Abstract Archive

Animal lower limb muscle-tendon units (MTUs) typically have intramuscular and extramuscular tendons, which are known as aponeuroses and tendons, respectively. Due to their similar passive material properties, both aponeuroses and tendons are often grouped into a single series elastic element that is...

Unicompartmental knee arthroplasty (UKA) replaces the damaged compartment of the osteoarthritic knee with less tissue damage and presumably better restoration of the kinematics compared to total knee arthroplasty (TKA). However, the outcome depends heavily on the accurate restoration of the mechanic...

Recordings of in vivo function in two rat distal hindlimb muscles were obtained across gait and grade conditions to analyse how force, fascicle strain and work are modulated in relation to changes in locomotor requirements. In vivo measurements are then used to evaluate Hill-type muscle models based...

The implant-to-bone interface of endoprostheses is a critical region affecting the stability of the implant. Current advancements in additive manufacturing allow to manufacture novel bone-replicating porous surfaces capable to enhance osteointegration. In this study, small cylindrical porous samples...

The aponeurosis of human muscles represents a significant proportion of the elastic tissues in series with the muscle. However, the aponeurosis should not be considered a simple spring, as is often assumpted in biomechanical models (e.g. Hill-type muscle models). Recent evidence for the effects of f...

Abnormal mechanical loading can initiate and progress degenerative joint disease. In order to predict these processes, failure thresholds for the tissues involved, including cartilage, are needed. This study used a combined experimental and computational framework to identify microscale first princi...

The kinematic characteristics and the passive mechanical properties of the ankle joint are determined primarily by the morphology of the articulating surfaces. Designing artificial surfaces for Total Ankle Replacement (TAR) that can effectively replace natural surfaces damaged by arthritis requires ...

This paper deals with the design of a wearable multi-sensor system (INDIP) that exploits a synergistic integration of different sensor types to provide a “best available” solution for digital gait assessment in real world scenarios. The system includes in its full bilateral configuration 2 Magne...

Human-in-the-loop optimization is a powerful strategy for customizing exoskeleton assistance for an individual, but optimization of many control parameters becomes resource-intensive. We used simulations to determine if coupling assistance between lower-limb degrees-of-freedom (DOFs) could produce l...

Achilles tendinopathy is a well-known pathology that can vary in both chronicity and symptom presentation. Pain, although often being used as an indicator of the severity of the pathology, is not always present and symptoms fluctuate throughout the stages of pathology. Advanced tendinosis accompanie...

The present study tested the hypothesis that increasing Achilles tendon stiffness by means of resistance exercise training will increase the effectiveness of calf stretching exercises for increasing gastrocnemius muscle fascicle length in children with CP. Measurements were taken in an intervention ...

In vivo large animal experiments are essential where the biological response is imperative to the research question. Such studies may be used to answer fundamental questions about the spine and spinal cord in healthy, diseased and injured states, or for the pre-clinical evaluation of procedures and ...

The functional design of skeletal muscle is shaped by conflicting selective pressures between support and propulsion.This study uses a custom-built OpenSim model of varanid lizards to understand how size-related changes are reflected in changes in joint moments at the knee and ankle.

Our musculoskeletal system contains several muscle groups in which different muscles share a tendon. Most well-known are the quadriceps muscles, sharing the patellar tendon, and the triceps surae muscles, sharing the Achilles tendon (AT). The structure and mechanical properties of these tendons have...

Jean Landa Pytel was one of the founders of the American Society of Biomechanics (ASB), one of the first women in the biomechanics PhD program at the Pennsylvania State University and a mentor to many women in ASB. With her passing last year, it is timely to highlight the importance of mentoring (pe...

Soft-tissue vibrations generate discomfort and thus require a greater muscle contribution to preserve an efficient motion. Besides, this may lead to an earlier onset of muscle fatigue. As a matter of fact, reducing tissue vibrations is of great interest from a comfort and performance standpoint. Thi...

Dr. Ahmed studies the costs and rewards underlying the control of movement using a neuroeconomic approach. She will discuss her foundational work investigating the role of energetic cost in shaping non-locomotor tasks, including arm reaching and eye movements.

Dynamic elastography imaging, whether based on Magnetic Resonance or Ultrasound modalities, attempts to reconstruct quantitative maps of the viscoelastic properties of biological tissue, properties that are altered by disease and injury. Reconstruction often assumes isotropy and homogeneity and negl...

Skeletal muscles normally take the form of muscle-tendon unit (MTU) where muscle fibers act as activation-driven actuators while tendinous tissues act as viscoelastic springs.The interaction of the two components can be optimized for enhancing motor performance in a mechanically efficient manner, an...

Neuromuscular electrical stimulation (NMES) is generally delivered to superficial skeletal muscles in static conditions (without functional movement occurring) and at sufficiently high current intensities to evoke visible contractions, with the goals to substitute/complement voluntary exercise (clin...

After total joint replacement, patients aim to resume typical activities of daily living but also to perform sportive and athletic activities. However, there is only little knowledge about the in vivo joint loads acting during such activities. Furthermore the group of patients receiving an artificia...

We analysed the sagittal plane stance phase joint mechanics of athletes with and without unilateral below the knee amputation (BKA) during maximum speed sprinting and long jump. We estimated the strut, spring, motor and damper like function of the main lower extremity joints using functional joint i...

Most running studies are conducted in laboratories and lack ecologic validity. Purpose 1. compare landing impacts between footstrike patterns (FSPs) during a marathon and 2. assess the relationship between speed and landing impacts across FSPs. Methods: Tibial shock of 226 M+F individuals (44.3±1...

Exercise when young has been shown to induce an adaptive response that may be beneficial for lifelong bone health. Using gait experiments coupled with finite element models, we sought to understand how bone accommodates the mechanical demands associated with increasing mass. We found that both murin...

For understanding intervertebral disc (IVD) degeneration associated back pain and for the development of suitable treatment strategies, it is important to know how mechanical influences regulate cellular responses and their impact on disc physiology and pathology. Understanding of IVD mechano-biolog...

This study investigated the minimum sensor configuration (individual or pair) to achieve the simplest cost-effective sensor fusion configuration for robust gait event detection. Five sensors were attached to a powered ankle-foot orthosis: foot IMU, shank IMU, ankle potentiometer, heel contact sensor...

Mechanical loading plays an important role in maintaining normal cartilage health. On the other hand, abnormal mechanical loading potentially results in cartilage degeneration. However, there is limited data quantifying the in vivo cartilage mechanical strain response during activities of daily livi...

Each skeletal muscle commonly comprises a muscle-tendon unit (MTU) where muscle fibers act as actuators while tendinous tissues act as elastic springs.Recent findings however point to the need to view skeletal muscles as the unity of multiple MTUs interacting with each other. Some in vivo findings i...

The adjustments in motor unit recruitment and rate coding and the modulation of a spinal reflex pathway appear to differ when a lengthening contraction is performed on an isokinetic dynamometer compared with the lowering of an inertial load.

The dynamics of the plantarflexor muscles introduce a considerable delay in the postural control system of standing, destabilizing standing balance. Such dynamics had to be considered when developing a closed-loop controller for standing balance using functional electrical stimulation (FES). This pr...