Mezaki Takahiro
Department of Neurology, Sakakibara Hakuho Hospital, 5630 Sakakibara-cho, Tsu City, Mie 514-1251, Japan.
Med Hypotheses. 2007;69(6):1309-12. doi: 10.1016/j.mehy.2007.03.014. Epub 2007 Jun 4.
Dystonia is defined as a syndrome of sustained muscle contractions, frequently causing twisting and repetitive movements, or abnormal postures. Although this definition comprises an essential feature of dystonia, the clinical observation indicates that there is an additional aspect of dystonia; failure to adequately activate muscles required for specific movement, exemplified by the lack of contractions of the levator palpebrae superioris muscles in apraxia of lid opening, as well as by inability to activate appropriate muscles in cervical dystonia or in the paretic form of writer's cramp, and possibly by dropped head syndrome or camptocormia seen in parkinsonian patients without apparent truncal dystonia or rigidity. Taking this "negative dystonia" into consideration, the author proposes a revised definition of dystonia as a symptom characterized by the central non-paretic loss of voluntary control of muscle activities, which may result in either excessive or deficient contractions of muscles, frequently causing twisting and repetitive movements, limitation of movements, or abnormal postures.
肌张力障碍被定义为一种持续肌肉收缩的综合征，常导致扭曲和重复性动作，或异常姿势。尽管这一定义包含了肌张力障碍的一个基本特征，但临床观察表明，肌张力障碍还有另外一个方面；即无法充分激活特定运动所需的肌肉，例如睁眼失用症中提上睑肌缺乏收缩，以及颈部肌张力障碍或书写痉挛的麻痹形式中无法激活适当的肌肉，还可能表现为帕金森病患者中出现的低头综合征或躯干前屈症，而这些患者并无明显的躯干肌张力障碍或僵硬。考虑到这种“阴性肌张力障碍”，作者提出了肌张力障碍的修订定义，即一种以中枢性非麻痹性肌肉活动自主控制丧失为特征的症状，这可能导致肌肉过度或不足收缩，常引起扭曲和重复性动作、运动受限或异常姿势。
