Pronator drift is a sign of -

Ans. is 'a' i.e., UMN lesion of upper limb o Ask the patient to close his or her eyes, then to stretch out both arms with the palms facing up # The patient should maintain this position for 20-30 seconds, o Observe both arms If the motor pathways are intact, the arms should remain in this position equally. o Patients with slight weakness in one arm won V be able to keep the arm raised and ultimately the palm may begin to pronate or turn downward. This is pronator drift" which indicates an abnormal function of the corticospinal tract. Pronator drift occurs in patients with cerebral injury or cer\'ical cord lesions. Also know Lateral drift o In lateral drift, the arm moves up or laterally. o This is a sign of loss of proprioception (position sense) which is mediated by spinothalamic tract.