Monteggia type IV fracture in a child with radial head dislocation irreducible by closed means: a case report

Abstract

Background: Fractures of the proximal third of the ulna and radius with associated anterior radial head dislocation are uncommon in children. Early recognition and appropriate management are essential to prevent long-term consequences of loss of forearm rotation, cubitus valgus, elbow instability and chronic pain.

Case presentation: We present the case of a 3-year-old Caucasian boy who attended the emergency department following an un-witnessed fall, resulting in right elbow and forearm pain, swelling and deformity. Clinical and radiological examination revealed a Monteggia type IV fracture-dislocation.The patient was treated with closed manipulation and percutaneous fixation of both bone forearm fractures with intra-medullary wires. After failed attempts at closed reduction, open reduction of the radial head was required.The block to reduction was due to a buttonholing of the radial head through the anterior joint capsule, with interposition of the capsule in the radiocapitellar joint. Subsequently, alignment was maintained with fracture healing. Follow-up at five months showed a full range of elbow movement with no adverse symptoms.

Conclusion: Monteggia lesions of the paediatric elbow, albeit uncommon, should be considered in all forearm fractures. Accurate reduction of the radiocapitellar joint is crucial to prevent significant long-term consequences and failed closed reduction requires open reduction. Here we have described the management of a rare type IV lesion in which there was buttonholing of the radial head through the anterior capsule, causing the radiocapitellar dislocation to be irreducible (even after fixation of the radial and ulnar fractures).

Figure 1

Pre-operative radiographs demonstrating displaced both bone forearm fractures.

Figure 2

Subsequent further imaging in plaster demonstrating an anterior dislocation of the radiocapitellar joint.

Figure 3

Intra-operative screening images demonstrating the sequence of steps resulting in successful reduction of the fractures and radiocapitellar joint. (a) Closed reduction of ulna did not relocate radial head; (b) Proceeded onto reduction of radius with 2 mm titanium elastic nail but radiocapitellar joint remained dislocated; (c) Anatomic reduction of ulna with percutaneous 2 mm stainless steel wire also did not result in reduction; (d) After open reduction via a postero-lateral approach resulting in successful reduction.

Figure 4

8 weeks post-operative radiographs demonstrating union of both radius and ulnar shaft fractures with successful maintenance of radiocapitellar joint reduction.