MSK anatomy 2 Flashcards
Joints of the shoulder girdle? (3)
* Acromioclavicular
* Sternoclavicular
* Glenohumoral
2 processes of scapula?
* Acromion
* Coracoid process
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Which ligaments are torn in acromioclavicular joint dislocation?
Coracoclavicular ligaments
Which muscle moves the scapula?
Origin?
Insertion?
Innervation?
Trapexius = elevates, depresses + retracts scapula
* Origin = ~T1 - T12
* Insertion = occiput + spine of scapula
* Innervation = spinal accessory nerve
Diseases affecting glenohumoral joint? (3)
Which patients are affected by AC?
* OA + RA
* Dislocation
* Adhesive capsulitis = diabetic patients + following trauma
What is the purpose of the labrum of the shoulder joint?
What is it susceptible to?
Deepens socket and increases stability
Susceptibel to labral tears
* SLAP tears - where long head of biceps tendon anchors to labrum
* BANKART lesion - inferior anterior labral tear
What do rotator cuff muscles do?
Hold humeral head in glenoid fossa + move the arm
Origin of supraspinatus muscle?
Insertion?
Innervation?
Function?
* Origin = supraspinous fosssa
* Insertion = greater tuberosity of humerus
* Innervation = suprascapular nerve
* Function = abducts arm first 15*
Origin infraspinatus muscle?
Insertion?
Innervation?
Function?
* Origin = infraspinous fossa
* Insertion = greater tuberosity of humerus
* Innervation = suprascapular nerve
* Function = external rotation
Teres minor origin?
Insertion?
Innervation?
Function?
* Origin = posterior surface of lateral border of scapula
* Insertion = greater tuberosity of humerus
* Innervation = axillary nerve
* Function = external rotation
Subscapularis origin?
Insertion?
Innervation?
Function?
* Origin = anterior surace of scapula
* Insertion = lesser tuberosity of humerus
* Innervation = SUBscapular nerve
* Function = INTERNAL rotation
Rotator cuff muscles susceptible to? (2)
* Tears
* Impingement
Deltoid origin?
Insertion?
Innervation?
Function?
* Origin = clavicle, acromion + spine of scapula (anterior, middle and posterior deltoid)
* Insertion = deltoid tuberosity on lateral aspect of humerus
* Innervation = axillary nerve
* Function = abducts arm
Biceps brachii origin?
Insertion?
Innervation?
Function?
* Origin: short head = coracoid process, long head = labrum
* Insertion = tuberosity of radius
* Innervation = musculocutaneous nerve
* Function = flexes elbow, SUPINATES forearm
* radial head always on lateral side
* Coronoid on ulnar (medial) side
What is elbow joint susceptible to? (3)
Radial head/neck?
* OA + RA
* Dislocation
* OLECRANON fracture
Radial head/neck susceptibel to fracture
What does radial head attach to?
Ulnar head?
What is the coronoid process?
* Radial head -> capitulum
* Ulnar head -> trochlea
* Coronoid process is projection from ulna
Olecranon fracture
What is the supracondylar region?
What group of people are supracondylar fractures common in?
Region above the medial and lateral epicondyles in elbow
* Children
Which part of the elbow is commonly affected by bursitis?
Olecranon bursa
Ligaments of the elbow? (3)
* Medial collateral ligamanets
* Lateral collateral ligament
* Annular ligament
Why is the lateral epicondyle of the humerus significant?
What is it susceptible to?
site of insertion for all of the extensor muscles of the forearm
* Susceptible to enthesiopathies i.e. tennis elbow
Why is the medial epicondyle of the humerus significant?
What is it susceptible to?
site of insertion for all of the flexor muscles of the forearm
* susceptible to enthesiopathies i.e. golfers elbow
Do not get confused between radial styloid (wrist) and radial head (elbow)
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What is the function of the triangular fibrocartilage complex in the hand? (2)
Shock absorption and lubricating function
Distal radius fracture also known as?
