Abstract Archive

A procedure is presented by which a non-stationary signal can be partitioned into sections to apply different Butterworth filter cut-off frequencies to respective sections when necessary. The Teager-Kaiser Energy Operator (TKEO) is used to divide the signal into sections based on their energy. The p...

Quadriceps weakness is a common clinical sign following anterior cruciate ligament reconstruction surgery (ACLR). We examined quadriceps strength and limb symmetry index (LSI) from different types of functional tests: isokinetic dynamometry, hop tests, and leg press. A total of 26 subjects with ACLR...

Upright human standing requires stabilization of both translational and rotational degrees-of-freedom in the sagittal plane that is primarily accomplished by coordination of joint torques at the hip, knee, and ankle. Those torques produce the ground-on-foot force (F) which has recently been shown to...

A 6000% increase in the number of finite element papers published between 1980 and 2009 has been reported [1]. However, finite element convergence and error analysis have not been adequately addressed in the literature. In this study, fundamental relations of finite element convergence analysis were...

This research examined age-related changes in muscle strength and multi-channel surface electromyography (EMG) spatial parameters during isometric and isokinetic knee extensions. Peak torque, mean EMG amplitude, intensity, entropy and Coefficient of Variation (CV) were compared across age and sex. W...

Musculoskeletal ultrasound imaging (USI) was used to assess gluteal muscle activity throughout walking gait among healthy individuals, patients with chronic ankle instability (CAI), and lateral ankle sprain “copers”. While gluteus maximus activity was comparable across groups throughout the gait...

Understanding differences in locomotor biomechanics between walking and running provides fundamental information about human ambulation. Recently, studies of ankle mechanical impedance during locomotion have provided new insight into disturbance response, stability, and energy transfer. Despite stud...

This research describes the error involved in a measurement method which uses ultrasound coupled with external motion capture to measure intervertebral motion of the lumbar spine in the sagittal plane. The findings suggest the method is both robust and repeatable, warranting further investigation in...

Professional basketball players experience a high rate of game-related injuries and a large number of non-contact injuries have been documented. Neuromuscular risk factors have provided strong theoretical support to clinical observations, in relation to non-contact Anterior Cruciate Ligament (ACL) i...

The purpose of this study was to compare elderly faller classifications using pressure mat and force parameters as input to machine learning algorithms. Balance and gait were assessed using pressure mat and force plate data in 59 non-fallers (NF) and 41 fallers (F). Biomechanical parameters included...

Most state-of-the-art prosthetic controllers define modes of operation corresponding to terrain types such as flat-ground walking or stair ascent. This control policy can create impairments for locomotion when unique situations arise, such as in obstacle avoidance or unstructured terrain. Human loco...

A systematic review and meta-analysis were performed to investigate neuromuscular changes after Tai Chi Practice. Healthy old Tai Chi practitioners demonstrated lower muscle latencies and longer muscle activation times during reaching tasks.

This study examines the discrepancy between an assumed neutral-zero position and the actual posture of the lower extremity of young and elderly subjects during the calibration process of an IMU system. The joint angles were calculated using a marker based optical motion capture system. The results s...

We hypothesize that acto-myosin cross-bridge cycling dynamics govern history-dependence in muscle mechanics and muscle spindle afferent feedback that may impact human postural behaviors. Here we combine in vitro, in vivo, and in silico studies to determine movement amplitude thresholds affecting his...

The prevalence of shoulder pathology increases with age, but the progressive changes driving this pathology remain unknown. Identifying the changes preceding symptom onset may permit early detection and prevention of pathology. Altered strength and coordination are thought to contribute to tissue de...

The dynamic behaviour of the foot’s medial longitudinal arch (MLA) during running is an important feature capable of storing and returning energy to the system. The possibility of enhancing this feature through training may lead to changes in performance and injury prevention. We conducted a rando...

An automated approach to predict personalized progression of knee osteoarthritis (OA) was developed and compared against 8-year follow-up data of 104 subjects. The developed approach was based on the subject information, subject-specific anatomical dimensions from MRI and finite element (FE) simulat...

Adults with obesity are at greater risk for knee osteoarthritis (KOA). Greater quadriceps function, but not knee flexion during gait, was associated with a larger medial to lateral femoral cartilage thickness ratio and a lower femoral cartilage echo-intensity. Adverse femoral cartilage outcomes that...

There exists no clear guidance for the biomechanical accommodation period to a prosthetic device for persons with lower limb loss. As such, studies have utilized accommodation periods ranging from 5 minutes to >1 year before commencing data collection [1], potentially limiting reliability and validi...

The pathogenesis of osteoarthritis (OA) involves both metabolic and biomechanical factors. However, the mechanistic implications of contributing factors – obesity, adiposity, and metabolic syndrome – have been difficult to determine due to the complexities of their interactions. To gain further ...

This study investigated a method to use inertial measurement units (IMUs) in certain types of baseball biomechanics research. The method calculates the timing of maximum knee height (MKH) and ball release (BR) using gyroscopic data and defines them as the starting and ending points of the pitching m...

The margin of stability (MoS) is often quantified relative to an intended walking direction. This approach may not be suitable when the intended direction is altered, variable, or unknown. The purpose of this study was to describe and validate the approach of calculating the lateral minimum MoS rela...

Magneto-Inertial technology is an established alternative to optical motion capture for studying human movement. However, accuracy of its orientation estimation is still an open issue. In this study, we performed a concurrent validation of four common sensor fusion algorithms at three different spee...

The intrinsic foot muscles are known to contribute to postural control during upright stance and locomotion. However we know little about the role of these muscles in stabilization following unexpected perturbations. We conducted an experiment in which subjects were trained to repeatedly step at a p...

The purpose of this study was to compare the changes in gait spatio-temporal variables during metronome walking in healthy young adults and elderly groups. In the metronomic walking, the mean and variability of stride time were decreased in young adults group, but the mean of stride length and strid...

Rearfoot (RF) and non-rearfoot strike walking (NRFSW) data from a homogenous population were collected to analyze distal foot joints kinematics. With a multi-segment foot model, kinematic differences were found at the ankle and midtarsal (MT) joint during the two walking conditions. The results may ...

One-handed lifts, frequently used for lifting of light objects or activities of daily living (ADL), are understudied in the biomechanics literature. Twenty healthy participants (30-70 years old) matched in age and sex to 18 participants with low back pain (LBP) were recruited to compare a one-handed...

The purpose of this ongoing study is to assess back extension endurance time and muscle fatigue of university students with and without history of low back pain (LBP). To date, 11 graduate students (5 with and 6 without LBP) have participated, and the final sample will be 30 (15/group). The electrom...

A methodology is outlined for conducting a subject-specific analysis for a low speed rear-end collision. To demonstrate, a MADYMO model was built from 3D laser scan data of the subject driver and vehicle interior, then given motion consistent with imaging of the subject vehicle’s Event Data Record...