GHJ joint type
Synovial joint rotating around 3 axes
Humeral head positioning
-facing medially, posteriorly, superiously
Angle of inclination
-the head is inclined approximately 130* from long axis of shaft
Retroversion
-rotation of the humeral head in the transverse plane is 30*
Glenoid fossa position
7* laterally from scapula and oriented posteriorly with a slight 5* superior tilt relative to medial border of scapula
Labrum
GHJ capsule
along with ligaments have double the surface area of the humeral head itself
-capsule arises form glenoid neck and labrum - inserts on articular margin of anatomical neck of humeral head (except inferomedially where it extends down the humeral neck)
2 openings in GHJ capsule
1) between humeral tubercles allowing biceps tendon to exit the joint
2) connection between joint and subscapularis bursa
Inferior GHJ capsule
-very redundant to allow for greater ROM
Anterior & Posterior capsule
- extracapsular ligaments surround superior and anterior joint
Superior GH ligament
-either a robust or thin tissue that provides restraint to inferior translations of humeral head when arm is adducted
Middle GH ligament
-restraint to anterior humeral translation with the arm in mid-range of abduction up to about 45* and also limits ER with arm at side
Inferior GH ligament complex
Scapulothoracic joint
- between anterior scapula and posterior thorax and rib cage
Scapula superior and inferior border and scapular angles
Sternoclavicular joint
SC joint disc
SC joint capsule
- weak and supported by thickenings called AP SC ligaments
Posterior SC ligament
-causes significant increases in AP translations - greater than that of any ligament
Interclavicular ligament
- thought to provide restrains to inferior forces on medial end of clavicle
Costoclavicular ligament
-anterior and posterior bundles that run from superior surface of the first rib to the undersurface of clavicle
AC joint
AC joint capsule
-surrounds to help provide stability
Conoid and trapexoid ligaments (coracoclavicular ligaments)
-provide stability medial to the AC joint