Hand & Wrist Anatomy

Question 1

State the carpal bones of the hand

Answer 1

She looks too pretty, try to catch her

Scaphoid, lunate, triquetrum, pisiform, trapezium, trapezoid, capitate, hamate

Question 2

Describe the boundaries of the carpal tunnel

Answer 2

Superior boundary - flexor retinaculum (attaches to scaphoid, pisiform, trapezium, hamate)
Inferior boundary - carpal bones

Question 3

State the contents of the carpal tunnel

Answer 3

4 flexor digitorum superficialis tendons
4 flexor digitirum profundus tendons
Flexor pollicis longus
Medial nerve

Question 4

State the thenar eminence muscles

Answer 4

Opponens pollicis, abductor pollicis brevis, flexor pollicis brevis

Question 5

Opponens pollicis - AFI

Answer 5

Attachments - originates from trapezium and flexor retinaculum and inserts into metacarpals
Actions - thumb opposition
Innervation - median nerve

Question 6

Abductor pollicis brevis - AFI

Answer 6

Attachments - originates from scaphoid, trapezium and flexor retinaculum and inserts into proximal phalanx and extensor hood
Actions - thumb abduction
Innervation - median nerve

Question 7

Flexor pollicis brevis - AFI

Answer 7

Attachments - originates from trapezium and flexor retinaculum and inserts into proximal phalanx
Actions - thumb flexion
Innervation - median nerve

Question 8

State the hypothenars muscles

Answer 8

Opponens digiti minimi, abductor digiti minimi, flexor digiti minimi

Question 9

Opponens digiti minimi - AFI

Answer 9

Attachments - originate from hamate and flexor retinaculum inserts into metacarpals
Actions - opposition of 5th metatarsal
Innervation - ulnar nerve

Question 10

Abductor digiti minimi - AFI

Answer 10

Attachments - originates from pisiform and inserts into proximal phalanx
Actions - abduction of 5th metatarsal
Innervation - ulnar nerve

Question 11

Flexor digiti minimi - AFI

Answer 11

Attachments - originates from hamate and flexor retinaculum and inserts into proximal phalanx
Actions - flexion of 5th metatarsal
Innervation - ulnar nerve

Question 12

Lumbricals - AFI

Answer 12

Attachments - originates from flexor digitorum profundus and insert into extensor hood
Function - flexion of MCP joint and extension at IP joints
Innervation - medial two lumbricles innervated by ulnar nerve
Lateral two lumbricles innervated by median nerve

Question 13

Interossei muscles - AFI

Answer 13

Attachments - originate from metacarpals and insert into extensor hood
	3/4 in the palmar, 4 in the dorsal
Function - PAD DAB
	Palmar interossei cause adduction
	Dorsal interossei cause abduction 
Innervation - ulnar nerve

Question 14

Palmaris brevis - AFI

Answer 14

Attachments - originates from palmar aponeurosis and flexor retinaculum and inserts into skin
Action - improves grip
Innervation - ulnar nerve

Question 15

Adductor pollicis - AFI

Answer 15

Attachments - originates from metacarpal II, III and capitate and inserts into proximal phalanx and extensor hood of thumb
Action - adducts thumb
Innervation - ulnar nerve

Question 16

Describe the blood supply of the hand

Answer 16

• The radial and ulnar arteries enter the hand and split into the superficial and deep palmar arches
  
  • They anastomose with the corresponding branches from the other artery
• Superficial palmar arch gives off the common palmar digital arteries which supply the fingers

Question 17

Describe the Allen’s test

Answer 17

Pressing the ulnar or radial artery and then releasing
For normal blood flow, hand quickly becomes warm and returns to its normal colour
One artery alone enough to supply entire hand
For abnormal flow, hand remains cold and pale

Question 18

What does the median nerve supply in the hand

Answer 18

Supplies radial 3 and a half of digits - thumb to half of ring finger 
   Superficial to tendons
	LOAF - lateral two lumbricals
		Opponens pollicis
		Abductor pollicis brevis
                Flexor pollicis brevis

Question 19

What does the ulnar nerve supply in the hand

Answer 19

Covered by flexor carpi ulnarus
Supplies little finger and half of ring fingers
Innervates all muscles apart form LOAF

Question 20

What does the radial nerve supply in the hand

Answer 20

Supplies back of hand with sensation

Question 21

State the borders and contents of the anatomical snuffbox

Answer 21

Lateral Border= tendons of abductor pollicis longus and extensor pollicis brevis
Medial Border= tendon of extensor pollicis longus
Floor= scaphoid bone
Roof= skin
Proximal border= styloid process of radius
Contents= radial artery, superficial branch of radial nerve, cephalic vein