Opponens Pollicis : Origin, Insertion, Action & Nerve Supply

The opponens pollicis is a small, triangular muscle in the hand, which functions to oppose the thumb. It is one of the three thenar muscles, lying deep to the abductor pollicis brevis and lateral to the flexor pollicis brevis.

Attachment of the Opponens Pollicis

Origin:
originates from the flexor retinaculum of the hand and the tubercle of the trapezium.
Insertion:
It passes downward and laterally and is inserted into the whole length of the metacarpal bone of the thumb on its radial side.

Nerve Supply of the Opponens Pollicis

Recurrent branch of median nerve (C8 and T1)

Blood supply Opponens Pollicis

Superficial palmar arch.

Function of the Opponens Pollicis

1.The opposition of the thumb toward the digits(Primary action)

• Antagonists: Extensor Pollicis Longus, Extensor Pollicis Brevis, Abductor Pollicis Longus
• Agonists: Abductor Pollicis Brevis, Adductor Pollicis, Flexor Pollicis Brevis

2. Flexion of the thumb at the carpometacarpal joint(Secondary action)

• Agonists: Adductor Pollicis, Flexor Pollicis Longus, Flexor Pollicis Brevis
• Antagonists: Abductor Pollicis Longus, Extensor Pollicis Brevis