- Anatomy:
-
C-8 & T-1 anterior nerve roots convey
preganglionic sympathetic fibers for innervation of head & neck
to corresponding spinal nerves, from which they pass to ganglionated sympathetic chain;
- further laterally these 2 spinal nerves acquire bulk of postganglionic fibers for the hand and arm;
- injury of
C-8 & T-1 nerve roots does not affect sympathetic innervation of arm but interrupts those to same side of head
causing vasodilatation, anhydrosis, & dilated pupil (Horner's syndrome);
