5 - Elbow, Wrist Flashcards
What are the articulations of the elbow joint?
Humerus, Ulna and RadiusHumerus- Trochlea- Capitulum- Olecrannon Fossa- Coronoid Fossa- Radial FossaUlna - Coronoid process- Trochlear notch- Olecrannon processRadius - Head
What type of joint is the elbow joint?
Hinge type synovial joint
What happens at full extension of elbow?
Ulna makes an angle of 170* with the humerus
What muscles produce the flexing hinge movemet of the elbow?What muscle extend the elbow?
Flexion: Brachialis, Biceps brachii, BrachioradialisExtension: Triceps brachii and Aconeus
Describe the capsule of the elbow
- Weak anteriorly and posterioly- Strengthened by collateral ligaments medially and laterally- Capsule of the elbow shares with proximal radioulnar joint
What are the two collateral ligaments which strengthen the elbow?
The ulna collateral ligament The radial collateral ligament
What is the ulna collateral ligament made up of?
Three bands - Anterior, Posterior and Oblique (deepens socket for trochlea)
Describe the radial collateral ligament of the elbow
Fan like, blends with annular ligament
What lies underneath the fibrous capsule of the elbow joint?
Synovial membrane lines the fibrous capsule and humerus
Label the diagram - What are A, B and C?
A - Radial collateral ligament B 0 Ulnar collateral ligament C - Annular ligament of radius
What is the function of elbow bursae?
act to cushion the moving parts of a joint, preventing degenerative damage
What are three important bursae of the elbow?
Intratendinosus - Formed within the tendon of the triceps brachiiSubtendinosus - Found between the olecrannon and tedon of the triceps brachii, reducing friction during extension and flexionSubcutaneous - Found between olecrannon and overlying connective tissue
What is subcutaneous bursitis of the elbow?
Repeated friction and pressure on the bursa can cause it become inflamed. Because this bursa lies relatively superficially, it can also become infected (e.g cut from a fall on the elbow), and this would also cause inflammation
What is 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.
What nerves are significant in elbow joint?
Radial nervepasses anterior tolateral epicondyle
What are the three parts of the radioulnar joints?
Proximal Radioulnar jointInterosseous membraneDistal radio ulnar
What is the proximal radioulnar joint formed by?
the head of the radius articulating with the radial notch of the ulna
What is the head of the radius held in place by?
The annular ligament of the radius
What prevents friction during movement of the proximal radioulnar joint?
The anular radial ligament is lined with a synovial membrane
What is movement produced by in the proximal radioulnar joint?
the head of the radius rotating within the anular ligament on the capitulum of the humerus
What are the two movements possible at the proximal radioulnar head, and how?
Pronation: Produced by the pronator quadratus and pronator teresSupination: Produced by the supinator and biceps brachii
What is Hilton’s law?
The principle that the nerve supplying a joint also supplies both the muscles that move the joint and the skin covering the articular insertion of those muscles.
What is the interosseous membrane of the radioulna joint?
Fibrous joint which allows distribution of force from radius to ulna
What does the distal radioulna joint consist of?
The head of the ulnar and the ulnar notch on the side of the radius.
What strengthens the distal radioulna joint?
- Anterior and posterior ligaments - Fibrocartilaginous ligament called articular disk
What are the two roles of the articular disk at the distal radioulna joint?
- Binds the radius and ulna together, and holds them together during movement at the joint- Separates the distal radioulnar joint from the wrist joint
What type of joints are the proximal and distal radioulna joints?
Pivot
What two movements is the distal radioulna joint capable of?
Pronation: Produced by the pronator quadratus and pronator teresSupination: Produced by the supinator and biceps brachii
What occurs during pronation and supination of the distal radioulna joint?
he ulnar notch of the radius slides anteriorly over the head of the ulnar during such movements.
What is the name for the structure which allows twisting of the synovial capsula at the distal radioulna joint?
Sacciform recess
What is the wrist joint formed from?
The wrist joint is formed by the articulation of distal end of the radius, the articular disk and the proximal row of the carpal bones (except the pisiform).
What prevents the ulna interacting with the wrist joint?
Prevented by articular disk
What type of joint is the wrist joint?
Synovial, condyloid joint
What three things contribbute to stability of wrist joint?
The joint capsule, structure of the joint and the associated ligaments
How does the joint capsule contribute to stability?
The fibrous outer layer attaches to the radius, ulna and the proximal row of the carpal bones. The internal layer is comprised of a synovial membrane, secreting synovial fluid, lubricating the joint
How does the structure of the wrist joint contribute to stabiity?
Excessive abduction of the wrist is prevented by the radial styloid process.
Name four ligaments of the wrist
Palmar radiocarpalDorsal radiocarpal Ulnar collateralRadial collateral
What is the function of the palmar radiocarpal ligament, other than stability
ensure that the hand follows the forearm during supination
What is the function of the dorsal radiocarpal ligament, other than stability
ensures that the hand follows the forearm during pronation
What movements is the wrist joint capapble of?
flexion, extension, adduction and abduction
What muscles contribute to flexion of the wrist?
Flexor Carpi UlnarisFlexor Carpi RadialisFlexor Digitorum SuperficialisFlexor Digitorum ProfundusPalmaris Longus
What muscles contribute to extension of the wrist?
Extensore Carpi Radialis longusExtensor Carpi radialis brevisExtensor carpi ulnarisExtensor digitorumExtensor pollicis longusextensor indices
What muscles contribute to adduction of the wrist?
Extensor carpi ulnaris and Flexor carpi ulnaris
What muscles contribute to abduction of the wrist?
Abductor pollicis longus, Flexor carpi radialis, Extensor carpi radialis longus and brevis.
What is the vascular supply of the elbow?
Arterial anastamoses formed by collateral arteries and recurrent branches of ulnar, radial and interosseous arteries
