Cutsforth-Gregory Jeremy K, Hammack Julie E, Matsumoto Joseph Y
Department of Neurology, Mayo Clinic, Rochester, MN, USA.
Parkinsonism Relat Disord. 2017 Aug;41:109-112. doi: 10.1016/j.parkreldis.2017.04.015. Epub 2017 Apr 26.
Orthostatic myoclonus (OM) is a recognized syndrome of gait unsteadiness accompanied by lower limb myoclonus provoked by the assumption of an upright posture. OM typically affects the elderly and is often associated with neurodegenerative disease. We sought to review the clinical and electrophysiologic characteristics of OM due to brain tumor treatment, the first reported lesional cases of this rare disorder.
The database of the Mayo Clinic Rochester Movement Disorders Laboratory was searched for all patients diagnosed with OM from January 2007 to December 2016. All available clinical, radiographic, and surface electromyographic data were reviewed, and patients with a history of primary or metastatic brain tumor were analyzed.
Two patients with OM and brain tumor were identified; both had undergone tumor resection and targeted brain radiation. Both patients complained of unsteadiness while walking and recurrent falls. Tumor pathology (atypical meningioma, gliosarcoma) was centered in the frontal lobe and extended to the supplementary motor area (SMA), pre-SMA, or prefrontal cortex. Medications did not improve gait.
Two cases of brain tumor-related OM suggest that degeneration of frontal motor programming circuits underlies the pathophysiology of OM.
直立性肌阵挛（OM）是一种公认的综合征，表现为步态不稳，并伴有因直立姿势诱发的下肢肌阵挛。OM通常影响老年人，且常与神经退行性疾病相关。我们试图回顾因脑肿瘤治疗导致的OM的临床和电生理特征，这是首次报道的这种罕见疾病的病灶性病例。
检索梅奥诊所罗切斯特运动障碍实验室数据库中2007年1月至2016年12月期间所有诊断为OM的患者。回顾所有可用的临床、影像学和表面肌电图数据，并对有原发性或转移性脑肿瘤病史的患者进行分析。
确定了2例患有OM和脑肿瘤的患者；两人均接受了肿瘤切除和靶向脑放射治疗。两名患者均抱怨行走时不稳和反复跌倒。肿瘤病理（非典型脑膜瘤、胶质肉瘤）集中在额叶，并延伸至辅助运动区（SMA）、前SMA或前额叶皮质。药物治疗未能改善步态。
两例脑肿瘤相关的OM病例表明，额叶运动编程回路的退化是OM病理生理学的基础。