Colles fracture
Blood supply to scaphoid?
Scaphoid has retorgrade blood supply (meaning it is suceptible to AVN - same reason why femoral head is susceptible to AVN)
*
What is unusual about the healing of scaphoid fractures?
The more distal the fracture is, the more likely it is to heal (usually the opposite for most fractures) - due to unusual retrograde blood supply
Scaphoid fracture
Thumb does not have an intermediate phalynx
Thenar muscles function?
What are they? (3)
Innervation?
Move the thumb
* Opponens pollicis
* Flexor pollicus brevis
* Abductor pollicus brevis
Inervation = median nerve
…
Hypothenar muscle function?
What are they? (3)
Innervation?
Move pinky
* Abductor digiti minimi
* Opponens digiti minimi
* Flexor digiti minimi brevis
Innervation = ulnar nerve
Interossei muscle function?
Innervation?
ALL flex MCPs and extend IPs
Individual functions = DAB and PAD
* Dorsal interossei (x4) - Abduct fingers
* Palmar interossei (x3) - adduct fingers
Innervation = ulnar nerve
Lumbricals function?
Innervation?
Lumbricals (x4) = one for each finger, finger movement
* Innervation = lateral 2 (median nerve), medial 2 (ulnar nerve)
Flexor digitorium superficialis function?
Innervation?
What does it pass thru?
Flexes fingers at PIPs
* Innervation = median nerve
* Passes thru carpal tunnel
Flexor digitorum profundus function?
Innervation?
Passes thru?
Flexes fingers at DIPs
* Innervation: 2nd + 3rd digits = median nerve, 4th and 5th = ulnar nerve
* passes thru carpal tunnel
Pulley system of hand?
What are they susceptible to?
Annular ligaments (A1 - A5)
* A2 and A4 most important (prevent bowstringing)
* A1 most commonly involved in trigger finger
Cruciate pulleys (x3 - cross shaped)
* prevent sheath collapse during motion
susceptible to triggering
Function of palmar fascia?
Susceptible to? (2)
Seperates palmar muscle bellies and flexor tendons from skin
* Susceptible to hypertophy and fibrosis (Dupuytren’s)
Blood supply to hand?
Digits?
Radial artery + ulnar artery
* Radial digital artery + ulnar digital artery (named after side of the digit not the artery they come from)
Peripheral nerves of hand? (3)
What do they supply?
Diagram
Median, ulnar + radial nerves
* Suppply extrinsic/intrinsic muscles of hand + give cutaneous sensation
Median nerve supplies? (2)
Tests? (2)
Muscular supply
* Flexors of forearm
* LOAF muscles (Lateral lumbricals, opponens pollicus, abductor pollicus brevis, flexor pollicus brevis)
* TEST = abductor pollicus brevis
Cutaneous sensation
* Radial 3.5 digits
* TEST = tip of index finger + base of thenar muscles
Ulnar nerve supplies?
Test?
Muscular supply
* Small muscles of the hand (intrinsics i.e. medial lumbrcals + interossei)
* Hypothenar muscles
* TEST = abductor digiti minimi
Cutaneous supply
* Ulnar 1.5 digits
* TEST = dorsum and volar aspects of pinky
Radial nerve supplies?
Test?
Muscular supply
* extensors of forearm
* TEST = extensor indicis
Cutaneous sensation
* Variable portion of dorsum of hand
* TEST = dosrum of 1st webspace
What can problem with radial nerve lead to?
Wrist drop
Examples of compressive neuropathies? (2)
* Cubital tunnel syndrome at elbow
* Carpal tunnel syndrome at wrist
What is cubital tunnel formed by?
What passes thru?
Formed by 2 heads of flexor carpi ulnaris + arcuate ligament
* Ulnar nerve
Which nerve causes funny sensation in hand when elbow is banged off table?
Ulnar nerve
