The Elbow Joint

Question 1

What type of joint is the elbow joint?

Answer 1

Structurally it’s classed as a synovial joint

Functionally it’s classed as a hinge joint

Question 2

Name the articulating surfaces of the elbow joint

Answer 2

There are two separate articulations:

• Trochlear notch of the ulna and the trochlea of the humerus
• Head of the radius and capitulum of the humerus

Question 3

Where is the proximal radioulnar joint found?

Answer 3

It’s found within the same joint capsule of the elbow

Question 4

Outline the stability of the elbow joint

Answer 4

Like all synovial joints, the elbow 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 stabilise the flexing and extending motion of the arm.

Question 5

Describe the radial collateral ligament

Answer 5

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)

Question 6

Describe the ulnar collateral ligament

Answer 6

Originates from the medial epicondyle and attaches to the coronoid process and olecranon of the ulna

Question 7

Describe the Bursae of the elbow joint

Answer 7

A bursa is a membranous sac filled with synovial fluid. It acts to cushion the moving parts of a joint, preventing degenerative damage. There are many bursae in the elbow, but only a few have clinical importance:
Intratendinous - located within the tendon of the triceps brachii
Subtendinous - between the olecranon and the tendon of the triceps brachii, reducing friction between the two structures during extension and flexion of the arm
Subcutaneous - between the olecranon and the overlying connective tissue