Site of injury
Lower trunk of Brachial plexus
Causes
Undue abduction of arm while clutching something with hands after a fall from height or birth injury
Nerve roots involved
C8-T1
Muscles involved
Intrinsic muscles of hand (T1) & Ulnar flexors of wrist and fingers (C8)
Deformity
Claw hand
Disability
- Cutaneous anaesthesia and analgesia along the ulnar border of forearm and hand
- Horner’s syndrome (Ptosis, Miosis, Anhydrosis on the ipsilateral side)
- Vasomotor changes: Skin area with sensory loss is dry and warm due to absence of sweating and arteriolar dilatation respectively (Loss of sympathetic activity)
- Trophic changes: Dry and scaly skin on long standing. Cracking of nails and atrophy of pulp of the fingers
– Jainam Shah