ANATOMY
Medicine Made Simple
, Nerves – Upper Limb
Brachial plexus
Plexus of nerves formed by the ant. Primary rami of the C5, C6, C7, C8, T1 nerve
roots with contributions from the C4 and T2 nerve roots.
Roots – ant. Primary rami of C5 to T1
Trunks – upper, middle, lower
Divisions – ventral and dorsal divisions of each trunk
Cords – lateral, medial, posterior
Prefixed plexus -contribution by C4 is large
- T₁ is reduced in size
-T2 is often absent
post fixed plexus -contribution by T1 is large
-T2 is always present
-C4 is absent
-C5 is reduced in size
ROOTS between ant. & middle scaleni
TRUNKS Posterior triangle of neck
DIVISIONS behind middle 1/3 of clavicle
CORDS & BRANCHES axilla (within the axillary sheath so UL anesthesia)
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