Hand Flashcards
How many interphalangeal joints does the thumb have?
1
What is the function of the collateral ligaments of the MCP, PIP and DIP joints?
Provide lateral stability
What are the 4 bones of the proximal row of bones of the hand?
Scaphoid
Lunate
Triquetrum
Pisiform
What are the 4 bones of the distal row of the bones of the hand?
Trapezium
Trapezoid
Capitate
Hamate
What kind of joint is the carpometacarpal joint?
Saddle joint
- specifically adapted to allow a wide range of movements
What are the extrinsic muscles of the hand?
The forearm flexors and extensors
Which 5 compartments of the hand are the intrinsic muscles located in?
Thenar Hypothenar Adductor Central Interosseus
Which nerve innervates the thenar muscles?
Median nerve (recurrent branch)
Which nerve innervates the adductor pollicis?
Ulnar nerve
What is the function of the adductor pollicis muscle?
Adduction of the thumb - provides grip
What are the thenar muscles of the hand?
Opponens pollicis
Abductor pollicis brevis
Flexor pollicis brevis
What are the hypothenar muscles of the hand?
Abductor digiti minimi
Flexor digiti minimi brevis
Opponens digiti minimi
Which nerve innervates the hypothenar muscles?
Ulnar nerve
What are the lumbricals?
Each of 4 lumbricals is associated with a finger
They link the flexor and extensor tendons
Where do the lumbricals originate from?
A tendon of the flexor digitorum profundus
Which nerve innervates the lateral 2 lumbricals?
Median nerve
Which nerve innervates the medial 2 lumbricals?
Ulnar nerve
What are the two groups of interossei and what are their functions?
Palmar - adduction of fingers
Dorsal - abduction of fingers
Which nerve innervates the dorsal interossei?
Ulnar nerve
Which nerve innervates the palmar interossei?
Ulnar nerve
What does the median nerve supply?
Thenar muscles
First and second lumbricals
What does the ulnar nerve supply?
Hypothenar muscles
Third and fourth lumbricals
Adductor pollicis
All interosseus muscles
What does the radial nerve supply in the hand?
No motor branches
But does send sensory branches to dorsal aspect
What is the blood supply to the hand?
Radial artery
Ulnar artery
What is the venous drainage of the hand?
Superficial/ deep venous palmar arch –> cephalic vein
What is skier’s thumb?
Injury to ulnar collateral ligament of metacarpophalangeal joint
(Fall on outstretched thumb)
What is mallet finger?
Tear of tendon that straightens end of finger
What is trigger finger?
Finger locks as it is bent towards palm
Due to thickening of mouth of a tendon tunnel - tendon catches in it
More common in Type 1 diabetics and RA patients
What is Dupuytren’s contracture?
Shortening, thickening, fibrosis of palmar fascia
often 4th and 5th digits
Which joint of the hand is commonly affected by osteoarthritis?
Joint between the metacarpal and trapezium bones (base of thumb)
Due to loss of cartilage
What is the difference in joints affected by rheumatoid arthritis vs osteoarthritis?
Osteoarthritis preferentially affects distal pharangeal joints
