Ioints Of The Upper Limb Flashcards
Elevation
Initial 30 degrees may occur without scapular motion
2:1 ratio
Every 3 degrees of movement, 2 degrees at glenohumeral joint and 1 degree at scapulothoracic joint
Scapulohumeral rhythm
Movement of pectoral girdle
Sternoclavicular, acromioclavicular and glenohumeral joints
Sternoclavicular joint general
Synovial articulation between Sternal end of the clavicle and the manubrium of the sternum and the first costal cartilage
Saddle type of joint but functions as a ball and socket joint
Sternoclavicular joint divisions
Divided into two compartments by an articular disc
Disc attached to anterior and posterior SC ligaments and the inter clavicular ligament
Serves as a shock absorber of forces transmitted along clavicle from upper limb
Fracture of clavicle more common than dislocation
Joint capsule of SC joint
Surrounds joint, including epiphysis at Sternal end of clavicle
Fibrous layer of capsule attached to margins of articular surfaces
Synovial membrane lines internal surfaces of fibrous layer
Ligaments of SC joint
Anterior and posterior SC ligaments reinforce capsule anteriorly and posteriorly
Inter clavicular ligament strengthens capsule superiorly. From Sternal end of one clavicle to Sternal end of the other, also attached to superior border of manubrium
Costoclavicular ligament anchors inferior surface of Sternal end of clavicle to the 1st rib and it’s costal cartilage,limiting elevation of the pectoral girdle
Movement of SC joint
Very strong but significantly mobile
During full elevation if limb, clavicle is raised to approximately 60 degree angle
Can also be moved anteriorly or posteriorly over a range up to 25 to 30 degrees
Blood and nervous supply to SC joint
Internal thoracic and suprascapular arteries
Branches of medial supra clavicular nerve and subclavian nerve supply SC joint
Acromioclavicular joint general
Plane synovial articulation
2 to 3 cm from the point of the shoulder, formed by the lateral part of the acromion of the scapula
The acromial end of the clavicle articulates with the acromion
The articular surfaces, covered with fibrocartilage are separated by an incomplete wedge shaped articular disc
Joint capsule of AC joint
Sleeve like, relatively loose fibrous layer is attached to margins of articular surfaces
Synovial membrane lines internal surface of fibrous layer of the capsule
Relatively weak but strengthened superiorly by fibers of the trapezius
Ligaments of AC joint
AC ligament
Coracoclavicular ligament: conoid and trapezoid
AC ligament
AC ligament: fibrous band from acromion to clavicle: strengthens AC joint superiorly
Coracoclavicular ligament
Coracoclavicular ligament: gives most of strength: prevent acromion from being driven under clavicle even when joint is separated: extra articular, strong, subdivided into conoid and trapezoid ligaments, located several centimeters from joint, clavicle to coracoacromial process of scapula. Provides means by which scapula and free limb are suspended from clavicle
Conoid: vertical: apex attached to root of coracoid process, base is to conoid tubercle on inferior surface of clavicle
Trapezoid: nearly horizontal: attached to superior surface of coracoid process and extends laterally to trapezoid line on the inferior surface of the clavicle
AC joint blood and nervous supply
Suprascapular and thoraco-acromial arteries
Supra clavicular lateral pectoral and axillary nerves
Glenohumeral joint general
Ball and socket synovial joint
High mobility, low stability
Large spherical humeral head articulates with relatively small and shallow glenoid cavity which is deepened slightly by ring like, fibrocartiliginous glenoid labrum
Both articular surfaces: hyaline cartilage
Glenoid cavity accepts about 1/3 of humeral head, which is held in cavity by Rotator cuff
Glenohumeral joint joint capsule
Loose fibrous layer surrounds glenohumeral joint and is attached medially to margin of glenoid cavity and laterally to anatomical neck of the humerus. Superiorly encloses proximal attachment of long head of biceps to supra glenoid tubercle
Inferior part of capsule not reinforced by rotator cuff: weakest: lies in folds when arm adducted: becomes taut when abducted
Synovial membrane lines internal surface and reflects onto humerus as far as articular margin of head. Also forms tubular sheath for tendon of long head of biceps brachii
Anteriorly, Communication between subscapular bursa and synovial cavity of joint
Ligaments of glenohumeral joint
Glenohumeral, coracohumeral, transverse humeral ligaments, coraco-acromial arch, coraco-acromial ligament
Glenohumeral ligaments
Evident only on internal aspect of glenohumeral joint capsule
Strengthen anterior aspect of capusle
Coracohumeral ligament
Strong band that passes from base of coracoid process to anterior aspect of greater tubercle, strengthens glenohumeral capsule superiorly
Transverse humeral ligament
Broad fibrous band that runs from greater to lesser tubercle, bridging over the intertubercular sulcus and converting the sulcus into a canal for the tendon of the long head of biceps brachii and it’s synovial sheath
