Joints of Upper LImb - Ch. 15 Flashcards
sternoclavicular joint
- synovial, saddle joint
- articulates with: manubrium, costal cartilage of 1st rib, sternal end of clavicle
- ligaments keep clavicle from popping up
- articular cartilage is fibrocartilage and is VERY strong
ligaments of sternoclavicular joint
- articular capsule
- A/P sternoclavicular ligament (weeker)
- interclavicular ligament (continuous across jugular notch)
- costoclavicular lig. (1st rib–>medial inferior portion of clavicle) : this limits elevation of medial end of clavicle
what limits excessive movment of clavicle?
- subclavius muscle and costoclavicular ligament work together to do this.
fibrocartilageinous articular disk
divides sternoclavicular joint into two joint cavities - it is important for modification for joint stability.
- functions to cushionjoint and prevent upward and medial dislocation –> the two joint cavities increase overall motion
acromioclavicular joint
- synovial - plane (gliding) - doesn’t move much
- ligaments: articular capsule, superior/inferior acromioclavicular ligaments, coracoclavicular ligament
Coracoclavicular ligament
- strongest of ligaments stabilizing acromioclavicular joint
- anchors clavicle to coracoid process
1. conoid part: more medial
2. trapezoid part: lateral
Glenohumeral joint
- synovial; ball and socket
- articulates with glenoid cavity of scapula and head of humerus
ligaments: articular capsule, coracohumeral ligament, coracoacromial ligament, transverse humeral ligament
articular capsule of glenohumeral joint
thin and loose, contributes to joint flexibility in all ROMs
coracohumeral ligament
helps prevent inferior dislocation
coracoacromial ligament
helps prevent superior dislocation of glenohumeral joint
glenohumeral bands/ligaments
internal aspect of anterior wall of jiont capusle. they prevent anterior and posterior inferior dislocation
elbow joint
- synovial hinge joint
- articulates: trochlea of humerus with trochlear notch of ulna, capitulum of humerus with head of radius, head of radius with radial notch of the ulna
- contains articular capuslue, ulnar collateral ligaments and radial collateral ligaments
ulnar collateral ligaments
(makes a triangle on intermedial part of of elbow
- anterior part (strongest)
- posterior part (weaker)
- oblique/transverse part (weakest)- helps close semilunar notch of ulna medially
ulnar collateral ligaments
(makes a triangle on intermedial part of of elbow
- anterior part (strongest)
- posterior part (weaker)
- oblique/transverse part (weakest)- helps close semilunar notch of ulna medially
articular capsule of elbow joint
- weak anteriorly and posteriorly (in range of motion), but is strongly reinforced by collateral ligaments
articular capsule of elbow joint
- weak anteriorly and posteriorly (in range of motion), but is strongly reinforced by collateral ligaments
radial collateral ligament
lateral portion of elbow
- from lateral epicondyle to annular ligament of radius
radial collateral ligament
lateral portion of elbow
- from lateral epicondyle to annular ligament of radius
proximal radioulnar joint
- synovial - pivot joint
- articulates head of radius and radial notch of ulna
- shares joint capsule with elbow joint - strengthened by attachments of anterior capsular and lateral collateral ligaments of the elbow joint
- ligaments: annular ligament
proximal radioulnar joint
- synovial - pivot joint
- articulates head of radius and radial notch of ulna
- shares joint capsule with elbow joint - strengthened by attachments of anterior capsular and lateral collateral ligaments of the elbow joint
- ligaments: annular ligament
intercarpal joints
- synovial/plane
- articulates between carpals of proximal row and carpals of distal row
annular ligament
encircles head of radius and attaches to ulna above and interior to radial notch - not main supporter
distal radio-ulnar ligament
- synovial, pivot joint
- artciulations between head of ulna and ulnar notch of radius
- has capsular ligaments (weak) and fibrocartilaginous articular disk (attaches distal radius to ulnar styloid process)
interosseous membrane
- spans radius and ulna - these fibers pass inferiorly and medially from radius to ulna
- due to the strong structure of the elbow and distal radio-ulnar joint, the interosseous membrane resists the tendency of two bones to be forced in opposite directions
- the strong articulations are at the ulnar-elbow connection and radial-wrist connection - force is applied to these areas due to the fiber direction
radio-carpal joint
- synovial, ellipsoidal/condyloid
- articulates distal radius and articular disk of distal radiolunar joint with the scaphoid, lunate and triquetrum (not psiform at all!)
- ligaments: articular capsule, palmar/dorsal radiocarpal lig, ulnocarpal ligament, radial and ulnar collateral ligaments
humeroscapular rhythm
1-2 degrees of scapular rotation for every 2-3 degrees of glenohumeral rotation
- 90 degrees of abduction = 60 degrees humeral rotation, 30 degrees of scapular rotation
- abduction is initiated by supraspinatus and deltoid to 90 degrees of abduction
- rotation of scapula above 90 degrees is by trapezius and serratus anterior
- lateral rotation by infraspinatus and teres minor
mid-carpal joint
- exists because there are no interosseous ligaments between the proximal and distal row of carpals - this joint allows for increased flexibility of the wrist during flexion, extension and opposition
interphalangeal joints
synovial, hinge joints (flexion/extension)
Note: they are strengthened dorsally by passage of extensor expansion and extensor digitorum tendons
deep transverse metacarpal ligament
- keeps metacarpals aligned
- unites palmar surface of heads of metacarpals 2-5
- creates webbing of fingers
shoulder abduction: ROM, GH/scapular/humeral rotation?
- ROM: ball and socket joint, shallow glenoid cavity, loos fibrous capsule
- Glenohumeral rotation: deltoid, rotator cuff muscles
- Scapular rotation: trapezius, serr. anterior
- humeral rotation: infraspinatus, teres minor
humeroscapular rhythm
1-2 degrees of scapular rotation for every 2-3 degrees of glenohumeral rotation
- 90 degrees of abduction = 60 degrees humeral rotation, 30 degrees of scapular rotation
- abduction is initiated by supraspinatus and deltoid to 90 degrees of abduction
- rotation of scapula above 90 degrees is by trapezius and serratus anterior
- lateral rotation by infraspinatus and teres minor
metacarpophalangeal joints
synovial condyloid joint
- articulates heads of all metacarpals to bases of five proximal phalanges
- dorsally the metacarpophalangeal joints are strengthened by passage of tendons of extensor digitorum and extensor pollicis longus and brevis
interphalangeal joints
synovial, hinge joints (flexion/extension)
Note: they are strengthened dorsally by passage of extensor expansion and extensor digitorum tendons
Shoulder
Strength/Power: deltoid
Stability: Rotator cuff muscles
Flexibility: capsule
Ingtegrity: Glenoid labrum and glenohumeral ligs.
shoulder abduction: ROM, GH/scapular/humeral rotation?
- ROM: ball and socket joint, shallow glenoid cavity, loos fibrous capsule
- Glenohumeral rotation: deltoid, rotator cuff muscles
- Scapular rotation: trapezius, serr. anterior
- humeral rotation: infraspinatus, teres minor
Proximal and Distal Radio-ulnar joints
Type: synovial pivot
Mvmnts: pronation/supination
muscles: pronator teres and quadratus, supinator and biceps brachii
