MSK - Elbow Joint and Wrist Flashcards
What are the three major ligaments associated with the elbow joint?
Describe their origins and insertions.
What are their functions?
Radial collateral ligament - fan like, attaches between the lateral epicondyle of the humerus and annular ligament of the radius below. It keeps the head of the radius and capitulum in close association.
Ulnar collateral ligament - triangular, attaches to the medial epicondyle of the humerus and the Coronoid process and olecranon of the ulnar. It consists of three bands, the strong anterior band, fan like weak posterior band and slender oblique band which deepens the socket for the trochlear of the humerus
Annular ligament - surrounds the lower part of the head of the radius and maintains its contact with the radial notch of the ulnar
What is the origin and insertion for the radial collateral ligament?
What is its function?
Fan like, attaches between the lateral epicondyle of the humerus and annular ligament of the radius below.
It keeps the head of the radius and capitulum in close association.
What is the origin and insertion for the ulnar collateral ligament?
What is its function?
Triangular, attaches to the medial epicondyle of the humerus and the Coronoid process and olecranon of the ulnar.
It consists of three bands, the strong anterior band, fan like weak posterior band and slender oblique band which deepens the socket for the trochlear of the humerus
What is the origin and insertion for the annular ligament?
Surrounds the lower part of the head of the radius and maintains its contact with the radial notch of the ulnar
What are the main flexors of the elbow?
What muscles produce extension of the elbow?
Brachialis
Biceps brachii
Brachioradialis
Triceps and anconeus
Where does supination and pronation occur?
What muscles is supination produced by?
When do these muscles NOT act together?
Proximal radioulnar joint
Supinator and biceps brachii
Always act together except when the elbow joint is fully extended
In what joint does pronation occur?
What muscles produce pronation?
Proximal radioulnar joint
Pronator quadrus and pronator teres
What are the names of the two important bursae around the elbow joint?
Why can they become inflamed?
When is pain most severe?
Subcutaenous olecranon bursa - lies in the subcutaenous connective tissue overlying the olecranon. Inflammation - Repeated pressure and friction
Subtendious bursa - lies between the triceps tendon and the olecranon. Inflammation due to repeated flexion and extension in the elbow e.g. Assembly line workers.
During flexion of the forearm - pressure exerted on the inflamed subtendinous olecranon bursa by triceps tendon
What may become inflamed during repeated pronation/supination movements?
A bursa between the biceps tendon and the radius
What may dislocate when attempting to life a child or swing a child by the hands when the arm is fully abducted?
Dislocation of the radial head
When can avulsion of the medial epicondyle occur?
How does it occur?
After a fall which causes severe abduction of the fully extended forearm.
Traction on the ulnar collateral ligaments pulls the medial epicondyle medially.
What may cause a posterior dislocation?
A fall on the flexed elbow
What type of joint is the distal radioulnar joint?
What muscles are involved in moving it?
Pivot joint - in which the distal end of the radius moves around the distal end of the ulnar
Supinator and biceps brachii
What does the interosessous membrane do?
Where is it attached?
Form a fibrous joint between the radius and ulnar
From the radius proximally to the ulnar distally
The membrane keeps the bones in close apposition during the movements of supination and pronation and prevents proximal displacement of the radius if a force is applied to the outstretched hand
What type of joint is the wrist/radiocarpal joint?
Where is it formed between?
What ligaments stabilise it?
Condyloid type of synovial joint
Between the distal end of the radius and the scaphoid, lunate, triquetrum
