Clinical Applicability of an Existing Proportionality Scheme in Three-Segment Kinetic Foot Models

The Biomechanical Behavior of Distal Foot Joints in Patients with Isolated, End-Stage Tibiotalar Osteoarthritis Is Not Altered Following Tibiotalar Fusion

“…The kinetic computation combined the marker position, ground reaction force, and plantar pressure data. The center of pressure and resultant ground reaction force were distributed over four segments of the Rizzoli Foot Model (rearfoot, midfoot, forefoot, and hallux segment) using a proportionality scheme [ 14 ]. This was furthermore validated in a similar patient population [ 14 ].…”

“…The center of pressure and resultant ground reaction force were distributed over four segments of the Rizzoli Foot Model (rearfoot, midfoot, forefoot, and hallux segment) using a proportionality scheme [ 14 ]. This was furthermore validated in a similar patient population [ 14 ]. Inertial parameter calculations of foot segments were based on the mass of the segments and on their geometric solids, whereas the mass of the foot was distributed at 30/30/30/10% for the rearfoot/midfoot/forefoot/hallux respectively.…”

“…The inter-segment joint angles were defined as follows: ankle joint (between the shank and rearfoot segment), Chopart joint (between the rearfoot and midfoot segment), Lisfranc joint (between the midfoot and forefoot segment) and the first metatarsophalangeal joint (MTP 1; between the forefoot and hallux segment). An inverse dynamic analysis program written in Matlab (MathWorks, Natick, MA, USA) computed joint moments and powers starting from the hallux segment and progressing proximally using Newton–Euler equations, similar to a recent methodology published by Deschamps et al [ 13 ] and Eerdekens et al [ 14 ]. All one-dimensional data (waveforms) were normalized to 100% of the stance phase, and the mean was calculated based on the four recorded trials per subject.…”

“…In the past, this has been difficult, due to technical limitations in three-dimensional (3D) gait analysis [ 12 ]. Recent efforts led to the development of novel, 3D, multi-segment kinetic foot models that have the possibility to quantify the biomechanical functioning of the complete ankle and foot complex [ 13 , 14 ]. These can furthermore provide us with an enhanced understanding of the functional adaptations of adjacent foot joints in patients with end-stage tibiotalar OA after surgical fusion.…”

Blood‐induced cartilage damage alters the ankle joint load during walking

“…3 First, the position of the foot markers was projected on the floor in order to determine the boundaries of the three respective foot segments, being the rearfoot, midfoot and toe segments. For all of these segments, center of pressure and resultant GRF, derived from combining force and pressure platform data, were computed for each frame of the segmented pressure data by estimating subarea shear forces and normal moment as a proportion of the measured normal forces using the proportionality scheme previously validated by Eerdekens et al 21 So, for any given segment i:…”