Hand

Question 1

What are the proximal row of carpal bones from lateral to medial called?

Answer 1

Scaphoid
Lunate
Triquetrium
Pisiform

Question 2

What are the distal row of carpal bones from lateral to medial called?

Answer 2

Trapezium
Trapezoid
Capitate
Hook of hamate

Question 3

What are the ligaments of that make up the capsule of the wrist joint?

Answer 3

Palmar radiocarpal
Palmar ulnocarpal
Dorsal radiocarpal
Radial and ulnar collateral ligaments

Question 4

Why is a fraction of the scaphoid clinically important?

Answer 4

Its blood supply is solely from the radial artery which run distal to proximal. A fracture at the waist could cause avascular necrosis of the proximal part.

Question 5

What is the carpal tunnel made up of?

Answer 5

Carpal arch (medial is the pisiform and hook of hamate and laterally the tubercles of scaphoid and trapezium)
Flexor retinaculum makes up the roof

Question 6

What passes through the carpal tunnel?

Answer 6

Flexor digitorum profundus
Flexor digitorum superficialis
Flexor pollicis longus
Median nerve

Question 7

Where do the ulnar artery and ulnar nerve pass?

Answer 7

Anterior to the flexor retinaculum in Guyon’s canal

Question 8

What is carpal tunnel syndrome?

Answer 8

Compression of the median nerve, caused by increased pressure in overuse or swelling of the tendons.
Produces tingling sensation and pain.
Test by tapping median nerve in region of flexor retinaculum to produce these signs (Tinel’s signs).
Weakness and loss of thenar muscle bulk may occur.

Question 9

Where is the muscle palmaris brevis located?

Answer 9

Overlies the hypothenar muscles, ulnar artery and superficial branch of the ulnar nerve.
Originates from the palmar aponeurosis and flexor retinaculum to insert medially in the hand.
Improves grip.

Question 10

What are the borders of the anatomical snuffbox and what does it contain?

Answer 10

Lateral border: Abductor pollicis longus, extensor pollicis brevis
Medial border: Extensor pollicis longus
Floor: scaphoid and trapezium, distal end of tendons extensor carpi radialis longus and brevis

Radial artery passes through

Question 11

Name the intrinsic muscles of the hand

Answer 11

Palmaris brevis, interossei, lumbricals, adductor pollicis, hypothenar and thenar muscles

Question 12

What are the different group of muscles responsible for the ‘power vs precision’ grip

Answer 12

Power grip: extrinsic muscles of hand

Precision grip: intrinsic muscles of hand

Question 13

What is the function of the dorsal interossei and how many of them are there?

Answer 13

Abduction of fingers
4
DAB= dorsal abduction
The radial artery passes between the first two.

Question 14

What is the function of palmar interossei and how many of them are there?

Answer 14

Adduction of fingers
3 (located medial side of index, radial side of ring, radial side of little)
PAD= palmar adduction

Question 15

What might a lesion of the ulnar nerve result in pathology of the hand?

Answer 15

Ulnar claw
Extension at MCP, Flexion at PIP and DIP
There is paralysis of the dorsal and palmar interossei.
The first and second lumbricals can compensate (supplied by median nerve).
Loss of adductor pollicis muscle

Question 16

Where is adductor pollicis located, it’s innervation and function?

Answer 16

Transverse head: anterior shaft surface of metacarpal 3
Oblique head: body of metacarpals 2 and 3
Insert: medial side of proximal phalanx of the thumb
Function: adduction of the thumb and opposition

Question 17

What are the three thenar muscles?

Answer 17

Flexor pollicis brevis
Opponens pollicis
Abductor pollicis brevis
Innervated by recurrent median nerve

Question 18

What are the three hypothenar muscles?

Answer 18

Flexor digiti minimi brevis
Opponens digiti minimi (lies deep)
Abductor digiti minimi
Innervated by deep branch of ulnar nerve

Question 19

Where is the origin go the lumbrical muscles and what do they do?

Answer 19

Originate from the flexor digitorum profundus in the palm.
Insert into the extensor hoods.
Flex the metacarpophalangeal joints.
Extend the interphalangeal joints.

Question 20

What does the ulnar artery supply in the hand and what are its branches?

Answer 20

Deep palmar branch: supplies hypothenar muscles
Superficial palmar branch: palmar digital artery to medial side of little finger, common digital arteries and (join deep palmar arch to form) proper palmar digital arteries.

Question 21

What are the branches of the radial artery in the hand?

Answer 21

Before the hand: dorsal carpal arch, three dorsal metacarpal arteries and first dorsal metacarpal artery
Deep palmar arch -> palmar metacarpal arteries + perforating branches
Princeps pollicis artery
Radialis indicis artery

Question 22

What is Allen’s test?

Answer 22

Testing for inadequate anastomoses between radial and ulnar arteries at the wrist.
Compress one side and then observe filling pattern. If there is little connection, only the thumb and lateral side of index finger will become red when radial artery pressure is released.

Question 23

Which thenar muscle does the ulnar nerve supply?

Answer 23

The adductor pollicis.

Question 24

Where does the superificial ulnar nerve branch supply?

Answer 24

Skin on the palmar surface of the little finger and medial half of ring finger

Question 25

What has a worse prognosis, an ulnar lesion at the elbow or the wrist?

Answer 25

At the wrist; with a lesion at the elbow there is loss of the medial half of flexor digitorum profundus so this leads to lack of flexion at the distal interphalangeal joints.

Question 26

What occurs in radial nerve injury?

Answer 26

Weakened/loss of triceps brachii and muscles in the posterior compartment. Sensory loss of lateral 3 1/2 digits and palmar area -Wrist drop occurs (unopposed flexion of the wrist).