Brachial Plexus — Complete Summary

Roots: C5–T1. Trunks: • Upper (C5, C6) • Middle (C7) • Lower (C8, T1) Divisions: Anterior and Posterior from each trunk. Cords: • Lateral — anterior divisions of Upper + Middle trunks • Posterior — all posterior divisions • Medial — anterior division of Lower trunk Key Terminal Nerves: • Musculocutaneous → Lateral cord • Axillary → Posterior cord • Radial → Posterior cord • Median → Lateral + Medial cords • Ulnar → Medial cord Classic Injuries: • Erb's palsy (C5, C6) → waiter's tip position • Klumpke's palsy (C8, T1) → claw hand