Table 1.

Classification systems for Monteggia fracture-dislocation.

Bado Classification for Monteggia injuries3		Letts Classification for paediatric Monteggia injuries1
Type	Description	Type	Description
Type I	Anterior radial head dislocation and diaphyseal ulna fracture with anterior angulation	Type A	Anterior radial head dislocation and apex anterior ulnar bending (plastic deformation)
Type II	Posterior or posterolateral radial head dislocation and diaphyseal ulna fracture with posterior angulation	Type B	Anterior radial head dislocation and apex anterior greenstick ulnar fracture
Type III	Lateral or anterolateral radial head dislocation and proximal metaphyseal ulna fracture	Type C	Anterior radial head dislocation and complete apex anterior ulnar fracture
Type IV	Anterior radial head dislocation, proximal 1/3 diaphyseal fracture of both radius and ulna	Type D	Posterior radial head dislocation and apex posterior ulnar fracture
		Type E	Lateral radial head dislocation and greenstick fracture of the ulna