La Gait Analysis grandezze dinamiche e casi clinici. Manuela Galli, DEIB, POLITECNICO DI MILANO

La Gait Analysis grandezze dinamiche e casi clinici. Manuela Galli, DEIB, POLITECNICO DI MILANO

Programma 3. La valutazione del cammino Gait analysis 3.1. Obiettivi della valutazione quantitativa del cammino in ambito clinico. 3.2. Protocolli e standard internazionali. 3.3 Introduzione alla valutazione del report di prove di gait analysis : parametri spazio temporali e grafici di cinematica articolare. 3.4 Prova pratica di Gait Analysis 3.5 Valutazione dei tracciati di dinamica articolare e di eletromiografia superficiale 4. Applicazioni cliniche dell analisi del movimento in ambito clinico 4.1. La Gait Analysis nel bambino con PCI 4.2. Analisi del movimento nel paziente con Malattia di Parkinson 4.3 Analisi del movimento nel paziente con Sclerosi Multipla.

Motion analysis lab Video cam video analysis Optoelectronic systemkinematics Platform - kinetic EMG muscular activity

Argomenti trattati I parametri di output della Gait Analysis I parametri spazio temporali La cinematica articolare La dinamica articolare e l EMG

Kinematics Trajectories X,Y,Z Velocities Accelerations Angles,

Kinematic

Argomenti trattati I parametri di output della Gait Analysis I parametri spazio temporali La cinematica articolare La dinamica articolare e l EMG

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Kinetics evaluation : the ground reactions forces P

KINETICS DESCRIBE THE CAUSES OF THE MOVEMENT Ground Reaction Forces Measured

GROUND REACTION FORCES and COP Ant/posterior Medial/lateral Vertical CoP

Ground Reaction Forces Gravitational forces

F t =m t g Thigh-bone F s =m s g Shank F f =m f g Foot

Ground Reaction Forces Gravitational forces Inertial forces F i = -ma

F ti =-m t a Thigh-bone F si =- m s a Shank F fi =- m f a Foot

Ground Reaction Forces Gravitational forces Inertial forces Measured and computed

Forces Biomech model Joint Moment

MOMENT OF FORCE A force acting at a distance from the rotational center causing the body to rotate M = F x D

MOMENT M int b F ex = F b M ex M ex = M int M int= ligament and muscles actions Courtesy of the National Institutes of Health - USA

Forces and moment INTERNAL F e M produced by muscles, ligaments and soft tissues EXTERNAL F e M produced by ground reaction forces, by segments weight and inertial forces

Plan Dorsi

EQUILIBRIUM Internal Moments = External Moments THE BODY PRODUCES >>>> INTERNAL MOMENTS IN RESPONSE TO >>>>>>>>>EXTERNAL LOADS THAT PRODUCE>>>>>>>EXTERNAL MOMENTS

Power M α POWER = M α. Courtesy of the National Institutes of Health - USA

Power Power indicates the rate at which a moment is rotated Power = Moment x Angular Velocity Power = Force x Distance x Angular Velocity [W]

Generated power > 0 Momentum and movement are in the same direction Flex-extension velocity increases Muscle concentric contraction (the contracting muscle shortens under tension) Absorbed power < 0 Momentum and movement are not in the same direction Flex-extension velocity decreases Muscle eccentric contraction (the contracting muscle lengthens under tension)

ABS GEN

Sagittal plane: knee FIRST PART Flexion Extension moment Absorbed power SECOND PART Flexion Flexion moment THIRD PART Extension Flexion moment Absorbed power Eccentric contraction of the extensors Eccentric contraction of the gastrocnemius Eccentric contraction of the flexors

Hip joint kinetics

MOVEMENT: FLEXION EXTERNAL MOMENT: EXTENSION MOMENT INTERNAL MOMENT: FLEXION MOMENT

Sagittal Plane FIRST PART Extension Extension moment Generated power SECOND PART Extension Flexion moment Absorbed power THIRD PART Flexion Flexion moment Generated power FOURTH PART Flexion Extension moment Concentric contraction extensors Silent extensors gravity Concentric contraction of the ileopsoas (rectus femoris) Concentric contraction extensors

Fi= -m*a

Clinical examples Kinetics of an hemiplegic child right hemiplegia Pdf

Clinical example - Ankle kinetics

Sagittal plane kinematics and kinetics :ankle

Sagittal plane kinematics and kinetics : knee

Sagittal plane kinematics and kinetics : hip

Kinetics Forces FX,FY,FZ, COP Torques Powers Kinetics y x

EMG Palestrina, 27 Maggio 2016

Tibialis Anterior Gastrocnemius Equipment: EMG

EMG signal evaluation Timing Perry, 1992

Output of EMG

Reference muscle activity

EMG evaluation Co-contractions EMG signals Timings EMG

Kinematic Kinetics EMG Video

Thank you