Pacchetti C, Albani G, Martignoni E, Godi L, Alfonsi E, Nappi G
Parkinson's Disease Centre, IRCSS C. Mondino, University of Pavia, Italy.
Mov Disord. 1995 May;10(3):333-6. doi: 10.1002/mds.870100317.
The "off" painful dystonia (OPD), usually concerning the feet, is a type of abnormal involuntary movement, induced by the chronic use of levodopa. It is mostly observed in the advanced stage of Parkinson's disease (PD), particularly in the early morning, in the evening, and late at night. Indeed, some patients have experienced OPD also during "on" periods when dystonic posture of the foot alternates with dyskinesia. The pain probably is due to sustained muscle contraction, which causes prolonged muscle spasm, as in primary dystonia or torticollis. Dopaminergic drugs like bromocriptine, pergolide, and especially apomorphine (s.c. infusions, or bolus), can dramatically improve the OPD. Anticholinergics baclofen and lithium are alos used in the management of OPD with some benefit. On the other hand, clinical experience shows that in many cases, these therapeutic procedures are not always enough to produce the expected results. Thirty PD patients (22 men and eight women) with OPD of the foot were treated with botulinum toxin (Botox, Btx) using electromyograms to guide injections. Dystonia was evaluated using a quantitative rating scale. The selection of the muscles for Btx treatment was carried out on the basis of foot posture. We injected Btx into tibialis posterior, tibialis anterior, gastrocnemius, flexor digitorum longus, and extensores hallucis longus with a median dose 40 IU for each muscle, distributed in two sites. In all patients, the pain improved within 10 days, whereas in 21 patients, the pain disappeared completely for 4 months (range, 3-7 months); a concomitant improvement in intensity of the dystonic spasm was also observed. No side effects were reported. Seven patients with associated "on" foot dystonia described an improvement of foot posture on walking. In conclusion, in this uncontrolled study, the use of Btx in OPD seemed a promising tool to improve pain linked to foot dystonia; however, because of the well-known underlying dopaminergic defect in OPD, the Btx therapy should be considered only if the dopaminergic treatment established for the management of OPD has failed.
“关期”疼痛性肌张力障碍（OPD）通常累及足部，是一种由长期使用左旋多巴诱发的异常不自主运动。它多见于帕金森病（PD）晚期，尤其是在清晨、傍晚和深夜。实际上，一些患者在“开期”也会出现OPD，此时足部的肌张力障碍姿势与运动障碍交替出现。疼痛可能是由于肌肉持续收缩导致肌肉长时间痉挛引起的，就像原发性肌张力障碍或斜颈那样。多巴胺能药物如溴隐亭、培高利特，尤其是阿扑吗啡（皮下注射或推注），可显著改善OPD。抗胆碱能药物巴氯芬和锂盐在OPD的治疗中也有一定益处。另一方面，临床经验表明，在许多情况下，这些治疗方法并不总能产生预期效果。30例患有足部OPD的PD患者（22例男性和8例女性）接受了肉毒毒素（保妥适，Btx）治疗，注射时使用肌电图进行引导。肌张力障碍采用定量评分量表进行评估。根据足部姿势选择Btx治疗的肌肉。我们将Btx注射到胫后肌、胫前肌、腓肠肌、趾长屈肌和拇长伸肌，每块肌肉的中位剂量为40 IU，分两个部位注射。所有患者的疼痛在10天内均有改善，21例患者的疼痛完全消失达4个月（范围为3 - 7个月）；同时肌张力障碍性痉挛的强度也有所改善。未报告有副作用。7例伴有“开期”足部肌张力障碍的患者称行走时足部姿势有所改善。总之，在这项非对照研究中，Btx用于OPD似乎是改善与足部肌张力障碍相关疼痛的一种有前景的工具；然而，由于OPD中存在众所周知的潜在多巴胺能缺陷，仅当用于OPD治疗的多巴胺能治疗失败时，才应考虑Btx治疗。
