Validation of a Finite Element Simulation for Predicting Individual Knee Joint Kinematics.

We introduce an in-vivo validated finite element (FE) simulation approach for predicting individual knee joint kinematics. Our vision is to improve clinicians' understanding of the complex individual anatomy and potential pathologies to improve treatment and restore physiological joint kinematics. Our 3D FE modeling approach for individual human knee joints is based on segmentation of anatomical structures extracted from routine static magnetic resonance (MR) images.

Aerosol morphology and particle size distribution in orthopaedic bone machining: a laboratory worst-case contamination simulation. Is high-speed bone machining potentially harmful by pollution and quality schemes and what measures could be taken for prevention?

Aim Of The Study: High-speed bone machining devices with irrigation fluid were used in surgery to spread aerosols and toss tissue particles of varying morphology into the operating room. Based on measurements taken on a phantom object, the shape, size, and spatial contamination distribution of such particles were assessed.

Method: Cadaveric femoral heads were continuously machined with a spherical bur, manually held at a fixed attack angle.

The spatial distribution of aerosols in high-speed bone burring with external irrigation.

It is well-known that the use of high-speed burring devices with irrigation used in bone surgery produces aerosols, and can toss tissue particles into space. The aim of this study was to assess the spatial vertical contamination in the sterile operation field while using a high-speed cutting device at various locations. A fresh porcine knee was resected for 10 min with a high-speed burring device.

Mid- to Long-term Clinical Outcome and Gait Biomechanics After Realignment Surgery in Asymmetric Ankle Osteoarthritis.

Background: Joint-preserving, realignment surgical procedures have gained increasing popularity as treatment of asymmetric early- and mid-stage ankle osteoarthritis. The aim of the present study was to quantify bilateral gait biomechanics in patients who underwent ankle realignment surgery by supramalleolar osteotomies.

Methods: Eight patients, a minimum of 7 years after realignment surgery, and 8 healthy controls were included in this study.

Effects of supramalleolar osteotomies for ankle osteoarthritis on foot kinematics and lower leg muscle activation during walking.

Background: Early stages of asymmetric ankle osteoarthritis can be treated by joint preserving supramalleolar osteotomies that surgically realign the ankle and unload degenerated cartilage. While studies have already shown pain relief and functional improvements, the effects on gait biomechanics are largely unknown. This study investigated patients' gait pattern after supramalleolar osteotomies by focusing on foot kinematics and lower leg muscle activation.

Heel-strike in walking: assessment of potential sources of intra- and inter-subject variability in the activation patterns of muscles stabilizing the knee joint.

The electromyographic (EMG) signal is known to show large intra-subject and inter-subject variability. Adaptation to, and preparation for, the heel-strike event have been hypothesized to be major sources of EMG variability in walking. The aim of this study was to assess these hypotheses using a principal component analysis (PCA).

Automatic selection of a representative trial from multiple measurements using Principle Component Analysis.

Experimental data in human movement science commonly consist of repeated measurements under comparable conditions. One can face the question how to identify a single trial, a set of trials, or erroneous trials from the entire data set. This study presents and evaluates a Selection Method for a Representative Trial (SMaRT) based on the Principal Component Analysis.

Muscle activation of patients suffering from asymmetric ankle osteoarthritis during isometric contractions and level walking - a time-frequency analysis.

Asymmetric osteoarthritis (OA) is a common type of OA in the ankle joint. OA also influences the muscles surrounding a joint, however, little is known about the muscle activation in asymmetric ankle OA. Therefore, the aim of this study was to characterize the patients' muscle activation during isometric ankle torque measurements and level walking.

Gait patterns of asymmetric ankle osteoarthritis patients.

Background: In early stages, ankle osteoarthritis is often asymmetric with only partially degenerated joint surfaces. There is only limited knowledge on the effect of asymmetric ankle osteoarthritis on the patients' gait patterns. Therefore, the aim of this study was to characterize kinematic and kinetic changes compared to healthy adults.

Muscular timing and inter-muscular coordination in healthy females while walking.

The dynamic interplay between muscles surrounding the knee joint, the central nervous system and external factors require a control strategy to generate and stabilise the preferred gait pattern. The electromyographic (EMG) signal is a common measure reflecting the neuromuscular control strategies during dynamic tasks. Neuromuscular control mechanisms, found in processed EMG signals, showed a precise pacing with a pacing rhythm and a tight control of muscle activity in running and maximally contracted muscles.

The effect of sprint and endurance training on electromyogram signal analysis by wavelets.

The purpose of this study was to relate the spectral changes of surface electromyograms (EMGs) to training regimes. The EMGs of M. vastus medialis and M.