2.4. The Radio-Ulnar Joint Flashcards
What are the Radio-Ulnar Joints?
Locations at which the Radius and the Ulna unite in the Forearm
How many Radio-Ulnar Joints are there?
2
What are the names of the 2 Radio-Ulnar Joints?
- Proximal Radio-Ulnar Joint
2. Distal Radio-Ulnar Joint
Where is the Proximal Radio-Ulnar Joint located?
Immediately Distal to the Elbow Joint
What are the Articulating Surfaces in the Proximal Radio-Ulnar Joint?
- Radial Head
2. Radial Notch of the Ulna
What Type of Joint is the Proximal Radio-Ulnar Joint?
Synovial Pivot
What Encloses the Proximal Radio-Ulnar Joint?
The same Joint Capsule as the Elbow Joint
What holds the Radial Head in place?
The Radial Annular Ligament
How is the Radial Annular Ligament described?
As a “Collar” around the Joint
What lines the Radial Annular Ligament?
A Synovial Membrane
What is the purpose of the Synovial Membrane which lines the Radial Annular Ligament?
To reduce friction during movement
How is movement produced at the Proximal Radio-Ulnar Joint?
The Radial Head rotating inside the Radial Annular Ligament
What movements can occur at the Proximal Radio-Ulnar Joint?
- Pronation
2. Supination
Where is the Distal Radio-Ulnar Joint located?
Immediately Proximal to the Wrist Joint
What are the Articulating Surfaces in the Distal Radio-Ulnar Joint?
- Ulnar Notch of the Radius
2. Ulnar Head
What Type of Joint is the Distal Radio-Ulnar Joint?
Synovial Pivot
What Ligaments strengthen the Distal Radio-Ulnar Joint?
- Anterior Ligament
- Posterior Ligament
- Fibrocartilaginous Ligament
What is the Fibrocartilaginous Ligament also known as?
Articular Disk
What are the functions of the Articular Disk?
- Binds the Radius and the Ulna together (holds them together during movement)
- Separates the Distal Radio-Ulnar Joint from the Wrist Joint
What movements can occur at the Distal Radio-Ulnar Joint?
- Pronation
2. Supination
How is movement produced at the Distal Radio-Ulnar Joint?
The Ulna Notch of the Radius slides Anteriorly over the Ulnar Head
What are the main Muscles producing Pronation?
- Pronator Quadratus
2. Pronator Teres
What are the main Muscles producing Supination?
- Supinator
2. Biceps Brachii
What Accessory Muscles produce Pronation?
- Flexor Carpi Radialis
- Palmaris Longus
- Brachioradialis