Expansion
Lateral two lumbricals by the median nerve, medial two by the ulnar nerve
Mnemonic
LOAF for the muscles of the hand supplied by the median nerve:
- L - Lateral two lumbricals
- O - Opponens pollicis
- A - Abductor pollicis brevis
- F - Flexor pollicis brevis
Everything else in the hand is ulnar. The lumbricals therefore split their supply down the middle: the lateral two are median, the medial two are ulnar, which mirrors the sensory division of the hand at the ring finger.
Expansion
- Lateral two lumbricals (index and middle) - median nerve
- Medial two lumbricals (ring and little) - ulnar nerve
This “one-and-a-half plus two-and-a-half” pattern mirrors the sensory split of the hand between median and ulnar territories.