Often due to prolonged compression of the arm. Typical causes are overdose and alcohol intoxication.

Motor paresis: Wrist drop—paresis of wrist and thumb extensors.

Sensory loss and pain: Dorsum of hand.

Loss of deep tendon reflex: Brachioradialis.

Guillain-Barré syndrome is also known as acute idiopathic inflammatory polyneuropathy.

Acute onset.

Symmetric weakness, usually beginning in the legs, and more marked proximally than distally.

Some sensory complaints.

Typical absence of deep tendon reflexes. There may be marked autonomic dysfunction.

Nerve conduction study: Slow conduction velocity, prolonged distal motor latency, and conduction blockade.

Cerebrospinal fluid (CSF): Increased protein concentration but a normal cell count.

It prevents the release of acetylcholine vesicles from presynaptic nerve terminals. In this way it reduces muscle spasm.

Fibrillations.

Positive sharp waves.

Pain and sensory deficits of the palmar surface.

Sensory deficits are confined to the median nerve distribution, and primarily involve the thumb, the index and middle fingers, and the lateral half of the ring finger.