Coraco-acromial arch
Extrinsic, protective structure formed by smooth inferior aspect of acromion and coracoid process of the scapula, with coraco- acromial ligament spanning between them
Overlies head of humerus, preventing its superior displacement from glenoid cavity
So strong that forceful superior thrust of humerus will fracture shaft of humerus or clavicle first
Blood supply and innervation of glenohumeral joint
Anterior and posterior circumflex humeral arteries and branches of suprascapular artery
Suprascapular, axillary and lateral pectoral nerves supply joint
Bursae around glenohumeral joint
Subacromial or sub deltoid bursa and subscapular bursa
Subacromial or sub deltoid bursa
between acromion, coracoacromial ligament, and deltoid superiorly, and supraspinatus tendon and joint capsule of glenohumeral joint inferiorly. Facilitates movement of supraspinatus tendon under coracoacromial arch and of deltoid over joint capsule and greater tubercle of humerus
Subscapular bursa
Between tendon of subscapularis and neck of scapula
Protects tendon where it passes inferior to root of coracoid process and over neck of scapula
Usually communicates with cavity of glenohumeral joint through an opening in the fibrous layer of joint capsule
Rotator cuff injuries
Usually repetitive use of upper limb above the horizontal
Tendinitis of rotator cuff, usually supraspinatus tendon
Cannot initiate abduction if upper limb
If passively abducted 15 degrees or more, deltoid takes over
Dislocation of acromioclavicular joint
Easily injured by direct blow, fall on shoulder or outstretched limb
Shoulder separation
Severe when both AC and coraco clavicular ligaments are torn
When coraco clavicular ligament tears, shoulder separates from clavicle and falls because of weight of limb
Makes acromion more prominent and clavicle may move superior to acromion
Dislocation of glenohumeral joint
Most in inferior direction but described as anterior or (more rare) posterior
Anterior: more often in young adults: excessive extension and lateral rotation, head of humerus driven infero anteriorly
Axillary nerve may be injured
Capsule torn
Strong adductors and flexors may pull into sub coracoid position
Calcific supraspinatus tendinitis
Males 50 and up after unusual or excessive use of glenohumeral joint
Calcific scapulohumeral bursitis
Calcium deposits in supraspinatus tendon irritate subacromial bursa
No pain in adduction
Pain in 50-130 degrees of abduction
Adhesive capsulits of glenohumeral joint
Frozen shoulder
Caused by adhesive fibrosis and scarring between inflamed capsule of glenohumeral joint, rotator cuff, subacromial bursa and deltoid
Difficulty abducting arm but can obtain apparent abduction of 45 degrees by elevating and rotating scapula
Initiated by glenohumeral dislocations, Calcific supraspinatus tendinitis, partial tearing of rotator cuff, bicipital tendinitis
Movements of glenohumeral joint
Flexion extension
Abduction, adduction
Rotation
Circumduction
Things affecting movement at glenohumeral
Lateral rotation increases range of abduction
When arm is abducted without rotation, greater tubercle contacts coracoacromial arch preventing further abduction
If Arm is then laterally rotated 180 degrees, tubercles are rotated posteriorly and more articular surface becomes available to continue elevation
Stiffening or fixation of joints of pectoral girdle (ankylosis) results in a much more restricted range of movement
elbow joint general
hinge type of synovial joint
located 2 to 3 cm inferior to the humeral epicondyles
spool shaped trochlea and spheroidal capitulum of the humerus articulate with the trochlear notch of the ulna and the slightly concave superior aspect of head of radius, respectively
articulation and joint capsule of elbow joint
fibrous layer of joint capsule surrounding joint is attached to humerus at margins of lateral and medial ends of articular surfaces of capitulum and trochlea
anteriorly and posteriorly, it is carried superiorly, proximal to the coronoid and olecranon fossae
synovial membrane lines internal surface of fibrous layer of joint capsule and intracapsular nonarticular parts of humerus. continuous inferiorly with synovial membrane of proximal radio ulnar joint
ligaments of elbow joint
collateral ligaments of elbow joint: strong triangular bands that are medial and lateral thickenings of fibrous layer of the joint capsule
radial collateral ligament, anular ligament of radius, ulnar collateral ligament
radial collateral ligament
: lateral, fan like, extends from the lateral epicondyle of humerus and blends distally with anular ligament of radius:
anular ligament of radius
encircles and hold head of radius in radial notch of the ulna, forming proximal radio-ulnar joint and permitting pronation and supination of forearm
ulnar collateral ligament
medial, triangular, extends from medial epicondyle of humerus to coronoid process and olecranon of ulna
three bands:
1. anterior cord like band: strongest
2. posterior fan like band: weakest
