Trunk Angular Kinematics During Slip-Induced Backward Falls and Activities of Daily Living

Abstract

Prior to developing any specific fall detection algorithm, it is critical to distinguish the unique motion features associated with fall accidents. The current study aimed to investigate the upper trunk angular kinematics during slip-induced backward falls and activities of daily living (ADLs). Ten healthy older adults (age ¼ 75 6 6 yr (mean 6 SD)) were involved in a laboratory study. Sagittal trunk angular kinematics were measured using optical motion analysis system during normal walking, slip-induced backward falls, lying down, bending over, and various types of sitting down (SN). Trunk angular phase-plane plots were generated to reveal the motion features of falls. It was found that backward falls were characterized by a simultaneous occurrence of a slight trunk extension and an extremely high trunk extension velocity (peak average ¼ 139.7 deg/s), as compared to ADLs (peak average ¼ 84.1 deg/s). It was concluded that the trunk extension angular kinematics of falls were clearly distinguishable from those of ADLs from the perspective of angular phase-plane plot. Such motion features can be utilized in future studies to develop a new prior-to-impact fall detection algorithm.

Description, reliability and utility of a ground-reaction-force triggered protocol for precise delivery of unilateral trip-like perturbations during gait

“…In response to the larger perturbations, both groups exhibited greater peak trunk flexion angles. Our results aligned with the previous findings that more severe falls is associated with a loss of trunk control [ 37 , 38 ]. The magnitude main effect we found also echoed with the results by Lee et al who examined the slip recovery responses after different severities of perturbation [ 39 ].…”

Accuracy of Kinovea software in estimating body segment movements during falls captured on standard video: Effects of fall direction, camera perspective and video calibration technique

“…For these applications, the small error of Kinovea in measuring peak vertical velocity over a wide range of conditions should allow the user to detect small differences between conditions (if they exist). In contrast, if the user instead wishes to compare the time-varying angular velocities of body segments [ 48 ], for which Kinovea had a substantially higher measurement error, the (actual) difference between conditions may need to be quite large, to overcome the inherent errors and be detected from Kinovea-based analysis. Supplementary S1 Table allows readers to identify the expected level of accuracy for specific combinations of kinematic outcome, body part, fall direction, and approach for video collection and calibration.…”

Large gaze shift generation while standing: the role of the vestibular system

“…We found vestibular information to be important not only for the timely termination of gaze saccades but also for shaping online head-in-space and trunk movement, as suggested by the significantly higher jerk cost values in patients, resulting in higher signal-dependent noise (Todorov 2004). The increased trunk sway path after turning implies poor control of trunk movements, the heaviest segment in the body, imposing the risk of losing balance with catastrophic consequences (Liu and Lockhart 2014; Paquette et al 2016; Schniepp et al 2017). As such, it should perhaps be unsurprising that trunk movements are also under vestibular control (Day and Reynolds 2005).…”