May22 M3-Shoulder and back Flashcards
3 bones of the elbow
scapula, humerus, clavicle
two processes of the upper part of the humerus
greater tubercle lateral
lesser tubercle medial
three processes of the scapula
- spinous process (in the back, medial to lateral towards the top)
- acromion (from spinous process reaching top), on roof of shoulder
- coracoid process (process going anteriorly in top anterior of scapula)
landmarks on the scapula
- triangle so has 3 borders (for ex medial border. other would be superior and lateral)
- superior and inferior angle of the scapula
axial skeleton def
pelvis, vertebral column, sternum, ribs, etc.
only bone of the shoulder that articulates with the axial skeleton (and with what bone)
clavicle. articulates with the sternum
name of articulation between clavicle and sternum + supporting ligament
- sternoclavicular joint
- costoclavicular ligament (from rib 1 to the clavicle)
what does the sternoclavicular joint allow (movement)
- protraction and retraction of the shoulder girdle (scapula + clavicle complex) (moving forward and backward)
- elevation and depression of the shoulder girdle
- abduction and adduction of the shoulder girdle
articulations involved in reaching something anteriorly by putting the arm straight forward (protraction, retraction)
sternoclavicular joint only
charact of the sternoclavicular joint
articulation = 1 cm diameter articular disk (so is a NARROW joint. not much contact surface)
steps of ABDuction of the shoulder
- at rest, clavicle at 90 deg angle with humerus
- first 30 deg: mvmt at humerus-scapula (glenohumeral) joint (humerus rotating), clavicle and scapula not moving
- 30-170deg: clavicle elevation at the sternoclavicular joint (scapula will rotate PASSIVELY bc attached to the clavicle)
- 170+ deg: external upwards lateral rotation of the scapula
rule when visualizing and describing movement of a joint in anatomy
movements done in the anatomical position. palms of hand facing forward
movements that the humerus can do at the shoulder joint independently of the clavicle and the scapula, other than ABDuction and ADDuction
- flexion and extension (arm straight + lift arm straight to front or back in anat position)
- medial (internal) rotation and lateral (external rotation) with elbow at 0 deg flexion or 90 deg flexion)
2 sets of ligaments that reinforce the stability of the shoulder girdle
- acromio-clavicular ligament between acromion and clavicle
- coraco-clavicular ligaments (coracoid process to clavicle).: one shape of trapeze one shape of cone
function of the acromio-clavicular ligament and the coraco-clavicular ligaments
- keep scapula and clavicle close during movement (ex. elevation of clavicle during 30-90 deg abduction)
- is what attaches the clavicle to the scapula
name of the portion of the scapula that articulates with the humerus + name of the articulation
glenoid cavity
-glenohumeral joint
portion of the humerus that articulates with the glenoid cavity of the scapula
head (with big bump medially)
problem of glenoid cavity + compensating mechanism
flat so humerus can easily dislocate
- ring of cartilage called the LABRUM at the articulation to support it
- glenohumeral capsule (is a ligament wrapping around the joint)
- tendons of the long head of biceps and tendon of the rotator cuff muscles (that of long head of biceps travels humerus to scapula + travels in capsule) and
name of the type of joint that the glenohumeral joint is
bone and socket joint
function of the coraco-acromial ligament (note is same bone to same bone. scapula to scapula)
prevents superior dislocation of the humerus
structures around the shoulder joint that help reduce friction between bone + one example
bursas (synovial membranes forming a bursa with synovial fluid)
e.g. subacromial bursa (under the acromion)
4 muscles of the rotator cuff and common origin+insertion
subscapularis, supraspinatus, infraspinatus, teres minor
all scapula to humerus
subscapularis location, origin, insertion, function
- between scapula and ribs
- scapula to humerus
- medial rotation of the arm (humerus)