h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Abe Goldberg, a somewhat severe Glasgow consultant physician used to line up about 10 or 12 of us in the middle of the ward to teach us the areas of skin supplied by each segment of spinal nerves starting from the neck (cervical) area. With each chanted letter and number movement you slap the area of skin (or clothing over it ) quite loudly. The first cervical (C1) doesn't supply any skin.

C2 - Stand upright, hands on the back of your head.
C3 - Hands down to the back of the neck
C4 - Cross arms, fingers on shoulder tips
C5 - Left hand out in front of you, run R fingers down forearm
C6 - R forefinger to left thumb
C7 - R forefinger to left mid
C8 - R forefinger to left 5th and sweep up inner arm to the elbow
T1 - inner arm elbow to armpit
T2 to 6 - Both thumbs on collar bones then swiftly to 5th finger on rib margin
T7 to 12 - hands from rib margin to groin
L1 - bend forward, both hands over upper inner thigh
L2 - bend further, both hands over inner thigh just above knee
L3 - both hands over outer thigh
L4 - bend further, hands over inner calf
L5 - hands to outer calf
L6 - hands up the back of the calf from ankle to knee
S1 - hands up the back of the thigh from knee to buttock
S2 to 4 - Slap buttocks loudly

The patients by this time were in hysterics at our antics (good therapy) and we learned (through our embarassed grins) something we would use throughout our career. I still run through bits of it (mentally ) if I'm not quite sure where a particular pain is coming from or where a particular band of shingles originates.

(T = thoracic, L = lumbar, S = sacral nerve roots: working down the spine)