Everyday Muscle.

Lateral Head of Flexor Pollicis Brevis

Hand
Has dual innervation — median and ulnar — which is why thumb function can survive either nerve injury.
Function
Flexes MCP joint of thumb
Origin
Trapezium and flexor retinaculum (deep head from trapezoid/capitate)
Insertion
Base of proximal phalanx of thumb (lateral side)
Innervation
Deep head: deep branch of ulnar nerve (C8-T1)
Learn this region Quiz this region
Flexor Digitorum Profundus Extensor Digitorum Extensor Indicis Flexor Pollicis Longus Extensor Pollicis Longus Extensor Pollicis Brevis Abductor Pollicis Longus Adductor Pollicis Opponens Pollicis Opponens Digiti Minimi (Hand)