Klumpke's paralysis (Klumpke palsy): lower brachial plexus injury involving the C8 and T1 nerve roots, sometimes C7.
Cause
Caused by hyperabduction of the arm: a fall on an outstretched hand, the arm pulled into machinery, or a breech delivery with the arm extended.
Claw Hand
Claw hand: from paralysis of the flexors of the wrist and fingers (C6 to C8) and all intrinsic muscles of the hand (C8, T1).
Sensory Loss and Horner's Syndrome
Sensory loss along the medial border of the forearm and hand (T1).
Horner's syndrome: partial ptosis, miosis, anhydrosis and enophthalmos, from involvement of sympathetic fibres to the head and neck leaving the spinal cord via T1.
Horner's syndrome occurs only if T1 is injured proximal to the white ramus communicans to the first thoracic sympathetic ganglion.