Deep Muscles of Posterior Forearm

Question 0

Abductor Pollicis Longus

Answer 0

Origin: Radius, Ulna, Interosseous Membrane
Insertion: Base of 1st Metacarpal
Action: Abducts the Hand at the Wrist and Thumb
Nerve: Radial (via Deep Branch)

Question 1

Supinator

Answer 1

Origin: Lateral Epicondyle of Humerus, Proximal Ulna, Annular Ligament of Radius
Insertion: Lateral Upper Radius
Action: Supinates Forearm and Hand
Nerve: Radial (via Deep Branch)

Question 2

Extensor Pollicis Brevis

Answer 2

Origin: Radius, Interosseous Membrane
Insertion: Base of the Proximal Phalanx of Thumb
Action: Extends Proximal Phalanx of Thumb
Nerve: Radial (via Deep Branch)

Question 3

Extensor Pollicis Longus

Answer 3

Origin: Ulna, Interosseous Membrane
Insertion: Base of the Distal Phalanx of Thumb
Action: Extends Distal Phalanx of Thumb
Nerve: Radial (via Deep Branch)

Question 4

Extensor Indicis

Answer 4

Origin: UIna, Interosseous Membrane
Insertion: Middle and Distal Phalanges of 2nd Digit via Extensor Expansions
Action: Extends 2nd Digit
Nerve: Radial (via Deep Branch)