Radius Flashcards
What is the radius?
A long bone in the forearm
Where does the radius lie?
Laterally and parallel to the ulna
What does the radius do?
Pivots around the ulna at the proximal and distal radio-ulnar joint
Where does the radius articulate?
Elbow joint
Proximal radioulnar joint
Wrist joint
Distal radioulnar joint
What is the elbow joint formed by?
Partly, an articulation between the head of the radius and the capitulum of the humerus
What forms the proximal radioulnar joint?
An articulation between the radial head and the radial notch of the ulna
What forms the wrist joint?
An articulation between the distal end of the radius and the carpal bones
What forms the distal radioulnar joint?
An articulation between the ulnar notch and the head of the ulna
Where does proximal end of the radius articulate?
In the elbow and proximal radioulnar joints
What are the important landmarks of the proximal region of the radius?
Head
Neck
Radial tuberosity
What shape is the head of the radius?
Disk shaped, with a concave articulating surface.
Thicker medially
What does the head of the radius take part in?
The proximal radioulnar joint
What is the neck of the radius?
A narrow area of bone
Where does the neck of the radius lie?
The radial head and radial tuberosity
What is the radial tuberosity?
A bony projection
What does the radial tuberosity serve as?
The place of attachment of the biceps brachii muscle
What happens to the radial shaft as it moves distally?
It expands in diameter
What shape is the shaft of the radius?
Triangular
What does the shaft of the radius have?
Three borders and three surfaces
What is in the middle of the lateral surface of the radial shaft?
A small roughening for the attachment of the pronator teres muscle
What happens to the radius in the distal region?
It expands to form a rectangular end
What happens to the lateral side of the distal region of the radius?
It projects distally as the styloid process
What is in the medial surface of the distal region of the radius?
A concavity called the ulnar notch
What does the ulnar notch do?
Articulates with the head of the ulna
What is formed when the ulnar notch articulates with the head of the ulna?
The distal radioulnar joint
What does the distal surface of the radius have?
Two facets for articulation with the scaphoid and lunate carpal bones
What is formed with the articulation of the radius and carpal bones?
The wrist joint
What are the common fracture types involving the radius?
Colles’ fracture
Fractures of the radial head
Smith’s Fracture
What is the most common type of radial fracture?
Colles’ fracture
What causes Colles’ fracture?
A fall onto an outstretched hand
What happens in a Colles’ fracture?
A fracture of the distal radius The structures distal to the fracture (wrist and hand) are displaced posteriorly
What does a Colles’ fracture produce?
A ‘dinner fork’ deformity
What are fractures of the radial head characteristically due to?
Falling on an outstretched hand
What happens in fractures to the radial head?
The radial head is forced into the capitulum of the humerus, causing it to fracture
What causes a Smith’s fracture?
Falling onto the back of the hand
What happens in Smith’s fracture?
The distal fragment is now placed anteriorly
