<unk> 's<unk>  is a form of<unk>  involving the muscles of the forearm and hand, resulting from a brachial plexus injury in which the eighth cervical (C8) and first thoracic (T1) nerves are injured either before or after they have joined to form the lower trunk. The subsequent<unk>  affects, principally, the intrinsic muscles of the hand (notably the interossei, thenar and hypothenar muscles) and the flexors of the wrist and fingers (notably flexor carpi ulnaris and ulnar half of the flexor digitorum profundus). The classic presentation of<unk> 's palsy is the “claw hand” where the forearm is supinated, the wrist extended and the fingers flexed. If Horner syndrome is present, there is miosis (constriction of the pupils) in the affected eye. The injury can result from difficulties in childbirth. The most common aetiological mechanism is caused by a traumatic vaginal delivery. The risk is greater when the mother is small or when the infant is of large weight. Risk of injury to the lower brachial plexus results from traction on an abducted arm, as with an infant being pulled from the birth canal by an extended arm above the head or with someone catching themselves by a branch as they fall from a tree. Lower brachial plexus injuries should be distinguished from upper brachial plexus injuries, which can also result from birth trauma but give a different syndrome of weakness known as Erb's palsy. Other trauma, such as motorcycle accidents, that have similar spinal cord injuries to C8 and T1, also show the same symptoms of<unk> 's<unk> .
Klumpke paralysis
Periodic paralysis
Cramp fasciculation syndrome
Bobble-head doll syndrome
Ataxic cerebral palsy
Hard flaccid syndrome
Dyskinetic cerebral palsy
Babinski–Nageotte syndrome