Radioulnar Joints

Question 1

Proximal radioulnar joint

Answer 1

Near elbow
Articulation between head of radius and radial notch of ulna
Enclosed in elbow joint capsule
Radial head held by annular radial ligament

Question 2

Distal radioulnar joint

Answer 2

Near wrist
Articulation between ulnar notch of radius and head of ulna
Anterior/posterior ligaments strengthen
Articular disc - binds radius and ulna together, separates distal radioulnar joint from wrist joint

Question 3

Movements

Answer 3

Pronation - pronator quadratus, pronator teres

Supination - supinator, biceps brachii

Question 4

Interosseous membrane

Answer 4

Sheet of connective tissue joins radius and ulna
Spans distance between medial radial border and lateral ulna border
Small holes act as channel for forearm vasculature
- Holds radius and ulna together
- Acts as site of attachment for muscles in anterior and posterior forearm
- Transfers forces from radius to ulna

Question 5

Fractures

Answer 5

Fractures of radius and ulna usually happen together as they can be thought of as a ring

• Monteggia’s fracture - caused by force behind ulna, proximal shaft of ulna fractured, head of radius dislocates anteriorly at elbow
• Galeazzi’s fracture - fracture of distal radius, ulna head dislocates at distal radioulnar joint