shoulder, humerus and elbow Flashcards
find diagram and label all parts the humerus, shoulder and elbow
what are the 4 joints found in the shoulder
- Gleno-humeral joint
- acromioclavicular joint
- sternoclavicular joint
- scapula-thoracic joint
what type of joint is the Glenn-humeral joint
synovial ball and socket
what type of joint is the acromioclavicular joint
synovial plane
what type of joint is the sternoclavicular joint
synovial saddle
what is different about the scapula-thoracic joint compared to the 3 other shoulder joints
- not a TRUE anatomical joint
- its a junction between scapula and thoracic cage
- concave surface of inferior scapula glides across the convex surface of the thoracic cage
what areas can be palpitated on the clavicle
- acromioclavicular joint
- sternoclavicular joint
what areas can be palpitated on the scapular
- spine of scapula
- coracoid process
- inferior angle of scapula
what areas can be palpitated on the humerus
- head of humerus
- bicipital groove
- distal humeral epicondyle
what areas can be palpitated on the ulna
olecranon process
what is expected of an AP humerus XRAY
- elbow and shoulder joints
- humeral head and greater tubercle in profile
- outline of lesser tubercle seen between the humeral head and greater tubercle
- soft tisse
what is expected of a lateral humeral xray
- elbow and shoulder joints
- superimposed humeral epicondyles
- greater tuberosity superimposed over humeral head
- soft tissue
what should be seen on an AP shoulder xray
- soft tissue margins
- greater tuberosity on lateral side of humerus
- outline of lesser tuberosity between humeral head and greater tubercle
- humeral head
- acromioclavicular joint space
what is there bicipital groove also known as
inter tubercular groove
how can you tell if the humerus is rotated or not on a shoulder xray
- if externally rotated, greater tubercle is more lateral
- if neutral, greater tuberosity remains on the lateral side with less tuberosity seen in middle of humeral head
- if internally rotated, greater tuberosity is seen on medial side of humeris
what is difference in purpose of an AP shoulder and a true ap shoulder
- ap = see the acromioclavicular joint space plus other AOI
- true = see the Glenn-humeral joint space plus other AOI
What should be seen on an AP elbow xray
- radial head, neck and tuberosity slightly superimposed over proximal ulnar
- elbow joint space clear
- no rotation of humeral epicondyles
- soft tissue margines
how can you tell if the humerus is rotated in an elbow scan
- if the coronoid and olecranon fossa is approximately equidistance to epicondyles
what should you see on a lateral elbow xray
- elbow joint space clear and open
- superimposed humeral epicondyles
- radial tuberosity facing anteriorly
- olecranon process in profile
what are the 4 muscles of the rotator cuffs
- supraspinatous
- infraspinatous
- subscapularis
- teres minor
find a diagram and label the 4 rotator cuffs
where is the origin of the supraspinatous muscle and where does it attach to
- origin = supraspinous fodda
- inserts at the capsule of shoulder and greater tuberosity
what is the innervation of the supraspinatous muscle + what landmark
- supra scapular nerve
- c5/c6
what is the function/purpose of the supraspinatous muscle
- abduction of arm in shoulder
- resists downward force of gravity and weight-bearing
- stabilises humeral head into glenoid fossa
where is the origin of the infraspinatous muscle and where does it attach to
- infraspinous fossa
- capsule and middle facet of greater tuberosity of humerous
what is the innervation of the infraspinatous muscle + what landmark
- axillary nerve
- c5/c6
what is the function/purpose of infraspinatous muscle
- lateral rotates arm
- upper fibres abduct arm at shoulder
- lower fibres adduct arm at shoulder
- stabilises humeral head into glenoid fossa
where is the origin of the teres minor muscle and where does it attach to
- upper 2/3 dorsal surface of lateral border of scapula
- capsule and lower facet of greater tuberosity of humerus
innervation of teres minor?
- supra scapular nerve
- c5/6
purpose/function of teres minor?
- laterally rotates arm
- weak adductor of arm at shoulder
- stabilises humeral head into glenoid fossa
where is the origin of the subscapularis muscle and where does it attach to
- sub scapular fossa on anterior surface of scapular
- capsule and to lesser tuberosity of humerus
innervation of subscapularis + landmark
- upper and lower sub scapular nerves
- c5/6
function/purpose of subscapularis
- medially rotates arms
- assists in all ranges of movement depending on arm position
- stabilises humeral head into glenoid fossa
what is a hill-sacks fracture
- an injury that occurs secondary to an anterior shoulder dislocation
- humeral head ‘collides’ with the anterior part of the glenoid, causing a lesion, bone loss, defect and deformity of the humeral head
what shoulder projection would you do to identify a hill-sacks fracture
axial
what shoulder view would you to see a fractured humeral neck
Y shoulder view
what shoulder projection would you do to see fractures scapula especially the acromion
axial
what are the 2 standard clavicle views
- ap
- 30 degrees cranial view
why would you angle the tube 30 degrees cranially for a clavicle xray
straightens out the clavicle and projects most of it above the scapula and second and third rib
if there is a large gap between the receptor and patient armpit when doing a axial shoulder (maybe due to injury and inability to abduct wide), what can be done to compensate/ reduce magnification
increase the SID
how can over or under rotation of the torso affect the shoulder anterior oblique ( Y projection ) image
the ribs will be superimposed over region of intrest
