Effect of test duration and sensor location on the reliability of standing balance parameters derived using body-mounted accelerometers.

Background: Balance parameters derived from wearable sensor measurements during postural sway have been shown to be sensitive to experimental variables such as test duration, sensor number, and sensor location that influence the magnitude and frequency-related properties of measured center-of-mass (COM) and center-of-pressure (COP) excursions. In this study, we investigated the effects of test duration, the number of sensors, and sensor location on the reliability of standing balance parameters derived using body-mounted accelerometers.

Methods: Twelve volunteers without any prior history of balance disorders were enrolled in the study.

Clinical Static Balance Assessment: A Narrative Review of Traditional and IMU-Based Posturography in Older Adults and Individuals with Incomplete Spinal Cord Injury.

Maintaining a stable upright posture is essential for performing activities of daily living, and impaired standing balance may impact an individual's quality of life. Therefore, accurate and sensitive methods for assessing static balance are crucial for identifying balance impairments, understanding the underlying mechanisms of the balance deficiencies, and developing targeted interventions to improve standing balance and prevent falls. This review paper first explores the methods to quantify standing balance.

Nonlinear neural control using feedback linearization explains task goals of central nervous system for trunk stability in sitting posture.

Characterizing the task goals of the neural control system for achieving seated stability has been a fundamental challenge in human motor control research. This study aimed to experimentally identify the task goals of the neural control system for seated stability.Ten able-bodied young individuals participated in our experiments, which allowed us to measure their body motion and muscle activity during perturbed sitting.

Nonlinear response of human trunk musculature explains neuromuscular stabilization mechanisms in sitting posture.

. Determining the roles of underlying mechanisms involved in stabilizing the human trunk during sitting is a fundamental challenge in human motor control. However, distinguishing their roles requires understanding their complex interrelations and describing them with physiologically meaningful neuromechanical parameters.

Instrumented Functional Test for Objective Outcome Evaluation of Balance Rehabilitation in Elderly Fallers: A Clinical Study.

Introduction: Observational tests, e.g., the Berg Balance Scale (BBS) are widely used for balance evaluation in the elderly fallers.

Predicted Threshold for Seated Stability: Estimation of Margin of Stability Using Wearable Inertial Sensors.

Individuals with spinal cord injury suffer from seated instability due to impaired trunk neuromuscular function. Monitoring seated stability toward the development of closed-loop controlled neuroprosthetic technologies could be beneficial for restoring trunk stability during sitting in affected individuals. However, there is a lack of (1) a biomechanical characterization to quantify the relationship between the trunk kinematics and sitting balance; and (2) a validated wearable biomedical device for assessing dynamic sitting posture and fall-risk in real-time.

Postural control strategy after incomplete spinal cord injury: effect of sensory inputs on trunk-leg movement coordination.

Background: Postural control is affected after incomplete spinal cord injury (iSCI) due to sensory and motor impairments. Any alteration in the availability of sensory information can challenge postural stability in this population and may lead to a variety of adaptive movement coordination patterns. Hence, identifying the underlying impairments and changes to movement coordination patterns is necessary for effective rehabilitation post-iSCI.

Using wearable sensors to characterize gait after spinal cord injury: evaluation of test-retest reliability and construct validity.

Study Design: Quantitative cross-sectional study.

Objectives: Evaluate the test-retest reliability and the construct validity of inertial measurement units (IMU) to characterize spatiotemporal gait parameters in individuals with SCI.

Setting: Two SCI rehabilitation centers in Canada.

Validity of using wearable inertial sensors for assessing the dynamics of standing balance.

Observational balance tests (e.g., Berg Balance Scale) are used to evaluate fall-risk.

Sensor-to-body calibration procedure for clinical motion analysis of lower limb using magnetic and inertial measurement units.

Magnetic and Inertial measurement units (MIMUs) have become exceedingly popular for ambulatory human motion analysis during the past two decades. However, measuring anatomically meaningful segment and joint kinematics requires virtual alignment of the MIMU frame with the anatomical frame of its corresponding segment. Therefore, this paper presents a simple calibration procedure, based on MIMU readouts, to align the inertial frame of the MIMU with the anatomical frames, as recommended by ISB.

Optimal Estimation of Anthropometric Parameters for Quantifying Multisegment Trunk Kinetics.

Kinetics assessment of the human head-arms-trunk (HAT) complex via a multisegment model is a useful tool for objective clinical evaluation of several pathological conditions. Inaccuracies in body segment parameters (BSPs) are a major source of uncertainty in the estimation of the joint moments associated with the multisegment HAT. Given the large intersubject variability, there is currently no comprehensive database for the estimation of BSPs for the HAT.

Quantification of multi-segment trunk kinetics during multi-directional trunk bending.

Background: Motion assessment of the body's head-arms-trunk (HAT) using linked-segment models, along with an inverse dynamics approach, can enable in vivo estimations of inter-vertebral moments. However, this mathematical approach is prone to experimental errors because of inaccuracies in (i) kinematic measurements associated with soft tissue artifacts and (ii) estimating individual-specific body segment parameters (BSPs). The inaccuracy of the BSPs is particularly challenging for the multi-segment HAT due to high inter-participant variability in the HAT's BSPs and no study currently exists that can provide a less erroneous estimation of the joint moments along the spinal column.