三种机器学习算法用于步态障碍中肌电图模式自动分类的评估
Evaluation of Three Machine Learning Algorithms for the Automatic Classification of EMG Patterns in Gait Disorders.
作者信息
Fricke Christopher, Alizadeh Jalal, Zakhary Nahrin, Woost Timo B, Bogdan Martin, Classen Joseph
机构信息
Department of Neurology, University Hospital of Leipzig, Leipzig, Germany.
Faculty of Mathematics and Computer Science, Leipzig University, Leipzig, Germany.
出版信息
Front Neurol. 2021 May 21;12:666458. doi: 10.3389/fneur.2021.666458. eCollection 2021.
Gait disorders are common in neurodegenerative diseases and distinguishing between seemingly similar kinematic patterns associated with different pathological entities is a challenge even for the experienced clinician. Ultimately, muscle activity underlies the generation of kinematic patterns. Therefore, one possible way to address this problem may be to differentiate gait disorders by analyzing intrinsic features of muscle activations patterns. Here, we examined whether it is possible to differentiate electromyography (EMG) gait patterns of healthy subjects and patients with different gait disorders using machine learning techniques. Nineteen healthy volunteers (9 male, 10 female, age 28.2 ± 6.2 years) and 18 patients with gait disorders (10 male, 8 female, age 66.2 ± 14.7 years) resulting from different neurological diseases walked down a hallway 10 times at a convenient pace while their muscle activity was recorded via surface EMG electrodes attached to 5 muscles of each leg (10 channels in total). Gait disorders were classified as predominantly hypokinetic ( = 12) or ataxic ( = 6) gait by two experienced raters based on video recordings. Three different classification methods (Convolutional Neural Network-CNN, Support Vector Machine-SVM, K-Nearest Neighbors-KNN) were used to automatically classify EMG patterns according to the underlying gait disorder and differentiate patients and healthy participants. Using a leave-one-out approach for training and evaluating the classifiers, the automatic classification of normal and abnormal EMG patterns during gait (2 classes: "healthy" and "patient") was possible with a high degree of accuracy using CNN (accuracy 91.9%), but not SVM (accuracy 67.6%) or KNN (accuracy 48.7%). For classification of hypokinetic vs. ataxic vs. normal gait (3 classes) best results were again obtained for CNN (accuracy 83.8%) while SVM and KNN performed worse (accuracy SVM 51.4%, KNN 32.4%). These results suggest that machine learning methods are useful for distinguishing individuals with gait disorders from healthy controls and may help classification with respect to the underlying disorder even when classifiers are trained on comparably small cohorts. In our study, CNN achieved higher accuracy than SVM and KNN and may constitute a promising method for further investigation.
步态障碍在神经退行性疾病中很常见,即使对于经验丰富的临床医生来说,区分与不同病理实体相关的看似相似的运动模式也是一项挑战。最终,肌肉活动是运动模式产生的基础。因此,解决这个问题的一种可能方法可能是通过分析肌肉激活模式的内在特征来区分步态障碍。在这里,我们研究了使用机器学习技术是否能够区分健康受试者和患有不同步态障碍患者的肌电图(EMG)步态模式。19名健康志愿者(9名男性,10名女性,年龄28.2±6.2岁)和18名因不同神经系统疾病导致步态障碍的患者(10名男性,8名女性,年龄66.2±14.7岁)以方便的步速在走廊上行走10次,同时通过附着在每条腿5块肌肉上的表面肌电图电极记录他们的肌肉活动(总共10个通道)。两名经验丰富的评估人员根据视频记录将步态障碍主要分为运动减少型(n = 12)或共济失调型(n = 6)步态。使用三种不同的分类方法(卷积神经网络-CNN、支持向量机-SVM、K近邻-KNN)根据潜在的步态障碍自动分类肌电图模式,并区分患者和健康参与者。使用留一法训练和评估分类器,使用CNN(准确率91.9%)可以高度准确地对步态期间正常和异常肌电图模式进行自动分类(2类:“健康”和“患者”),但SVM(准确率67.6%)或KNN(准确率48.7%)则不行。对于运动减少型与共济失调型与正常步态的分类(3类),CNN再次获得了最佳结果(准确率83.8%),而SVM和KNN的表现较差(SVM准确率51.4%,KNN准确率32.4%)。这些结果表明,机器学习方法有助于区分患有步态障碍的个体与健康对照,并且即使在相对较小的队列上训练分类器,也可能有助于根据潜在疾病进行分类。在我们的研究中,CNN比SVM和KNN获得了更高的准确率,可能构成一种有前途的进一步研究方法。