Is Low-frequency Repetitive Nerve Stimulation a Reliable Test to Evaluate the Neuromuscular Junction in Myotonic Dystrophy Type 1
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 9
- 试验地点
- 1
- 主要终点
- Reproducibility of rapid decrement at low frequency stimulation.
研究概览
简要总结
The study design is a prospective cohort study. It aims to evaluate the neuromuscular junction in dystrophic myotonia 1 (DM 1) using low-frequency repetitive nerve stimulation (RNS) on several nerve-muscle pairs of the one side including proximal and distal muscles of upper and lower extremities. First, it will be investigated whether a decrement with 3 Hz stimulation, as described in literature, is reproducible in our patient population. If this is the case, it will be examined whether it is the consequence of a dysfunction of the neuromuscular junction or rather linked to a hypo-excitability of some muscle fibers due to myotonia. For this purpose, additional tests including short exercise test (to observe any decrement resulting from an inexcitability in myotonic muscle fibers) and needle EMG (for mapping myotonic discharges in the muscles tested with repetitive nerve stimulation) will be performed. Single fiber-EMG will not be provided in this study as an abnormal result does not necessarily indicate a dysfunction of the neuromuscular junction but could just as well be due to the muscular dystrophy in the context of DM1. Finally, it will be investigated if there is a correlation between the decrement
with 3 Hz stimulation and clinical signs as fixed muscle weakness (via Medical Research Counsil (MRC) scale, DM-activ scale [30]) and fatigue (via MG-ADL scale).
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Single Group
- 主要目的
- Basic Science
- 盲法
- None
入排标准
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •* genetically confirmed DM1
排除标准
- •minor age
- •auto-immune diseases
- •medical conditions involving the neuromuscular junction: (myasthenia gravis, Lambert-Eaton myasthenic syndrome, congenital myasthenia syndromes).
研究组 & 干预措施
Questionnaires
Patients with DM1 were asked to complete a questionnaire to rate a 25-item activity scale (DM1-Activ) and the Myasthenia Gravis Activity of Daily Life scale (MG-ADL) to rate their level of functional burden. For the DM1-Activ a score of 40 alludes no impairment and a score of 0 indicates the highest functional burden of physical activity. This scale has proven to be practical, reliable and valid. For the MG-ADL the total score ranges from 0 to 24, a score of 0 denotes no and 24 the highest functional burden. It should be noted that this scale is not adjusted for DM1. The rationale was to gain information about muscle fatigue and consequently the neuromuscular junction.
干预措施: Low frequency repetitive stimulation (Diagnostic Test)
grip strength via dynamometer
The isometric grip strength was tested by using a dynamometer. The subject will be asked to perform an increasing force against the dynamometer over a period of several seconds.
干预措施: Low frequency repetitive stimulation (Diagnostic Test)
short exercise test
The subject was asked to contract the ADM muscle as hard as possible in isometric conditions for 10 seconds. CMAP's was recorded 2 seconds after the end of the exercise and then every 10 seconds for 50 seconds.
干预措施: Low frequency repetitive stimulation (Diagnostic Test)
needle EMG
The electrical myotonia of each examined muscle was scored according to the Streiss and Sun scale.
干预措施: Low frequency repetitive stimulation (Diagnostic Test)
结局指标
主要结局
Reproducibility of rapid decrement at low frequency stimulation.
时间窗: 1 year
Low stimulation frequency was tested in 6 muscles, to verify the presence of an anomalie of the neuromuscular transmission.
次要结局
- Correlation of decrement with grade of EMG-myotonia(1 year)
- Is there any clinical expression (muscle fatigability) of a possible neuromuscular junction dysfunction(1 year)
研究者
Jella De Ville
medical doctor, principal investigator
Vrije Universiteit Brussel