Normal Gait and Dynamic Function purpose of the foot in ambulation Edward P. Mulligan, PT, DPT, OCS, SCS, ATC Assistant Professor; Residency Chair UT Southwestern School of Health Professions Department of Physical Therapy Dallas, TX The contents of this presentation are copyrighted 2002 by. They may not be utilized, reproduced, stored, or transmitted in any form or by any means, electronic or mechanical, or by any information storage or retrieval system, without permission in writing from Edward P. Mulligan. flexible adaptation to the terrain dissipate ground reaction forces (shock absorption) lower extremity internal rotation Normal Gait and Dynamic Function purpose of the foot in ambulation SUPINATION (stable platform) rigid lever for propulsion provide stable base of support for LE weight transfer lower extremity external rotation Stance Phase 60% of gait cycle heel strike - foot flat - heel rise - toe off Phase 40% of gait cycle early (acceleration) mid - terminal (deceleration) swing Gait Cycle (Stride) Gait Cycle (Stride) Stance Stance Weight Acceptance Single Limb Support Limb Advancement IC LR MSt TSt PSw ISw MSw TSw Heel Contact Foot Flat Midstance Heel Off Toe Off Early - Mid - Late Terminal Heel Off Heel Strike Foot Flat
lower extremity kinematics Pelvis: (R) CCW; Fwd Translation; Ant Rotation Hip: Flexion; Adduction; Internal Rotation Knee: Flexion; Valgus; Tibial Internal Rotation Ankle: Dorsiflexion Subtalar: Calcaneal Eversion; Talar Adduction and plantarflexion Midtarsal: Unlocking First Ray: Unlocking lower extremity kinematics SUPINATION Pelvis: (R) CW; Bwd Translation; Posterior Rotation Hip: Extension; Abduction; External Rotation Knee: Extension; Varus; Tibial External Rotation ti Ankle: Plantarflexion Subtalar: Calcaneal Inversion; Talar Abduction and df Midtarsal: Locking First Ray: Locking heel strike to foot flat plantarflexes from neutral under eccentric control of the pretibial muscles Subtalar/Midtarsal Joints pronates from slightly supinated position to unlock the midfoot and allow foot adaptation to the terrain knee flexes and tibia internally rotates from full extension at heel strike following the directional input of the STJ joint midstance tibia moving over foot as dorsiflexion increases Subtalar/Midtarsal Joints supination progressing back towards neutral just prior to heel off. Foot changing from loose adapter to rigid lever. knee is extending and tibia is externally rotating to maximum range at heel off propulsion rapid maximal plantarflexion Subtalar/Midtarsal Joint maximally supinated MTP Joints - toes extending rapidly flexing in preparation for swing phase of gait swing phase dorsiflexes back to neutral Subtalar Joint pronates back to just mildly supinated position at heel strike knee extending in preparation for heel strike
sagittal plane frontal plane transverse plane Walking vs. Running Kinematics
CONTRAST of WALKING JOGGING RUNNING PARAMETER WALKING JOGGING RUNNING Speed 2-4 mph 5-9 mph 10+ mph Stance Time Duration.6 sec.3 sec.2 sec Vertical Forces Body weight 2-3 x BW 2-3 x BW Support Phase double limb support single limb support single limb support Stance: 3:2 3:4 1:2 Time Ratio Base of Gait 2-3 cm 1 cm None or crossover Running Has float phase More time in swing than stance General Trends (from walking to jogging to running) Functional Gait Analysis SAGITTAL FRONTAL TRANSVERSE Total ROM Increases Duration of Gait Cycle Decreases Velocity of Joint Motion Increases Long Stride Wide Stance Hips IR Low Ceiling Crossover Gait Charlie Chaplin Arms Overhead Scythe Figure 8 Increase speed of gait Alter cervical or shoulder position or motions
simple evaluation parameters to recognize STJ position during gait SUPINATION Posterior View: calcaneal eversion calcaneal inversion lateral calcaneal indentation lateral calcaneal indentation concave to midline convex to midline Anterior View: internal rotation of tibia external rotation of tibia Lateral View: talar head add/pfs medial longitudinal arch bulging medially heightens Contact Phase Heel strike laterally to forefoot loading Vertical ground reaction forces at maximum IR of lower leg Anterior tibial musculature firing eccentrically TCJ moving from DF position to slight PF Post Tib and Gastroc-Soleus firing eccentrically to decelerate STJ pronation and tibial IR Transverse Tarsal Joint relatively unrestricted Midstance Phase Full weight reception of forefoot to heel lift Eccentric contraction of posterior superficial compartment and soleus to control forward movement of the tibia Concentric contraction of post tib and gastroc to cause STJ supination and tibial ER Decrease in vertical GR forces 75% BW BW borne by one foot Foot becoming rigid lever Propulsion Concentric Phase Heel lift to toe off STJ supination and continuation of ER of leg Vertical GR forces peak (125% BW) Toes bear weight Weight relieved from 5th metatarsal head after heel lift Weight shift lateral to medial forefoot Phase Toe off to heel strike Leg ER after toe off initially, then IR STJ pronates first half and supinates second half Observe open chain mechanics