Title :
Quantitative Description of the Lie-to-Sit-to-Stand-to-Walk Transfer by a Single Body-Fixed Sensor
Author :
Bagala, Fabio ; Klenk, Jochen ; Cappello, Angelo ; Chiari, Lorenzo ; Becker, C. ; Lindemann, U.
Author_Institution :
Dept. of Electr., Electron. & Inf. Eng.-Guglielmo Marconi, Univ. of Bologna, Bologna, Italy
Abstract :
Sufficient capacity and quality of performance of complex movement patterns during daily activity, such as standing up from a bed, is a prerequisite for independent living and also may be an indicator of fall risk. Until now, the transfer from lying-to-sit-to-stand-to-walk (LSSW) was investigated by functional testing, subjective rating or for activity classification of subtasks. The aim of this study was to use a single body-fixed inertial sensor to describe the complex movement of the LSSW transfer. Fifteen older patients of a geriatric rehabilitation clinic (median age 81 years) and ten young, healthy persons (median age 37 years) were instructed to stand up from bed in a continuous movement and to start walking. Data acquisition was performed using an inertial measurement unit worn on the lower back. Parameters extracted from the sensor outputs were able to correctly classify the subjects into a correct group with sensitivity and specificity between 90% and 100%. ICCs of the descriptive parameters ranged between 0.85 and 0.95 in the cohort of older patients. The different strategies adopted to transfer from lying to standing up were estimated through an extended Kalman filter. The results obtained in this study suggest the usability of the instrumented LSSW test in clinical settings.
Keywords :
Kalman filters; biomedical measurement; data acquisition; feature extraction; gait analysis; geriatrics; inertial systems; patient rehabilitation; sensors; LSSW; activity classification; complex movement patterns; data acquisition; extended Kalman filter; geriatric rehabilitation clinic; lie-to-sit-to-stand-to-walk transfer; parameter extraction; single body-fixed sensor; Acceleration; Accelerometers; Gyroscopes; Noise; Silicon; Testing; Vectors; Bed transfer; discriminant ability; extended Kalman filter (EKF); inertial sensor; reliability; Acceleration; Activities of Daily Living; Adult; Aged; Aged, 80 and over; Aging; Algorithms; Anthropometry; Biomechanical Phenomena; Biosensing Techniques; Cohort Studies; Data Interpretation, Statistical; Electrodes; Equipment Design; Female; Gait Disorders, Neurologic; Humans; Male; Middle Aged; Movement; Posture; Reproducibility of Results; Rotation; Treatment Outcome; Walking;
Journal_Title :
Neural Systems and Rehabilitation Engineering, IEEE Transactions on
DOI :
10.1109/TNSRE.2012.2230189