Erbs palsy

Erbs palsy

Lesion?

Erb's palsy (Erb-Duchenne Palsy) is a paralysis of the arm caused by injury to the upper group of the arm's main nerves, specifically the upper trunk C5-C6 is severed.

Causes?

^·          from shoulder dystocia during a difficult birth.^[4]

The paralysis can be partial or complete; the damage to each nerve can range from bruising to tearing. The most commonly involved root is C5 (aka Erb's point: the union of C5 & C6 roots)^[8] as this is mechanically, the furthest point from the force of traction, therefore, the first/most affected.^[6] 

Erb-Duchenne palsy presents as alower motor neuron syndrome associated with sensibility disturbance and vegetative phenomena. ^[9]

The most commonly involved nerves are the suprascapular nerve, musculocutaneous nerve, and the axillary nerve.^[10][11]

Signs:

·         The signs of Erb's Palsy include loss of sensation in the arm and paralysis and atrophy of the deltoid, biceps, and brachialis muscles.^[8] "

·         The position of the limb, under such conditions, is characteristic: the arm hangs by the side and is rotated medially; the forearm is extended and pronated.

·         The arm cannot be raised from the side;

·         all power of flexion of the elbow is lost, as is also supination of the forearm".^[6] 

·         The resulting biceps damage is the main cause of this classic physical position commonly called "waiter's tip."

http://orthoinfo.aaos.org/topic.cfm?topic=a00077