upper limb joints Flashcards
gleno-humeral joint
Classification:
Type: synovial
Subtype: ball and socket
Articular surfaces of gleno-humeral joint
Medially: glenoid cavity
Laterally: head of the humerus
Articular surfaces are covered by hyaline cartilage Articular cartilage doesn’t have perichondrium One of the most mobile joints of the body Mobility is at the cost of stability
Anatomically a weak joint
Stabilizing factors of gh joint
Coraco-acromial arch forms the secondary socket Musculotendinous cuff
Glenoidal labrum
Surrounding muscles
Coraco-acromial arch: gh j
Formed by coracoid process, acromion process and coraco-acromial ligament
Musculotendinous cuff (rotator cuff):
Formed by the capsular ligament, supraspinatus, infraspinatus, teres minor and
subscapularis muscles
Glenoidal labrum
Made up of white fibro-cartilage
Deepens the glenoid fossa
Muscles: gh j
Long head of biceps prevents upward displacement of head
Long head of triceps prevents downward displacement of the head
Ligaments of the joint: gh j
Capsular ligament (articular capsule)
- enforced by 3 glenohumeral lig
Coracohumeral ligament- Extends from the root of the coracoid process to the greater tubercle
Transverse humeral ligament- Bridges the gap between greater and lesser tubercles
Glenoidal labrum
Capsular ligament: gh j
Medial attachment:
To the glenoidal labrum
Supraglenoid tubercle is intracapsular
Lateral attachment:
To the anatomical neck of the humerus
Inferiorly it extends up to the surgical neck
Capsule is reinforced by 3 glenohumeral ligaments (superior, middle and inferior)
Capsule and surrounding 4 muscles (subscapularis, supraspinatus, infraspinatus and teres minor) form rotator cuff
Capsule has openings for tendon of long head of biceps and subscapular bursa
Tendon of long head of biceps at gh j
intracapsular but extrasynovial
Relations of shoulder joint:
Anterior:
Anterior fibres of deltoid, short head of biceps and coracobrachialis and subscapularis
Posterior:
Infraspinatus, teres minor and posterior fibres of deltoid
Superior:
Coracoacromial arch, subacromial bursa,deltoid and supraspinatus
Inferior:
Long head of triceps, axillary nerve and posterior circumflex humeral vessels
Blood supply: gh j
Anterior and posterior circumflex humeral vessels
Subscapular vessels
Suprascapular vessels
Nerve supply:
Axillary, musculocutaneous, suprascapular and lateral pectoral nerves
Scapular-humeral mechanism:
-Scapula and upper limb are suspended from the clavicle by coracoclavicular ligament
-Scapula can rotate on the chest wall to change the position of glenoid fossa
- Coracoclavicular ligament forms the axis of rotation of scapula
-180 degrees of abduction is possible
-For every 3 degrees of abduction, 2 degrees occurs at the shoulder joint and one degree by the rotation of scapula
-Scapula is rotated by the combined actions of serratus anterior and trapezius muscles
Applied anatomy: gh j
Dislocations:
-Most commonly dislocated large joint (antero-inferior)
-Axillary nerve can be damaged
Frozen shoulder (adhesive capsulitis):
- pain and loss of motion or stiffness in the shoulder
-in older athletes
-Due to Inflammation of the joint
-Movements are restricted and painful
Rotator cuff tendinitis:
AKA subacromial bursitis, suprspinatus tendinitis or pericapsulitis
Cause: excessive overhead activity
painful abduction
Can lead to rupture of supraspinatus tendon
Elbow joint type
Type: Synovial
Subtype: Hinge
It is a compound and an uniaxial joint
It has humero-radial and humero-ulnar components
The two components and superior radioulnar joint are collectively called ‘cubital articulation’
Articular surfaces: e j
Superiorly: Capitulum and trochelea of humerus
Inferiorly: head of the radius and trochlear notch of ulna
- Articular surfaces are covered by articular cartilage
-Anatomically a strong joint
Ligaments: e j
Capsular ligament
Lateral (radial) collateral ligament
Medial (ulnar) collateral ligament-Anterior ligament,Posterior ligament,transverse ligament
Capsular ligament: e j
Superior attachment:
To the lower end of humerus
Coronoid, raidal and olecranon fossae are intracapsular
Inferior attachment:
To the margin of trochlear notch of ulna and annular ligament
Lateral (radial collateral) ligament:
Triangular, fan shaped
Extends from lateral epicondyle to annular ligament
Gives origin to supinator and extensor carpi radialis brevis muscles
Medial (ulnar collateral) ligament:
Triangular in shape
Apex is attached to the medial epicondyle
Has anterior, posterior and oblique bands
Anterior band is attached to coronoid process Posterior band is attached to olecranon process Related to ulnar nerve
Gives origin to flexor digitorum superficialis muscle
relations e j
Anterior relations:
Brachialis, tendon of biceps, brachial artery and median nerve
Posterior relations:
Triceps and anconeus
Medial relations:
Ulnar nerve, flexor carpi ulnaris and common flexor origin
Lateral relations:
Supinator, extensor carpi radialis brevis, common extensor tendon
Blood supply: e j
Anastomosis around the elbow joint
Nerve supply: ej
Median, radial, ulnar and musculocutaneous nerves
Carrying angle ej
Angle of 170 degrees, between long axis of the arm and forearm
Factors responsible for carrying angle:
1. Medial flange of trochlea is 6mm lower than that of lateral
2. Obliquity of the coronoid process
Applied anatomy: e j
Dislocations: Posterior dislocation is associated with
fracture of coronoid process
Distension:
In backward direction
Capsule is weak posteriorly
Aspiration of fluid can be done by inserting a needle on either side of olecranon
Subluxation (pulled elbow):
-Head of the radius slips out of the grip of annular ligament
-Seen in children
-Happens when the forearm is suddenly pulled in pronation
Tennis elbow:
Abrupt pronation, leading to pain over the lateral epicondyle( lateral epicondylitis)
Causes:
1. Sprain of radial collateral ligament
2. Sprain of extensor carpi radialis brevis
3. Inflammation of bursa deep to the extensor carpi radialis brevis
golfer’s elbow
- medial epicondylitis
Student’s elbow
- Inflamed and enlarged subcutaneous olecranon bursa due to resting of elbow on surface.
