Joints Flashcards
What is the sternoclavicular joint?
synovial articulation between the sternal end of the clavicle and the manubrium of the sternum and the 1st costal cartilage
What is scapulohumeral rhythm?
for every 3 degrees of elevation of the arm, approximately 2 degrees occur at the glenohumeral joint and 1 degree at the scapulothoracic joint
What is the only articulation between the upper limb and the axial skeleton?
The SC joint
What limits elevation of the pectoral girdle?
costoclavicular ligament
What strengthens the SC joint superiorly?
the interclavicular ligament
Where is the interclavicular ligament?
extends from sternal end of one clavicle to the sternal end of the other clavicle; it is also attached to the superior border of the manubrium
What does the costoclavicular ligament do?
anchors the inferior surface of the sternal end of the clavicle to the 1st rib and its costal cartilage
What supplies the SC joint?
internal thoracic and suprascapular arteries
What innervates the SC joint?
medial supraclavicular nerve and the subclavian nerve
What is the classification of the AC joint?
plane synovial articulation
What joint is extremely strong?
SC joint
What joint is relatively weak?
AC joint
What joint is relatively unstable?
glenohumeral joint
What strengthens the AC joint superiorly?
AC ligament
Where is the AC ligament?
extends from the acromion to the clavicle
What does the coracoclavicular ligament do?
maintains integrity of AC joint and prevent the acromion from being driven under the clavicle even when the AC joint is separated;
anchors the clavicle to the coracoid process of the scapula;
suspends scapula and free limb from the clavicle
What are the ligaments of the SC joint?
anterior and posterior SC ligaments, interclavicular ligament, and costoclavicular ligament
What are the ligaments of the AC joint?
AC ligament, coracoclavicular ligament (conoid ligament and trapezoid ligament)
Where is the trapezoid ligament?
attached to the superior surface of the coracoid process and extends laterally and posteriorly to the trapezoid line on the inferior surface of the clavicle
What supplies the AC joint?
suprascapular and thoraco-acromial arteries
What innervates the AC joint?
supraclavicular, lateral pectoral, and axillary nerves
What is the classification of the glenohumeral joint?
ball-and-socket, synovial joint
What are the ligaments of the glenohumeral joint?
glenohumeral ligaments, coracohumeral ligament, transverse humeral ligament, and coraco-acromial ligament
What strengthens the anterior aspect of the glenohumeral joint capsule?
glenohumeral ligaments
What strengthens the glenohumeral joint capsule superiorly?
coracohumeral ligament
Where is the coracohumeral ligament?
passes from the base of the coracoid process to the anterior aspect of the greater tubercle
What does the transverse humeral ligament do?
converts intertubercular sulcus into a canal for the tendon of the long head of biceps brachii and its synovial sheath
Where is the transverse humeral ligament?
runs from the greater to the lesser tubercle, bridging over the intertubercular sulcus
What is the coraco-acromial arch?
extrinsic, protective structure formed by the smooth inferior aspect of the acromion and coracoid process
What does the coraco-acromial arch do?
prevents superior displacement of humerus from the glenoid cavity
What is contracted to prevent further abduction of the humerus without rotation?
coraco-acromial arch
What is ankylosis?
stiffening or fixation of the joints
What are shunt muscles?
act to resist dislocation without producing movement at the joint, or maintain the head of the humerus in the glenoid cavity
What supplies the glenohumeral joint?
anterior and posterior circumflex humeral arteries and branches of the suprascapular artery
What innervates the glenohumeral joint?
suprascapular, axillary, and lateral pectoral nerves
What joints perform extension of the elbow?
Humero-ulnar and humeroradial
What joints produce flexion of the elbow?
Humero-ulnar and humeroradial
What joints produce pronation?
Humeroradial, proximal radio-ulnar, distal radio-ulnar, and the interosseous membrane
What joints produce supination?
Humeroradial, proximal radio-ulnar, and distal radio-ulnar
What classification is the distal radio-ulnar joint?
Synovial, pivot joint
What is the main uniting structure of the distal radio-ulnar joint?
Articular disc
What joint cavity is L-shaped?
Distal radio-ulnar
What innervates the proximal radio-ulnar joint?
Musculotaneous, median, and radial nerves
Pronation is essentially the function of the ____ nerve, whereas supination if the function of the ______.
Median; musculotaneous and radial nerves
What joints are formed by the carpus?
Radiocarpal, intercarpal, carpometacarpal, and intermetacarpal joints
What is the classification of the elbow joint?
hinge synovial joint
What is the classification of the radiocarpal joint?
condyloid synovial joint
What is the classification of the intercarpal joint?
plane synovial
What is the classification of the carpometacarpal joints of the fingers?
plane synovial
What is the classification of the carpometacarpal joint of the thumb?
saddle synovial
What is the classification of the intermetacarpal joints?
plane synovial
What movements occur at the radiocarpal joint?
flexion/extension, abduction/adduction, and circumduction
What movements occur at the intercarpal joints?
small amount of gliding; flexion and abduction of hand
What movements occur at carpometacarpal and intermetacarpal joints?
flexion/extension and abduction/adduction of CMC joint of 1st digit
The radiocarpal, intercarapl, carpometacarpal, and intermetacarpal joints are innervated by what nerve?
anterior interosseous branch of median nerve, posterior interosseous branch of radial nerve, and dorsal and deep branches of ulnar nerve
What is the classification of the metacarpophalangeal joints?
condyloid synovial
What is the classification of the interphalangeal joints?
hinge synovial
The metacarpophalangeal and interphalangeal joints are innervated by what nerve?
digital nerves arising from ulnar and median nerves