3. slender oblique band: deepens socket for trochlea of humerus
movements of elbow joint
flexion and extension
long axis of fully extended ulna makes 170 degree angle with long axis of humerus: carrying angle
obliquity of angle is more pronounced in women than in men
blood supply and innervation of elbow joint
arteries derived from anastomosis of arteries around elbow joint
supplied by musculocutaneous, radial and ulnar nerves
bursae around elbow joint
intratendinous olecranon bursa: sometimes present in tendon of triceps brachii
subtendinous olecranon bursa: located between olecranon and triceps tendon, just proximal to its attachment to the olecranon
subcutaneous olecranon bursa: located in subcutaneous connective tissue over olecrana
bicipitoradial bursa
or biceps bursa
separates biceps tendon from anterior part of radial tuberosity
proximal radio-ulnar joint general
pivot type of synovial joint that allows movement of the head of the radius on the ulna
articulation and joint capsule of proximal radio-ulnar joint
head of radius articulates with radial notch of ulna
fibrous layer of joint capsule encloses joint and is continous with that of elbow joint
synovial membrane lines internal surface of fibrous layer and nonarticulating aspects of bones
synovial membrane is inferior prolongation of synovial membrane of elbow joint
ligaments of proximal radio ulnar joint
anular ligament: attaches to ulna, anterior and posterior to radial notch, which forms a collar that, with the radial notch, forms a ring that completely encircles the head of the radius. deep surface lined with synovial membrane which continues distally as a sacciform recess of the proximal radio-ulnar joint on the neck of the radius
arrangement allows radius to rotate within anular ligament without binding, stretching or tearing synovial membrane
elbow extension joints
humero-ulnar
humeroradial
elbow extension limiting structures
musces: flexor muscles of elbow
joint capsule: anteriorly
bony apposition: between olecranon of ulna and olecranon fossa of humerus
elbow flexion joints
humero-ulnar
humeroradial
elbow flexion limiting structures
muscle: triceps brachii
joint capsule: posteriorly
soft tissue:apposition between anterior forearm and arm
bony apposition: between head of radius and radial fossa of humerus
elbow pronation joints
humeroradial, proximal radio-ulnar, distalradio-ulnar, interosseus membrane
elbow pronation limiting structures
muscles:supinator, biceps brachii
ligaments: dorsal inferior radio-ulnar, interosseus membrane
bony apposition of radius on ulna
elbow supination joints
humeroradial
proximal radio ulnar
distal radio ulnar
elbow supination limiting structures
muscles: pronator teres, pronator quadratus
ligaments: anterior inferior radio ulnar, interosseus membrane
distal radio ulnar joint general
pivot type of synovial joint
radius moves around the relatively flexed distal end of the ulna
articulation and joint capsule of distal radio-ulnar joint
fibrocartiliginous articular disc of the distal radio-ulnar joint binds theend of the ulna and radius together. base of disc attaches the medial edge of ulnar notch of radius, and apex is attached to the lateral side of the base of styloid process of ulna
proximal surface of this triangular disc articulates with the distal aspect of the head of the ulna.
sacciform recess of distal radioulnar joint is extension of synovial membrane
ligaments of distal radio-ulnar joint
anterior and posterior ligaments strengthen the fibrous layer of joint capsule. relatively weak
movements of proximal and distal radio-ulnar joints
pronation and supination: head of radius rotates within the cup shaped anular ligament and the distal end of the radius rotates around the head of the ulna
arteries and nerves of proximal and distal radio-ulnar joints
proximal: supplied by radial portion of peri-articular arterial anastomosis of elbow joint. innervated by musculocutaneous, median and radial nerves
distal: anterior and posterior interosseous arteries and nerves
pronation: median nerve
supination: musculocutaneous and radial
bursitis of elbow
subcutaneous olecranon bursitis: students elbow
excessive friction between triceps tendon and olecranon
pain severe during flexion of forearm because of pressure exerted on inflamed subtendinous olecranon bursa by triceps tendon
avulsion of medial epicondyle
in children, can result from a fall that causes severe abduction of external elbow
traction on ulnar collateral ligament pulls medial epicondyle distally
traction injury of the ulnar nerve is a complication of the abduction type of avulsion of the medial epicondyle
ulnar collateral ligament reconstruction
rupture, tearing and stretching more common because of throwing
reconstruction: “Tommy John procedure” : transplant of a long tendon from contralateral forearm or leg
dislocation of elbow joint
posterior dislocaion may occur when children fall on their hands with their elbow flexed
subluxation and dislocation of radial head
nurse maids elbow
dislocation of head of radius, tear of anular ligament
