Rock-paper-scissors.

A study of 20 doctors in their first or second postgraduate year highlighted deficiencies in their knowledge of the nerve supply of the hand and forearm. The children's game rock-paper-scissors (Figs. 1-3) can be used as a simple aide-memoir for the nerve supply to the hand and forearm. The median nerve creates the "rock position" of the pronated fist (Fig. 1). The radial nerve extends the wrist and hand forming the "paper position" (Fig. 2a and b) and the ulnar nerve creates the "scissor position" (Fig. 3), by clawing the ring and little fingers and spreading the index and middle and adducting the thumb and flexing the interphalangeal joint.