Upper extremity joint Flashcards
What is a saddle type of synovial joint but functions as a ball and joint socket, with the only articulation being between the upper limb and the axial skeleton?
sternoclavicular joint
What does the sternoclavicular joint articulate with?
manubrium and 1st costal cartilage
What is the sternoclavicular joint supplied by?
internal thoracic + suprascapular arteries
What is the nerve supply of the sternoclavicular joint?
branches of the medial supraclavicular nerve + nerve to the subclavius
What is a plane-type joint with the acromial end of the clavicle articulating with the acromion as the scapula?
acromioclavicular joint
What’s the vasculature and nerve for the acromioclavicular joint?
suprascapular and thoracoacromial arteries
lateral pectoral and axillary nerves
What is Hilton’s Law?
joint is innervated by nerves supplying the muscles that act on the joint
What’s a ball and socket type joint where the humeral head articulates w/ the glenoid cavity of the scapula?
glenohumeral joint
Can shoulder separation occur w/o rupture of the coracoclavicular ligament?
no
What’s the joint capsule of the glenohumeral joint?
attached medially to the margin of glenoid cavity and laterally to anatomical neck of humerus; encloses long head of biceps brachii to supraglenoid tubercle of scapula - consider injury can affect biceps
What are the two aperatures of the GH joint?
1) opening between tubercles of humerus (passage of biceps brachii long head tendon)
2) opening anterior and inferior to coracoid process (allows communication)
T/F: the head of the humerus is much larger than the socket
true
What’s the rim of the GH joint?
glenoid labrum - deepens the socket by up to 50%
What are the ligaments of the GH joint?
glenohumeral ligament - 3 fibrous bands, reinforces capsule
Corachohumeral ligament - holds tendon of biceps brachii in place
What is the coracoarcomial arch?
protective structure between acromion and coracoid process w/ coracoacromial ligament
ligament is a protective arch overlying humeral head
What is the vasculature and nerve innervation of the GH joint?
arterial supply - anterior and posterior circumflex humeral, suprascapular artery
nerve: axillary, suprascapular nerve, lateral pectoral nerves
What’s SITS?
S - supraspinatus
I - infraspinatus
T - teres minor
S - subscapularis
What’s the weakest point?
inferior
What’s most often injured of SITS?
supraspinatus
What are the ligaments around the radioulnar joint?
- annular ligament (U shaped, surrounds radius head)
- quadrate ligament (attached to inferior border of radial notch on the ulna and neck of radius)
- radial collateral ligament (lateral epicondyle to annular ligament)
- ulnar collateral ligament (medial epicondyle to coronoid process anteriorly and olecranon posteriorly)
What is the difference in the radial head in children vs adults?
children - small radio head, easy to dislocate
adult - annular ligament rupture if dislocated
What’s a synovial hinge joint that is highly constrained and intolerant and trochlea and capitulum of humerus articulate w/ trochlear notch of the ulna and w/ head of radius?
elbow
What nerves make up the superior nerve of the brachial plexus?
C5 and C6
What nerves make up the middle nerve of the brachial plexus?
C7
What nerves make up the inferior nerve of the brachial plexus?
C8 and T1
What two nerves of the brachial plexus combine to make the lateral nerve?
superior and middle - C5, C6, C7
What three nerves of the brachial plexus combine to make the posterior nerve?
all three - C5, C6, C7, C8
How is the radial nerve innervated?
C5, 6, 7, 8, T1
How is the axillary nerve innervated?
C5, 6
How is the median nerve innervated?
C6, 7, 8, T1
How is the ulnar nerve mediated?
C7,, 8, T1
