Clinical fenotypes Passive, Active or Reflexive? Neuromechanics of - - PDF document

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Neuromechanics of Movement Disorders Following Stroke

Asbjørn Klomp, J.M. van der Krogt,

• E. de Vlugt, C.G.M. Meskers, J.H. de Groot,

F.C.T. van der Helm, J.H. Arendzen TU Delft / LUMC

Clinical fenotypes

Passive, Active or Reflexive?

Paresis Hypertonia Hyperreflexia Decrease in ROM Dexterity, coordination

Wrist Model

Example: Resistance against movement

Problem Statement

Passive, Active and Reflexive components change over neuromechanical state and input. Obtaining an estimate of their properties requires different measurement conditions.

Methods: materials

Perturbation: force / position Neuromuscular modeling System identification Neuronal & muscular parameters Force, position and EMG Task instruction: force / position / EMG

Methods: Protocol

Passive Active Reflexive Integral (Pass., Act. & Refl.)

• ROM (pas.)
• Stiffness in rest
• Stiffness under

voluntary contraction

• Spinal reflex time (M1, M2)
• Ashworth
• Wide Band (WB) multi-sine

force perturbations

• ROM (act.)
• MVC
• Force to failure

Passive + Active

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Pilot Results

Wide Bandwidth, multisine force perturbations

Patient Healthy Green = Relax Blue = Resist Red = Resist + damped environment

Meskers, 2009

Red = ETFE Blue = Model fit Dot = Healthy Circle = Patient

Schouten, de Vlugt 2006

Pilot Results

0.094

[0.045]

0.024

[0.052]

0.137

[0.184]

• Rep. 2

0.105

[0.041]

0.026

[0.066]

0.101

[0.053]

• Rep. 1

Patient 0.121

[0.041]

0.023

[0.049]

0.067

[0.076]

• Rep. 2

0.182

[0.081]

0.026

[0.036]

0.067

[0.037]

• Rep. 1

Healthy Resist (+Damp) Relax Resist Estimated Reflexgain (kv)

[Estimate of SEM]

Pilot Results

• Ashworth

(1sec./ROM & .5sec./ROM)

Patient Healthy

W O R K I N P R O G R E S S

Conclusions

We presented an approach for discrimination between passive tissue, active muscular and reflexive neuromechanical properties, in different conditions.

Future Work

• Improve understanding of clinical

fenotype development from identified neuromuscular parameters

• Use the parameters to improve

treatment

• Nonlinear identification techniques

Sponsors

EXPLICIT website: www.explicit-stroke.nl E-mail: a.klomp@lumc.nl

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EXPLICIT

Brain Movement Biomechanical: tendomuscular changes Neurological: altered spinal reflex loop properties Corticospinal tract Peripheral reflex loop Neuromechanics

fMRI TMS Haptic Robot Kinematics/ clinical scales Supraspinal lesion Movement disorder

Protocol

Viscoelastic, passive Muscle, active Neural, controller

• P. ROM
• P. Stiffness
• A. Stiffness

MVC Neural Loop WB Ashworth

• A. ROM

Passive sweep through the ROM in:

• 1.0 Seconds
• 0.5 Seconds

Pilot Results

• Stiffness in Rest

Pilot Results

• Force to Failure