Monteggia Fracture-dislocation

What is it?

• Described by Monteggia in 1814, it is a fracture of the ulna associated with dislocation of the radial head. The radial head may dislocate anteriorly, posteriorly or laterally.

Classification

Bado's classification is most commonly used:

• Type 1 - anteriorly angulated ulna fracture + anterior radial head dislocation
• Type 2 - posterior angulated ulna + posterior / posterolateral radial head dislocation
• Type 3 - ulnar metaphysis + lateral / anterolateral radial head dislocation
• Type 4 - proximal third radius and ulna + anterior radial head dislocation

Figure 1 - Monteggia fracture-dislocation

Aetiology

• Most commonly from a fall onto the hand with forced pronation of the forearm
• Also from:
• Direct violence
• Hyperextension of the hand.

Clinical Features