The secondarydystonia is caused by brain trauma, infection, or special stimulation of external environment, etc.
继发性肌张力障碍，可以由脑部肿瘤、感染或者外界环境的特殊刺激等造成。
2
Objective to analyze the long term effect of botulinum toxin a (Btx-A) in cervical dystonia and to discuss the incidence and mechanisms of secondary non-responsiveness.