Upper limb - Hand muscles (MSK)

Question 1

Intrinsic muscles

Answer 1

Originate and terminate within the hand itself

Question 2

Extrinsic muscles

Answer 2

Act on the and and the wrist but don’t originate from the hand

Question 3

Thenar eminence

- Muscles

Answer 3

• Base of the thumb

- Includes: Abductor pollicis brevis, flexor pollicis brevis, opponens pollicis

Question 4

Abductor pollicis brevis

Origin, insertion, innervation, action

Answer 4

• Flexor retinaculum
• Proximal phalanx of the thumb
• Median nerve
• Abducts the thumb
• Occurs In coronal plane

Question 5

Flexor pollicis brevis

Origin, insertion, innervation, action

Answer 5

• Flexor retinaculum
• Proximal phalanx of the thumb
• Median nerve
• Flexor of the thumb

Question 6

Opponens pollicis

Origin, insertion, innervation, action

Answer 6

• Flexor retinaculum
• Distal metacarpal of the thumb
• Median nerve
• Opposition of the thumb and pinky

Question 7

Hypothenar eminence

- Muscles

Answer 7

Abductor digiti minimi, flexor digiti minimi, opponens digiti minimi

Question 8

Abductor digiti minimi

Origin, insertion, innervation, action

Answer 8

• Flexor retinaculum
• Proximal phalanx of the pinky
• Ulnar nerve
• Abducts the pinky

Question 9

Flexor digiti minimi

Origin, insertion, innervation, action

Answer 9

• Flexor retinaculum
• Proximal phalanx of the pinky
• Ulnar nerve
• Flexor of the pinky

Question 10

Opponens digiti minimi

Origin, insertion, innervation, action

Answer 10

• Flexor retinaculum
• Distal metacarpal of 5th digit (pinky)
• Ulnar nerve
• Opposition of pinky and thumb

Question 11

Palmar interossei

Origin, insertion, innervation, action

Answer 11

• Originate from metacarpals
• Proximal phalanx and extensor expansion hood
• Ulnar nerve
• Adduction of fingers
• 3 muscles total (3 for Pal)

Question 12

Dorsal interossei

Origin, insertion, innervation, action

Answer 12

• metacarpals
• Proximal phalanx and extensor expansion hood
• Ulnar nerve
• Abduction of the digits
• 4 in total (4 for dors)

Question 13

Adductor pollicis

Origin, insertion, innervation, action

Answer 13

• Metacarpal 3
• Proximal phalanx of the thumb
• Ulnar nerve
• Adduction
• triangular muscle

Question 14

lumbricals

Origin, insertion, innervation, action

Answer 14

• Tendons of flexor digitorum profundus
• Extensor expansion hood
• Lateral 2 innervated by the median nerve and medial 2 are innervated by the ulnar nerve
• Flexion (metacarpal) and extension (interphalanegal joints)
• 4 total

Question 15

HALF LOAF

Answer 15

• All muscles in the hand are innervated by the ulnar nerve except:

Half of the lumbricals (medial innervated by ulnar lateral by median)

opponens pollicis

abductor pollicis brevis

Flexor pollicis brevis