cubital fossa and elbow joint.pptx

CUBITAL FOSSA AND ELBOW JOINT Dr. Amtul Sughra CUBITAL FOSSA  The Cubital fossa is a triangular-shaped depression over the anterior aspect of the elbow joint.  It represents an area of transition between the anatomical arm and the forearm, and conveys several i...

CUBITAL FOSSA AND ELBOW JOINT Dr. Amtul Sughra CUBITAL FOSSA  The Cubital fossa is a triangular-shaped depression over the anterior aspect of the elbow joint.  It represents an area of transition between the anatomical arm and the forearm, and conveys several important structures between these two areas.  CUBITAL FOSSA The cubital fossa is consist of three borders, a roof, and a floor: Lateral border medial border of the brachioradialis muscle. Medial border – lateral border of the pronator teres muscle. Superior base: Line between two humeral epicondyles.  Cubital Fossa Boundaries  Roof: Skin, superficial fascia and deep fascia and bicipital aponeurosis.  Floor: Supinator and brachialis muscles.  APEX: directed downwards, formed by meeting of lateral and medial boundaries.  The roof of the cubital fossa also contains several superficial veins.  Notably, the median cubital vein, which connects the basilic and cephalic veins and can be accessed easily – a common site for venipuncture.  Cubital Fossa Contents The cubital fossa is a passageway for structures to pass between the upper arm and forearm. Its contents are (lateral to medial): 1. Radial nerve – travels along the lateral border of the cubital fossa and divides into superficial and deep branches. It has a motor and sensory function in the posterior forearm and hand. 2. Biceps tendon – passes centrally through the cubital fossa and attaches the radial tuberosity (immediately distal to the radial neck). It gives rise to the bicipital aponeurosis which contributes to the roof of the cubital fossa. 3. Brachial artery – bifurcates into the radial and ulnar arteries at the apex of the cubital fossa. The brachial pulse can be felt in the cubital fossa by palpating medial to the biceps tendon 4. Median nerve – travels medially through the cubital fossa, exiting by passing between the two heads of the pronator teres. It has a motor and sensory function in the anterior forearm and hand. Cubital Fossa Contents  Clinical applications Venipuncture The cubital fossa is a common site for sampling and transfusion of blood, and intravenous injections because of the prominence and accessibility of the 'attending' veins. The median cubital vein is most commonly accessed for venipuncture. The median cubital vein is also a site for the introduction of cardiac catheters to secure blood samples from the great vessels and chambers of the heart. This route may also be used for coronary angiography. Blood pressure measurements The cubital fossa is a site for placement of the diaphragm of the stethoscope during blood pressure measurement to palpate the pulse of the brachial artery.  Supracondylar Fracture A supracondylar fracture is a fracture of the distal humerus. The fracture is typically transverse or oblique, and the most common mechanism of injury is falling on an outstretched hand. It is more common in children than adults. In this type of injury, the contents of the cubital fossa can be damaged – either directly, or by soft tissue swelling following the trauma. Damage to the brachial artery, if not repaired, can cause Volkmann’s ischaemic contracture (uncontrolled flexion of the hand) as the forearm flexor muscles become fibrotic and short. ELBOW JOINT  Elbow Anatomy  The elbow is the joint connecting the upper arm to the forearm. It is classed as a hinge-type synovial joint.  Elbow joint is made of  3 bones  2 joints  One capsule  Hinge joint  Flexion and extension  ELBOW JOINT  The elbow joint is hinge variety of synovial joint between lower end of humerus and upper ends of radius and ulna.  Articulating surfaces:  UPPER: capitulum and trochlea of humerus.  LOWER: upper surface of head of radius articulates with capitulum and trochlear notch of ulna articulates with trochlea of humerus.  Elbow joint articulates with superior radioulnar joint.  Joint Capsule and Bursae The elbow joint has a capsule enclosing the joint. This in itself is strong and fibrous, strengthening the joint. The joint capsule is thickened medially and laterally to form collateral ligaments, which stabilize the flexing and extending motion of the arm. A bursa is a membranous sac filled with synovial fluid. It acts as a cushion to reduce friction between the moving parts of a joint, limiting degenerative damage.  ELBOW JOINT Intratendinous olecranon – located within the tendon of the triceps brachii. Subtendinous onlecranon – between the olecranon and the tendon of the triceps brachii, reducing friction between the two structures during extension and flexion of the arm. Subcutaneous olecranon bursa – between the olecranon and the overlying connective tissue (implicated in olecranon bursitis).  LIGAMENTS: 1. Ulnar collateral ligament (medial). 2. Radial collateral ligament (lateral). 3. Annular ligament The radial collateral ligament is found on the lateral side of the joint, extending from the lateral epicondyle, and blending with the annular ligament of the radius (a ligament from the proximal radioulnar joint). The ulnar collateral ligament originates from the medial epicondyle, and attaches to the coronoid process and olecranon of the ulna.  ELBOW JOINT  BLOOD SUPPLY: from anastomosis around elbow joint. which is formed by branches of the brachial artery.  NERVE SUPPLY: branches from; 1. Ulnar nerve. 2. Median nerve. 3. Radial nerve. 4. Musculocutaneous nerve.  MOVEMENTS  FLEXION by anterior compartment muscles. (brachialis, biceps brachii, brachioradialis)  EXTENSION by posterior compartment muscles. – (triceps brachii and anconeus)  Clinical Relevance: Injuries to the Elbow Joint  Bursitis  Subcutaneous bursitis: Repeated friction and pressure on the bursa can cause it to become inflamed. Because this bursa lies relatively superficially, it can also become infected (e.g cut from a fall on the elbow)  Subtendinous bursitis: This is caused by repeated flexion and extension of the forearm, commonly seen in assembly line workers. Usually flexion is more painful as more pressure is put on the bursa.  Dislocation  An elbow dislocation usually occurs when a young child falls on a hand with the elbow flexed. The distal end of the humerus is driven through the weakest part of the joint capsule, which is the anterior side. The ulnar collateral ligament is usually torn and there can also be ulnar nerve involvement  Most elbow dislocations are posterior, and it is important to note that elbow dislocations are named by the position of the ulna and radius, not the humerus.  Epicondylitis (Tennis elbow or Golfer’s elbow)  Most of the flexor and extensor muscles in the forearm have a common tendinous origin.  The flexor muscles originate from the medial epicondyle, and the extensor muscles from the lateral epicondyle.  Sportspersons can develop an overuse strain of the common tendon – which results in pain and inflammation around the area of the affected epicondyle.  Typically, tennis players experience pain in the lateral epicondyle from the common extensor origin.  Golfers experience pain in the medial epicondyle from the common flexor origin.  This is easily remembered as golfers aim for the ‘middle’ of the fairway, while tennis players aim for the ‘lateral’ line of the court!  Supracondylar Fracture A supracondylar fracture is a fracture of the distal humerus. The fracture is typically transverse or oblique, and the most common mechanism of injury is falling on an outstretched hand. It is more common in children than adults. In this type of injury, the contents of the cubital fossa can be damaged – either directly, or by soft tissue swelling following the trauma. Damage to the brachial artery, if not repaired, can cause Volkmann’s ischaemic contracture (uncontrolled flexion of the hand) as the forearm flexor muscles become fibrotic and short. THANK YOU…