The Hand

Question 0

What is the origin, insertion, Innervation, and action of the anductor pollicis brevis.

Answer 0

Flexor retinaculum and tubercles of the scaphoid and trapezium to the lateral side of base of proximal phalanx of thumb.
Innervation: recurrent branch of the median nerve
Actions: abducts the thumb

Question 1

What is the origin, insertion, Innervation, and action of the opponens pollicis?

Answer 1

Flexor retinaculum and tubercles of the scaphoid and trapezium to the lateral side 1st metacarpal.
Innervation: Recurrent branch of the median branch
Action: oppose thumb, it draws the 1 st metacarpal medially to enter the palm and rotates it medially.

Question 2

What is the origin, insertion, Innervation, and action of the flexor pollicis brevis?

Answer 2

Flexor retinaculum, tubercles of the scaphoid and trapezium to lateral side of the base of the proximal phalanx of the thumb.
Innervation: recurrent branch of the the median nerve C8-T1
Action: flexes the thumb

Question 3

What is the origin, insertion, Innervation, and action of the adductor pollicis.

Answer 3

Oblique head: bases of 2nd and 3rd metacarpals, capitate, and adjacent carpals
Transverse head: anterior surface of shaft of 3rd metacarpal to the medial side of the base of the proximal phalanx of the thumb.
Innervation: deep branch of ulnar nerve C8-T1
Actions: adducts thumb toward lateral border of pain.

Question 4

What is the origin, insertion, Innervation, and action of the abductor digiti minimi.

Answer 4

Pisiform to medial side of base of the proximal phalanx of 5th finger
Innervation: deep branch of the ulnar nerve C8-T1
Action: abducts 5th finger and assists in flexion of its proximal phalanx.

Question 5

What is the origin, insertion, Innervation, and action of the opponens digiti minimi.

Answer 5

Hook of the hamate and flexor retinaculum to the medial border of the 5th metacarpal.
Innervation: deep branch of the ulnar nerve C8-T1
Action: draws 5th metacarpal anterior and rotates it bringing 5th fingers into opposition with the thumb

Question 6

What is the origin, insertion, Innervation, and action of the flexor digiti minimi.

Answer 6

Hook of the hamate and flexor retinaculum to the medial side of the base of the proximal phalanx of the 5th finger
Innervation: deep branch of the ulnar nerve C8-T1

Question 7

What is the origin, insertion, Innervation, and action of the lumbricals 1 and 2.

Answer 7

Lateral two tendons of the flexor digitorum profundus to the lateral sides of the extensor expansions of the 2nd and 5th.
Innervation: median nerve C8-T1
Action: flex the metacarpophalangeal joints ; extend interphlangeal joints of the 2nd-5th

Question 8

What is the origin, insertion, Innervation, and action of the lumbricals 3-4.

Answer 8

Medial three tendons of the flexor digitorum profundus to the lateral sides of the extensor expansions of the 2nd and 5th.
Innervation: deep branch of the ulnar nerve C8-T1
Action: flex the metacarpophalangeal joints ; extend interphlangeal joints of the 2nd-5th

Question 9

What is the origin, insertion, Innervation, and action of the dorsal interossei 1-4.

Answer 9

Adjacent sides of two metacarpals to the bases of proximal phalanges, extensor expansions of the 2nd-4th fingers.
Innervation: deep branch of the ulnar C8-T1
Action: abduct 2nd-4th fingers from axial line, act with lumbricals in flexing metacarpophalangeal joints and extending interphlangeal joints.

Question 10

What is the origin, insertion, Innervation, and action of the palmar interossei 1-3.

Answer 10

Palmar surfaces of 2nd, 4th, and 5th metacarpals to bases of proximal phalanges, extensors expansions 2nd, 4th, and 5th fingers.
Innervation: deep branch of ulnar nerve C8-T1
Actions: adduct 2nd, 4th, and 5th fingers toward axial line, assist lumbricals in flexing metacarpophlangeal joints and extending interphalangeal.