QS Study

Features of Lesion of any part of Pyramidal Tract

Pyramidal tracts originate in the cerebral cortex, carrying motor fibers to the spinal cord and brain stem. They are responsible for the voluntary control of the musculature of the body and face. An example of a classic disorder of the pyramidal system is a stroke, resulting in paralysis of an extremity.

Fig: Pyramidal Tract

Effect of lesion of the pyramidal tract

Lesion of pyramidal tract above the pyramidal decussation product contralateral symptoms and lesions below this level produce ipsilateral symptoms of the body. Effects are –

On voluntary movement:

  • Disturbance of voluntary movements especially in arm and leg.
  • The discrete movements of the fingers, walking grasping, scratching etc. cannot be properly performed.

On muscle tone:

  • Increases (Spastic paralysis) due to release phenomenon

On reflexes:

  • Superficial reflexes are absent deep reflexes are exaggerated.

On the Babinski sign: Positive.