Monteggia fracture- dislocation

Monteggia fracture- dislocation has two components- fracture of upper- third part of ulna (bone of medial side) and simultaneous dislocation of proximal part (the head) of Radius. Check out the mnemonic to memorise it here.

The injury is caused by a fall on an outstretched hand with the forearm forced into excessive prone position (hyperpronation injury).

Types of Monteggia fracture and dislocation (Bado's classification) :-
Type I- Extension type- Angulation of proximal part of ulna anteriorly and dislocation of the head of Radius anteriorly. This type is seen in 60% patients.

Bado type I lesion (most common)

(Note- Posterior Interosseous nerve may get paralysed in Monteggia fracture and dislocation that is a result of anterior radial head dislocation in type I of Bado, unless reduced by manual pressure).

Type II- Flexion type- Fracture of proximal part of ulna and posterior dislocation of radial head.
Type III- Lateral type- Fracture of ulnar metaphysis and dislocation of head of Radius laterally.
Type IV Combined type Fracture of ulnar as well as radial shafts with dislocation of radial head anteriorly.


Diagnosis of Monteggia fracture and dislocation:- Check for both components- the fracture as well as displacement coz there could be an isolated fracture of ulna as due to nightstick injury.
X- rays of the forearm (Antero-posterior and lateral view) are diagnostic.

Treatment- Conservative management in children with closed reduction (resetting of bones and casting) accompanies the high risk of displacement thus causing malunion.
Standard treatment procedure in Monteggia fracture and dislocation is Osteosynthesis of the ulnar shaft (Open Reduction and Internal fixation) in children as well as adults to improve stability of the radio-ulnar joint and mobilise so as to prevent stiffness.


Thats all
- Jaskunwar Singh