the isometric twitch were significantly reduced in the patient population, as were the mean amplitudes of the respective maximum muscle compound action potentials (M-waves). There was considerable variation in weakness between patients, however, and in some there was a striking discrepancy between the results for the plantarflexor and dorsiflexor muscles. It was also found that, in both muscle groups, the mean twitch contraction times were significantly shorter in patients than in controls, but no differences could be demonstrated in relation to fatiguability and post-activation of the twitch. Some patients had great difficulty in obtaining full activation of plantarflexor motor units but there was improvement with repeated effort.
对25例强直性肌营养不良患者以及相同数量的年龄、性别匹配的对照者的跖屈肌和背屈肌的收缩特性进行了研究。正如预期的那样，患者组在最大自主收缩和等长单收缩期间产生的平均扭矩显著降低，各自最大肌肉复合动作电位（M波）的平均波幅也显著降低。然而，患者之间的肌无力程度存在相当大的差异，并且在一些患者中，跖屈肌和背屈肌的结果存在显著差异。还发现，在两组肌肉中，患者的平均单收缩收缩时间明显短于对照组，但在疲劳性和单收缩后激活方面没有差异。一些患者在使跖屈肌运动单位完全激活方面存在很大困难，但反复努力后有所改善。
