Upper Limb II Flashcards
Label this image
What is the spiral groove on the humerus for?
- radial nerve
What does the capitulum of the humerus articulate with?
- radius
Label this image
What are the ulnar medial collateral ligaments in order of strongest to weakest?
- anterior (strongest)
- posterior (weakest)
- oblique (deepens socket)
What is the function of the annular ligament?
- holds the head of the radius in the radial notch of the ulna
What movement does the olecranon fossa limit?
- over extension of the joint
What movement does the coronoid fossa limit?
- full flexion
Label this diagram
Which nerve is at risk of injury with an olecranon fracture?
- ulnar nerve
Identify the distal radioulnar joint. Which aspects of the radius and ulna form this joint?
- between the ulnar notch of the radius and the ulnar head.
What attaches to the Radial styloid process?
- tendon of the brachioradialis attaches at its base,
- radial collateral ligament of the wrist attaches at its apex.
What is the most common fracture in adults over 50 and in what gender?
- Fracture of the distal end of the radius
- occurs more frequently in women because their bones are often weakened by osteoporosis
What is Colles’ fracture?
- A complete transverse fracture within the distal 2cm of the radius
What is seen in Colles’ fracture?
- The distal fragment is displaced dorsally and is often comminuted (broken into pieces).
Why does Colles’ fracture occur?
- forced dorsiflexion of the hand, usually as the result of trying to ease a fall by outstretching the upper limb.
Label these bones
What are the 2 rows of the carpal bones separated by?
- midcarpal joint
Why are falls on an outstretched hand transmitted through the radius?
- wrist joint (radio-carpal joint) involves only the articulation of the distal end of the radius with the Scaphoid and Lunate bones
Why is a fracture of the scaphoid commonly associated with avascular necrosis of the proximal fragment?
- Since the scaphoid blood supply comes from two different vascular branches of the radial artery, fractures can limit access to blood supply
What are the 4 carpal bones in the proximal row?
- Scaphoid
- Lunate
- Triquetrum (triquetral)
- Pisiform
What are the 4 carpal bones in the distal row?
- Trapezium
- Trapezoid
- Capitate
- Hamate
What is a sesamoid bone?
- a bone located within a tendon (i.e. the patella)
Which one of the carpals is a sesamoid bone?
- pisiform
Identify the metacarpals (I-V) and phalanges (I-V) (proximal, middle* and distal)
What 2 carpals are part of the wrist joint complex (radiocarpal joint)?
- scaphoid and lunate
How do the phalanges of the first digit differ from those of the other digits?
- only proximal and distal
Label this image with
1) radiocarpal
2) carpometacarpal
3) metacarpophalangeal
4) interphalangeal joints
What type of joint is the first carpometacarpal joint?
- saddle
What do the carpal bones have on their surface and why?
- concavity on their anterior surface which allows for attachment of the flexor retinaculum
What does the concavity and flexor retinaculum form?
- carpal tunnel
What passes through the carpal tunnel?
- flexor tendons and the median nerve
What is the radiocarpal joint?
- synovial articulation of the concave distal end of the radius with the scaphoid and lunate bones
What actions occur at the wrist?
- flexion
- extension
- abduction
- adduction
- circumduction
Label the palmar aponeurosis
Label these 3 structures
What is the structure in blue?
- flexor retinaculum
Label the structure in blue
- extensor retinaculum
What are the flexor and extensor retinaculums?
- Flexor retinaculum (transverse carpal ligament)
- Extensor retinaculum (thickening of posterior antebrachial fascia)
Label this image
Label the
1) Distal tendon of biceps brachii,
2) Median cubital vein
3) Median antebrachial vein,
4) Median nerve -at this level no branches are given off
5) Brachial artery
6) Bicipital aponeurosis
7) brachioradialis
8) pronator teres
9) ulnar nerve
10) ulnar artery
11) brachioradialis
12) radial nerve
What is the anatomical relationship between the bicipital aponeurosis and the neurovascular structures listed above?
- it passes above them
What divides the forearm into compartments?
- fascial sheath with the interosseous membrane
What is the function of the interosseous membrane?
- strong membrane that attaches the shafts of the radius and ulna to each other
In what direction do the fibers of the interosseous membrane run and why?
- run obliquely so that a force that is applied to the lower end of the radius is transmitted through the radius to the ulna to the humerus and scapula
Label these structures
What is the function of the anterior/flexor compartment of the forearm?
- move the wrist joint
- flex fingers and thumb
- pronate the hand
What is the function of the posterior/extensor compartment of the forearm?
- move the wrist joint
- extend fingers and thumb
- supinate the hand
What are the 4 muscles in the superficial layer of the forearm (flexor/pronator)?
- Pronator teres
- Flexor carpi radialis
- Palmaris longus
- Flexor carpi ulnaris
Where do the superficial muscles attach?
- medial epicondyle