Muscles Origins, Insertions, Innervations, and Actions: HAND

Question 1

Origin and Insertion of Palmaris Brevis

Answer 1

Origin: Flexor retinaculum; medial border of palmar aponeurosis
Insertion: Skin on ulnar border of palm

Question 2

Innervation and Action of Palmaris Brevis

Answer 2

Innervation: Superficial branch of ulnar nerve
Action: Folds the skin of the ulnar side of the palm

Question 3

Origin and Insertion of Abductor Digiti Minimi

Answer 3

Origin: Pisiform Bone
Insertion: Medial side of proximal phalanx of digit 5

Question 4

Innervation and Action of Abductor Digiti Minimi

Answer 4

Innervation: Ulnar nerve
Action: Abducts digit 5

Question 5

Origin and Insertion of Flexor Digiti Minimi Brevis

Answer 5

Origin: Hook of Hamate, flexor retinaculum
Insertion: Base of proximal phalanx of digit 5

Question 6

Innervation and Action of Flexor Digiti Minimi Brevis

Answer 6

Innervation: Deep branch of ulnar nerve
Action: Flexion at joints of digit 5

Question 7

Origin and Insertion of Opponens Digiti Minimi

Answer 7

Origin: Flexor retinaculum, hook of hamate
Insertion: Ulnar border of 5th metacarpal

Question 8

Innervation and Action of Opponens Digiti Minimi

Answer 8

Innervation: Ulnar nerve
Action: Opposition of digit 5

Question 9

Origin and Insertion of Abductor Pollicis Brevis

Answer 9

Origin: Flexor retinaculum, scaphoid, and trapezium
Insertion: Radial base of proximal phalanx of digit 1

Question 10

Innervation and Action of Abductor Pollicis Brevis

Answer 10

Innervation: Median nerve, recurrent branch
Action: Abducts digit 1

Question 11

Origin and Insertion of Opponens Pollicis

Answer 11

Origin: Flexor retinaculum, scaphoid, and trapezium
Insertion: Lateral border of metacarpal bone of digit 1

Question 12

Innervation and Action of Opponens Pollicis

Answer 12

Innervation: Median nerve
Action: Opposition of thumb

Question 13

Origin and Insertion of Flexor Pollicis Brevis

Answer 13

Origin: Superficial head: flexor retinaculum and trapezium; Deep head: deep branch of ulnar nerve
Insertion: Radial side of base of proximal phalanx of digit 1

Question 14

Innervation and Action of Flexor Pollicis Brevis

Answer 14

Innervation: Superficial: Median nerve; Deep: deep branch of ulnar nerve
Action: Flexes proximal phalanx of digit 1

Question 15

Origin and Insertion of Adductor Pollicis

Answer 15

Origin:2nd and 3rd metacarpal and capitate
Insertion: Medial surface of base of proximal phalanx of digit 1

Question 16

Innervation and Action of Adductor Pollicis

Answer 16

Innervation: Ulnar nerve, deep branch
Action: Adducts digit 1

Question 17

Origin and Insertion of Lumbricals

Answer 17

Origin: Tendons of the flexor digitorum profundus
Insertion: Extensor expansion of same digit

Question 18

Innervation and Action of Lumbricals

Answer 18

Innervation: 1&2- median nerve; 3&4- ulnar nerve
Action: Flexes metacarpophalangeal joint; extends proximal and distal interphalangeal joints

Question 19

Origin and Insertion of Dorsal interossei

Answer 19

Origin: Trapezium
Insertion: Base of proximal phalanges and dorsal expansions of digits 2-4

Question 20

Innervation and Action of Dorsal interossei

Answer 20

Innervation: Ulnar nerve
Action: Abduction at metacarpophalangeal joints of digits 2-4

Question 21

Origin and Insertion of Palmar interossei

Answer 21

Origin: One head from metacarpals of digits 2, 4, 5
Insertion: Dorsal digital expansion of digits 2, 4, 5

Question 22

Innervation and Action of Palmar interossei

Answer 22

Innervation: Ulnar nerve, deep branch
Action: Adduction at metacarpophalangeal joint of digits 2 and 4