Accuracy of a Custom Physical Activity and Knee Angle Measurement Sensor System for Patients with Neuromuscular Disorders and Gait Abnormalities

Sensors

Frank Feldhege²  Anett Mau-Moeller²  Tobias Lindner²  Albert Hein¹  Andreas Markschies³  Uwe Klaus Zettl⁴  Rainer Bader² 

[1] Institute of Computer Science, University of Rostock, Albert-Einstein-Str. 22, Rostock 18059, Germany; E-Mail:;Department of Orthopaedics, University Medicine Rostock, Doberaner Str. 142, 18057 Rostock, Germany; E-Mails:;Medizintechnik Rostock GmbH, Zur Himmelspforte 1, Rostock 18055, Germany; E-Mail:;Department of Neurology, University Medicine Rostock, Gehlsheimer Str. 20, Rostock 18147, Germany; E-Mail:

关键词: physical activity;    accelerometer;    activity assessment;    knee motion;    wearable sensor system;    range of motion measurement;   

DOI  :  10.3390/s150510734

来源: mdpi

【 摘 要 】

Long-term assessment of ambulatory behavior and joint motion are valuable tools for the evaluation of therapy effectiveness in patients with neuromuscular disorders and gait abnormalities. Even though there are several tools available to quantify ambulatory behavior in a home environment, reliable measurement of joint motion is still limited to laboratory tests. The aim of this study was to develop and evaluate a novel inertial sensor system for ambulatory behavior and joint motion measurement in the everyday environment. An algorithm for behavior classification, step detection, and knee angle calculation was developed. The validation protocol consisted of simulated daily activities in a laboratory environment. The tests were performed with ten healthy subjects and eleven patients with multiple sclerosis. Activity classification showed comparable performance to commercially available activPAL sensors. Step detection with our sensor system was more accurate. The calculated flexion-extension angle of the knee joint showed a root mean square error of less than 5° compared with results obtained using an electro-mechanical goniometer. This new system combines ambulatory behavior assessment and knee angle measurement for long-term measurement periods in a home environment. The wearable sensor system demonstrated high validity for behavior classification and knee joint angle measurement in a laboratory setting.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.