Femoral neck strain prediction during level walking using a combined musculoskeletal and finite element model approach
Coupled musculoskeletal-finite element modelling approaches have emerged in recent years as a novel way to investigate femoral neck loading during various daily activities. Combining personalised gait data with finite element models will not only allow us to study changes in motion/movement, but also their effects on critical internal structures, such as the femur.
This study from our MultiSim researchers, for the first time, proposed a pipeline for a fully personalised multiscale (body-organ level) model to investigate the strain levels at the femoral neck during a normal gait walking cycle. Muscle forces derived from the body level musculoskeletal models were used as boundary constraints on the finite element femur models.
The results suggested that personal variation among individuals is substantial in terms of the amount of loads induced in the femoral neck during normal walking. However, the highest femoral neck loads occur at the toe-off and/or heel strike phases of the gait cycle. The model can be extended to be used for various applications, such as orthopaedics, where this modelling approach could help planning treatment for hip and knee replacement.
Measuring 129Xe transfer across the blood‐brain barrier using MR spectroscopy
In this study, Madhwesha Rao and colleagues from the Polaris research group at the University of Sheffield’s Department for Infection, Immunity & Cardiovascular Disease developed a tracer kinetic model for time‐resolved NMR spectra of HP 129Xe in the human brain to estimate the transfer rate of HP 129Xe from cerebral blood to gray matter that depends on a tracer transfer constant for a known mean transit time and cerebral blood volume for gray matter.
They believe this model will enable further studies to determine regional 129Xe tracer transfer constants with a focus of gaining insight into the pathophysiology of the blood brain barrier.
In addition, in light of the passive nature of the xenon tracer, it could serve as a cross‐reference for studies involving oxygen, water or glucose uptake, which are driven by metabolism and/or electrolytic balance.
Operator-Dependent Variability of Angiography-Derived Fractional Flow Reserve and the Implications for Treatment
Researchers at the University of Sheffield’s Department for Infection, Immunity & Cardiovascular Disease have published a paper in the European Heart Journal – Digital Health which shows that vFFR results are influenced by operator experience of vFFR processing. This had implications for treatment allocation. These results highlight the importance of training and quality assurance to ensure reliable, repeatable vFFR results.