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 eletromiografiasuperficiale
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
Optoelectronicsystem-kinematics
Platform -kinetic
EMG –muscularactivity
Video cam –video analysis
Argomenti trattati
I parametri di output della Gait Analysis• I parametri spazio temporali• La cinematica articolare • La dinamica articolare e l’EMG
Kinematics
X,Y,Z
Trajectories
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
-
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
Ff=mfg
Fs=msg
Ft=mtg
Foot
Shank
Thigh -bone
� Ground Reaction Forces
� Gravitational forces
� Inertial forces Fi= -ma
Ffi=- mfa
Fsi=- msa
Fti=-mta
Foot
Shank
Thigh -bone
� Ground Reaction Forces
� Gravitational forces
� Inertial forces
Measured
and computed
Biomech modelForces 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
= F b
Fexb
Mex
Courtesy of the National Institutes of Health - USA
Mex= M int
Mint
M int= ligament and muscles
actions
Forces and moment
INTERNALF e M produced by muscles, ligaments and soft tissues
EXTERNALF e M produced by ground reaction forces, by segments weight and inertial forces
Plan
Dorsi
THE BODY PRODUCES >>>> INTERNAL MOMENTSIN RESPONSE TO >>>>>>>>>EXTERNAL LOADSTHAT PRODUCE>>>>>>>EXTERNAL MOMENTS
EQUILIBRIUM ���� Internal Moments = External Moments
POWER
= M
Mαααα
αααα.
Courtesy of the National Institutes of Health - USA
Power
PowerPower indicates the rate at which a moment is rotat ed
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)
GEN
ABS
Sagittal plane: knee
FIRST PART
Flexion
Extension moment
Absorbed power
Eccentric contraction
of the extensors
SECOND PART
Flexion
Flexion moment
Eccentric contraction
of the gastrocnemius
THIRD PART
Extension
Flexion moment
Absorbed power
Eccentric contraction
of the flexors
Hip joint kinetics
MOVEMENT:
FLEXION
EXTERNAL MOMENT:
EXTENSION MOMENT
INTERNAL MOMENT:
FLEXION MOMENT
FIRST PART
Extension
Extension moment
Generated power
Concentric
contraction extensors
SECOND PART
Extension
Flexion moment
Absorbed power
Silent extensors
� gravity
THIRD PART
Flexion
Flexion moment
Generated power
Concentric
contraction of the
ileopsoas (rectus
femoris)
FOURTH PART
Flexion
Extension moment
Concentric
contraction extensors
Sagittal Plane
Fi= -m*a
Clinical examples
Kinetics
of an hemiplegic child
right hemiplegia
Clinical example - Ankle kinetics
Sagittal plane kinematics and kinetics :ankle
Sagittal plane kinematics and kinetics : knee
Sagittal plane kinematics and kinetics : hip
FX,FY,FZ,
COP
Forces
Torques
Powers
Kinetics
Kinetics
xy
Palestrina, 27 Maggio 2016
EMG
Equipment: EMG
Tibialis Anterior
Gastrocnemius
� Timing
Perry, 1992
EMG signal evaluation
Output of EMG
Reference muscle activity
EMG evaluation
EMG signals
Co-contractions
Timings
…
EMG
EMGKineticsKinematic Video
Thank you