Radioulnar joints
Classification:
Superior and inferior radioulnar joints:
Type: Synovial
Subtype: Pivot
Middle (intermediate) radioulnar joint:
Type: Fibrous
Subtype: Syndesmosis
Articular surfaces and lig of superior radioulnar joint:
Head of the radius
Radial notch of ulna and annular ligament
Ligaments:
Capsular ligament, annular ligament, quadrate ligament
Articular surfaces and lig of inferior radioulnar joint:
Articular surfaces of the inferior radioulnar joint:
Head of the ulna
Ulnar notch of the radius
Ligaments:
Capsular ligament
Triangular articular disc
Nerve supply: ru j
Superior radioulnar joint:
Median, radial and musculocutaneous nerves
Inferior radioulnar joint:
Anterior and posterior interosseous nerves
Blood supply: ru j
Superior radioulnar joint:
Anastomosis around the elbow
Inferior radioulnar joint:
Anterior interosseous artery
Muscles ru j
Muscles producing supination:
Biceps brachii, supinator and brachioradialis
Muscles producing pronation:
Pronator teres, pronator quadratus, flexor carpi radialis and brachioradialis
Middle (intermediate) radioulnar joint:
-Between shafts of radius and ulna
Functions of interosseous membrane:
-Binds radius to ulna
-Gives attachment to muscles
-Weight transmission
Wrist Joint (Radiocarpal joint)
Classification:
Type: Synovial
Subtype: Ellipsoid
Articular surfaces: wj
Proximal:
Distal end of radius and articular disc of inferior radioulnar joint
Distal:
Scaphoid, lunate and triquetral bones
Ligaments: wj
Capsular ligament
Anterior (palmar radiocarpal)
Posterior (dorsal radiocarpal
Medial collateral
Lateral collateral
relation wj
Anterior relations:
Long flexor tendons with their synovial sheaths
Median nerve
Posterior relations:
Long extensor tendons with their synovial sheaths
Lateral relation:
Radial artery
muscles + movement
Flexion:
Flexor carpi radialis, flexor carpi ulnaris
Palmaris longus, flexors of fingers
Extension:
Extensor carpi radialis longus Extensor carpi radialis brevis Extensor carpi ulnaris
Long extensors of digits
Adduction:
Flexor carpi ulnaris
Extensor carpi ulnaris
Abduction:
Flexor carpi radialis
Extensor carpi radialis longus Extensor carpi radialis brevis Abductor pollicis longus Extensor pollicis brevis
List and describe some clinical complications with joints
- Sprains
- Damage to cartilage, ligaments due to forceful twisting of joint - Bursitis
- Inflammation of a bursa
- Overuse of a joint - Arthritis
- Inflamed, swollen, painful joints
- Osteoarthritis
- Gout - Dislocation of joint
- Articular surfaces of joint are abnormally displaced - Subluxation:
- Partial contact is still remained - Neuropathic joint
- Sensation is completely lost, prone to mechanical damage
Describe and draw the Synovial Joint
Structure:
- Articulating ends of the bones taking part in the synovial joints are enclosed in a fibrous capsule.
- The articular surfaces of the bones are lined by articular cartilage.
- The articular cartilage is a thin layer of hyaline cartilage covering the epiphysis where bone takes part in a joint.
- Articular cartilage has no perichondrium (lacks nerve supply and capacity to regenerate), the only nutritional source is the synovial fluid.
- Degeneration of the articular cartilage as age advances is the root cause of osteoarthritis. - Internal surface of fibrous capsule and the non-articular parts of articulating bones inside the joint cavity are lined by synovial membrane.
- The joint cavity is filled with synovial fluid (secreted by synovial membrane). This synovial fluid is a lubricant and provides nutrition to articular cartilages.
- In some joints, the fibrocartilaginous articular discs may be present and the fibrous capsule is strengthened by ligaments (true, and accessory)
Altogether, the synovial joints allow for free movements.
