Overview Introduction Standard: C5, C6, C7, C8, T1 – 77% of patients Prefixed: Prefixed (contributions from C3, C4) – 22% Postfixed (roots caudal to T1) – 1% COMPOSITION: “Robert Turner Drinks Cold Beer” Roots (5): ventral rami of C5-T1, superior and posterior to subclavian dorsal scapular nerve (C5): through levator scapula to supply levator scapula, rhomboid major & minor long thoracic nerve (C5, 6, 7): posterior to plexus onto thoracic wall to supply serratus anterior Trunks (3): emerge from triangle formed by anterior scalene, middle scalene, first rib superior (C5,6 roots) suprascapular nerve (C5, 6): through suprascapular notch to supraspinatus, infraspinatus, AC and glenohumeral joints nerve to subclavius (C5, 6) Erb's palsy login to view 2 more bullets middle (C7) inferior (C8, T1) Divisions (6): 3 anterior, 3 posterior (each trunk gives 1 anterior and 1 posterior division) Cords (3): Posterior Cord: formed from 3 posterior division upper subscapular nerve (C5, 6): subscapularis lower subscapular nerve (C5,6): subscapularis, teres major thoracodorsal nerve (C6, 7, 8): latissmus dorsi Lateral Cord: ant divisions of superior & middle trunks (C5, 6, 7) lateral pectoral nerve (C5, 6, 7): supplies medial aspect of pectoralis major, communication with medial pectoral nerve Medial Cord: anterior division of inferior trunk (C8, T1) Branches (6) – 2 terminal branches from each cord medial pectoral nerve (C8, T1): pierces pec minor; supplies pec minor and lateral aspect of pec major medial brachial cutaneous nerve (T1) medial antebrachial cutaneous nerve (C8, T1) Posterior cord: login to view 2 more bullets Lateral cord: login to view 2 more bullets Medial cord: login to view 2 more bullets