Abstract Archive

Free Achilles tendon external twist can be quantified using high resolution MRI and freehand 3D ultrasound methods. Internal fascicle twist may be measured by using feature tracking methods.

The stretch-shortening cycle is a naturally occurring muscle-tendon function that serves to potently enhance performance, and when implemented until exhaustion results in neuromuscular fatigue that differs from that induced solely by isolated contractions. Comparable with previous reports with soleu...

A deep neural network is used to segment whole slide images of plantar soft tissue sections. Morphology characteristics are computed and compared in aggregate and between diabetic and non-diabetic tissue, yielding trends in the deep adipose layer septal chambers.

Lower-limb joint negative mechanical powers during stand-to-sit movements were computed via inverse dynamics modelling to estimate the biomechanical energy available for regeneration with lower-limb prostheses and exoskeletons. Nine subjects performed 20 standing and sitting movements. Lower-limb ki...

The purpose of this investigation was to determine whether parameters which describe the rate of collagen fibre damage accumulation in a collagen distribution model are dependent on the strain-rate. Fifty rat tail tendons were subjected to one of five different strain rates until failure. Using a co...

154 people with chronic low back pain (CLBP) were randomized to 6 weeks of motor skill training (MST) or strength and flexibility (SF) exercise. At baseline, post-treatment and 6-month follow-up participants completed the modified Oswestry Disability Questionnaire (MODQ), the Numeric Pain Rating Sca...

Robotic elbow flexion training using a newly developed upper limb single-joint Hybrid Assistive Limb (upper limb HAL-SJ) was implemented for patients with elbow flexor reconstruction after brachial plexus injury (BPI). No serious adverse events were observed during upper limb HAL-SJ training in all ...

Little is known about the influence of muscle length on force-enhancement during (FE) and following (rFE) lengthening contractions. Preliminary data shows that during electrically stimulated contractions, FE and rFE are relatively greater at a longer, compared with a shorter muscle length, which ind...

Allowing the arms to swing naturally while carrying a load yields a similar cost to carrying a load at the waist, which is generally considered to be the most inexpensive load carrying method.

Normalized jerk is an established metric for the assessment of kinematic fluency across a range of human movements (e.g. writing, manual aiming, balance, and gait) [1-3]. While normalized jerk has been employed to evaluate manual disfluencies in Parkinson disease (PD) patients over extended trials, ...

The purpose of this investigation was to quantify the mechanical response of healthy facet capsular ligaments (FCL) in a porcine model. Twenty-five porcine FCL samples were subjected to uniaxial stress-relaxation tests at 30% and 50% strain to quantify their elastic and viscoelastic properties. Resu...

Carpal tunnel syndrome (CTS) is a prevalent peripheral neuropathy due to median nerve compression. Non-neutral wrist posture and repetitive finger movement are proposed workplace risk factors for CTS. This study investigated median nerve blood flow, size, and tendon mechanics with ultrasound in 35 C...

Military personnel demonstrated asymmetrical knee strength and loading during landing from different dynamic tasks. Though increased knee flexion significantly improved shock attenuation, only peak knee flexion on the non-dominant limb during a single leg drop landing correlated to knee extension st...

The purpose of this study is to generate a realistic human knee exoskeleton model based on a physical system, create a human-machine system (HMS) in a musculoskeletal modelling software, and simulate assistive strategies and human-machine interaction based on joint kinematics. A knee exoskeleton was...

We analyzed the motion characteristics of a hemiplegic patient reaching on a desk by comparing them with a healthy subject using three-dimensional (3D) motion analysis and electromyogram (EMG). In the hemiplegic subject, joint movement range, motion speed, and motion trajectory were remarkably infer...

Using a novel decomposition system capable of tracking the firing behaviour of motor units during dynamic tasks, we investigated for the first time the control of motor units during fatiguing dynamic flexion/extension contractions of the quadriceps muscle. We observed increasing motor unit firing ra...

To perform cross validate between Computed Muscle Control (CMC) results from musculoskeletal simulation and existing experimental data, we compared the compensatory activation of other leg muscles with paralyzed gastrocnemius (GCM) medial head. As a result, muscle activities from CMC showed similar ...

It is currently unclear whether shear wave velocity (SWV) is able to predict changes in muscle stiffness independent of changes in stress, as these covary in muscle and SWV is known to depend on both stress and the material properties of a tissue. Our unique animal model allowed us to match ultrasou...

Tendon tissue engineering approaches are challenged by a limited understanding of the role mechanical loading plays in normal tendon development. We propose that the increased loading that developing postnatal tendons experience with the onset of locomotor behavior impacts tendon formation. In this ...

One of the main limitation of CT imaging and especially Dynamic CT acquisitions of the lower limb is the unavailability of devices that create weight-bearing (WB). This study aimed to validate a novel device developed for this proposes. 15 healthy subjects performed a series of orthostatic squats, f...

The foot’s role in walking on sloped surfaces is currently unclear. Here, we used a multi-segment foot model to explore how the foot adapts its mechanical work production to incline and decline walking.

Different adaptation rates have been reported in studies involving ankle exoskeletons designed to reduce the metabolic cost of their wearers. The purpose of this study was to characterize energetic adaptations occurring over multiple training sessions in a novel exosuit assisting the hip joint. The ...

Wearable device adoption is on the horizon for various populations, however there has been little consideration of long-term device impacts on the musculoskeletal system. Using a computational model, we investigated the influence of both exoskeleton device parameters and anticipated user behavioral ...

In human gait, the ankle is commonly modelled as a linear rotational spring that stores and returns energy throughout stance. However, this model ignores the higher-order damping effects of the physiological ankle joint. More accurate characterizations of these nonlinear phenomena may help optimize ...

Slot scanning X-ray systems such as DXA and EOS provide low-dose high-contrast images of internal anatomy. The advantages of these devices are offset by an inherent susceptibility to motion artefact, as images are collected line-by-line. We present a novel method to measure patient motion and correc...

Diabetic foot is a severe complication and represents the most common cause of non-traumatic amputation. The goal of this study was to simulate diabetic foot behaviour and soft tissues internal stresses by taking into account muscle activation, muscle forces, altered foot kinematics and loads. Gait ...

Abrupt deceleration is a common practice in several sports, where sudden changes of direction are needed to perform at the highest level. The aim of this work is to estimate muscle forces and muscle contributions to the acceleration of the center of mass during a rapid anterior/posterior (A/P) decel...

Marker error affects musculoskeletal (MSK) modeling outputs. For effective marker set optimization it is essential to examine the errors of all markers. Data of 11 subjects were collected during a single-leg forward jump-landing (FJ). OpenSim Inverse Kinematics (IK) was performed and maximum (max) e...

When faced with changes in surface stiffness, humans opt to preserve efficient movement dynamics by altering the spring-like mechanics of their legs, maintaining an invariant series stiffness of leg and surface. Here we examined the contribution of the foot to this mechanism.

The versatile soft tissue contrast of magnetic resonance imaging (MRI) has enabled studying local strains in muscle fiber direction (Ef) as probed by diffusion tensor imaging (DTI). Recently, tracked fascicles of medial gastrocnemius (GM) muscle showed heterogeneous Ef distributions. As opposed to a...