Krarup C, Horowitz S H
Muscle Nerve. 1979 Nov-Dec;2(6):465-77. doi: 10.1002/mus.880020608.
Electrical and mechanical responses were evoked in the elbow flexors (EFs) of normal subjects and myopathy patients by maximal stimulation of the musculocutaneous nerve by a wire electrode in the axilla. In normals, the decrement in the mechanical responses during short trains of twitches was small (10%). The potentiation during a staircase decreased with increasing frequency of stimuli, but the potentiation 30 sec after the 100-sec staircase was the same at all frequencies. Posttetanic potentiation was twice as large as the maximal potentiation attained during the staircase. The staircase phenomenon probably results from two opposing events, diminution and potentiation. Findings in 11 patients with myopathy varied according to the severity of involvement. Slight weakness of the EFs was associated with an increased twitch:tetanus ratio, decreased tetanic tension, and decrease in the staircase and posttetanic potentiation. Additionally, severe weakness of the EFs was associated with a diminution in twitch tension.
通过腋窝处的线状电极对肌皮神经进行最大刺激，在正常受试者和肌病患者的肘屈肌（EFs）中诱发电反应和机械反应。在正常人中，短串抽搐期间机械反应的递减很小（10%）。阶梯现象期间的增强随着刺激频率的增加而降低，但在100秒阶梯刺激后30秒的增强在所有频率下都是相同的。强直后增强是阶梯现象期间达到的最大增强的两倍。阶梯现象可能是由两个相反的事件，即递减和增强导致的。11例肌病患者的结果根据受累严重程度而有所不同。EFs轻度无力与抽搐：强直比值增加、强直张力降低以及阶梯现象和强直后增强降低有关。此外，EFs严重无力与抽搐张力降低有关。
