Hand Flashcards
What are the proximal row of carpal bones from lateral to medial called?
Scaphoid
Lunate
Triquetrium
Pisiform
What are the distal row of carpal bones from lateral to medial called?
Trapezium
Trapezoid
Capitate
Hook of hamate
What are the ligaments of that make up the capsule of the wrist joint?
Palmar radiocarpal
Palmar ulnocarpal
Dorsal radiocarpal
Radial and ulnar collateral ligaments
Why is a fraction of the scaphoid clinically important?
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.
What is the carpal tunnel made up of?
Carpal arch (medial is the pisiform and hook of hamate and laterally the tubercles of scaphoid and trapezium) Flexor retinaculum makes up the roof
What passes through the carpal tunnel?
Flexor digitorum profundus
Flexor digitorum superficialis
Flexor pollicis longus
Median nerve
Where do the ulnar artery and ulnar nerve pass?
Anterior to the flexor retinaculum in Guyon’s canal
What is carpal tunnel syndrome?
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.
Where is the muscle palmaris brevis located?
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.
What are the borders of the anatomical snuffbox and what does it contain?
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
Name the intrinsic muscles of the hand
Palmaris brevis, interossei, lumbricals, adductor pollicis, hypothenar and thenar muscles
What are the different group of muscles responsible for the ‘power vs precision’ grip
Power grip: extrinsic muscles of hand
Precision grip: intrinsic muscles of hand
What is the function of the dorsal interossei and how many of them are there?
Abduction of fingers
4
DAB= dorsal abduction
The radial artery passes between the first two.
What is the function of palmar interossei and how many of them are there?
Adduction of fingers
3 (located medial side of index, radial side of ring, radial side of little)
PAD= palmar adduction
What might a lesion of the ulnar nerve result in pathology of the hand?
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