Validation of plantar pressure simulations using finite and discrete element modelling in healthy and diabetic subjects

Abstract

A B S T R A C TThe response to stance perturbations changes with age. The shift from an ankle to a hip strategy with increasing perturbation magnitude occurs at lower accelerations in older than in young adults. This strategy shift has been related to age-related changes in muscle and sensory function. However, the effect of isolated changes in muscle or sensory function on the responses following stance perturbations cannot be determined experimentally since changes in muscle and sensory function occur simultaneously. Therefore, we used predictive simulations to estimate the effect of isolated changes in (rates of change in) maximal joint torques, functional base of support, and sensory noise on the response to backward platform translations. To evaluate whether these modeled changes in muscle and sensory function could explain the observed changes in strategy; simulated postural responses with a torque-driven double inverted pendulum model controlled using optimal state feedback were compared to measured postural responses in ten healthy young and ten healthy older adults. The experimentally observed peak hip angle during the response was significantly larger (5°) and the functional base of support was smaller (0.04 m) in the older than in the young adults but peak joint torques and rates of joint torque were similar during the recovery. The addition of noise to the sensed states in the predictive simulations could explain the observed increase in peak hip angle in the elderly, whereas changes in muscle function could not. Hence, our results suggest that strength training alone might be insufficient to improve postural control in elderly.

In Silico-Enhanced Treatment and Rehabilitation Planning for Patients with Musculoskeletal Disorders: Can Musculoskeletal Modelling and Dynamic Simulations Really Impact Current Clinical Practice?

“…Similar design optimisation (i.e., arch size, location, and manufacturing material) can be applied to shoe insoles to study the effect of variables such as joint contact forces and plantar pressures [89][90][91][92][93] and, more recently, in the optimised design of insoles [94]. This approach is highly relevant in the area of diabetic foot care, where individual insole design is key in preventing foot ulcer formation [89,95]. Further, MSK modelling and simulations can be used in the optimisation of assistive devices (Figure 6) and exoskeletons.…”

“…With respect to exoskeletons, the use of predictive simulations can be used to optimise control strategy (e.g., for balance control or evaluation of comfort based on contact pressure evaluation [100,101]). [89,95]. Further, MSK modelling and simulations can be used in the optimisation of assistive devices (Figure 6) and exoskeletons.…”

Relationship between Plantar Pressure and Sensory Disturbance in Patients with Hansen’s Disease—Preliminary Research and Review of the Literature

“…In particular, researchers have established an accurate method utilizing musculoskeletal foot modeling and finite element 3D subject-specific modeling to predict ulcer risk in the field of diabetes. The application of this newly developed method will open further prospects for the treatment of Hansen's disease [68,69].…”