The surface electromyography characteristics of essential tremor, Parkinson′s disease and essential tremor-Parkinson′s disease syndrome
10.3760/cma.j.cn113694-20240723-00506
- VernacularTitle:原发性震颤、帕金森病、原发性震颤-帕金森病综合征的表面肌电特点
- Author:
Huanhuan FENG
1
;
Zhongxi LIN
;
Ping ZHUANG
;
Yongtao ZHOU
;
Wei ZHANG
;
Erhe XU
;
Chan PIU
Author Information
1. 首都医科大学宣武医院神经内科 北京市老年病医疗研究中心,北京100053
- Publication Type:Journal Article
- Keywords:
Essential tremor;
Parkinson disease;
Essential tremor-Parkinson′s disease syndrome;
Electromyography
- From:
Chinese Journal of Neurology
2025;58(3):254-260
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To compare the surface electromyography characteristics of essential tremor (ET), Parkinson′s disease (PD) and essential tremor-Parkinson′s disease syndrome (ET-PD).Methods:A total of 74 patients [ET group ( n=23), PD group ( n=30), and ET-PD group ( n=21)] admitted to the Parkinson′s and Movement Disorders Center of the Department of Neurology of Xuanwu Hospital from August 2020 to December 2023 were enrolled, and results of their bilateral upper limbs surface electromyography (sEMG) were collected. sEMG activities were analyzed offline. Power spectral analysis was performed to explore the sEMG activities. One-way analysis of variance and chi-square test were used to compare the differences of electrophysiological parameters. Results:For the ET group characterized by postural tremor, the frequency was (6.06±0.68) Hz, the amplitude was (1 200.91±360.69) μV, the proportion of alternating contractions was 30.4% (7/23), and the proportion of harmonic resonances was 34.8% (8/23). For the PD group characterized by rest tremor, the frequency was (4.81±0.61) Hz, the amplitude was (1 057.40±354.52) μV, the proportion of alternating contractions was 73.3% (22/30), and the proportion of harmonic resonances was 70.0% (21/30). For the ET-PD group in rest and postural state respectively, the frequencies were (5.04±0.44) Hz and (5.80±0.47) Hz, the amplitudes were (1 026.05±191.90) μV and (1 196.67±212.12) μV, the proportions of alternating contractions were 52.4% (11/21) and 38.1% (8/21), and the proportions of harmonic resonances were 52.4% (11/21) and 33.3% (7/21). Analysis of variance revealed that tremor frequencies for the PD group and the ET-PD group in rest state were lower than the ET group and the ET-PD group in postural state ( F=27.439, P<0.001). The proportion of alternating contractions for the PD group was higher than the ET group ( χ 2=9.669, P=0.002) and the ET-PD group in postural state ( χ 2=6.333, P=0.012). The proportion of harmonic resonances for the PD group was higher than the ET group ( χ 2=6.517, P=0.011) and the ET-PD group in postural state ( χ 2=6.708, P=0.010). No statistically significant differences were found for tremor amplitudes among all the groups ( F=2.143, P=0.100). Conclusions:ET is characterized by postural tremors, with a higher frequency and a lower alternating contractions and harmonic resonances. PD is characterized by rest tremors, with a lower frequency and a higher alternating contractions and harmonic resonances. The parameters of ET-PD are between ET and PD, which provide objective evidences for differential diagnosis of tremors.