# A Novel Wearable Foot and Ankle Monitoring System for the Assessment of Gait Biomechanics
###### Abstract  
Walking is the most basic form of human activity for achieving mobility. As an essential function of the human body, the examination of walking is directed towards the assessment of body mechanics in posture and during movement. This work proposes a wearable smart system for the monitoring and objective evaluation of foot biomechanics during gait. The proposed solution assumes the cross-correlation of the plantar pressure with lower-limb muscular activity, throughout the stance phase of walking. Plantar pressure is acquired with an array of resistive pressure sensors deployed onto a shoe inside along the center of gravity progression line. Lower-limb muscular activity is determined from the electromyogram of the tibialis anterior and gastrocnemius lower limb muscles respectively. Under this scenario, physiological gait assumes the interdependency of plantar pressure on the heel area with activation of the tibialis anterior, as well as plantar pressure on the metatarsal arch/toe area with activation of the gastrocnemius. As such, assessment of gait physiology is performed by comparison of a gait map, formulated based on the footprint-lower-limb muscle cross-correlation results, to a reference gait template. A laboratory proof of concept validates the proposed solution in a test scenario which assumes a normal walking and two pathological walking patterns. EMG; resistive pressure sensor; footprint; center of pressure progression line; microcontroller; smart-shoe; cross-correlation; gait analysis; gait physiology; gait biomechanics Article  
A Novel Wearable Foot and Ankle Monitoring System for the Assessment of Gait Biomechanics  
[PERSON], P.  
The studied literature, presented as follows, reveals that the framework for evaluating gait biomechanics is based on the plantar pressure distribution and on lower-limb EMG. Under this scenario, the context of our work targets the development of a wearable system for the acquisition of the plantar pressures along the center of pressure (COP) progression line and lower-limb EMG, in order to perform real-time gait monitoring and assessment in an automatic and autonomous fashion. The outcome of this paper is a laboratory proof of concept developed using off the shelf modules and validated in laboratory environment. The novelty of the proposed system consists in the underlying software application which evaluates the cross-correlation between the recorded plantar pressures and lower-limb EMG respectively, aiming to generate a gait map of the individual. As such, plantar pressures recorded with an array of force sensor resistances are cross-correlated to the lower-limb muscular activity extracted from the EMG signals. The cross-correlation results enable the formulation of a gait map which is employed for the assessment of physiological gait. Comparison of the generated gait map to a reference physiological gait map enables to discriminate physiological and pathological gait respectively. The solution proposed in this work is envisioned in the shape of a wearable system, which performs both the monitoring and objective evaluation of foot biomechanics. The proposed approach for the objective evaluation of gait physiology is a novelty in the field. The footprint is basically divided into three regions: forefoot (also accounting for the toes region), midfoot and heel, with the midfoot allowing a further divided into medial and lateral midfoot respectively [3,4]. The footprint accounts for ten anatomical areas which contribute to body weight support and body balance adjustment identified as: toe (1), lesser toes (2), metatarsophalangeal joints (3)-(7), midfoot (8), medial heel (9) and lateral heel (10), as illustrated in Figure 1[5]. These anatomical areas are identified to contribute to body weight support and body balance adjustment. As such, assessment of ground reaction forces and pressures on these areas account for the derivation of lower-limb and whole-body physiological, structural and functional information [6,7].