An Undescribed Monteggia Type 3 Equivalent Lesion: Lateral Dislocation of Radial Head with Both-Bone Forearm Fracture

Abstract

Monteggia fractures are accepted as hard-to-recognize and easy-to-handle fractures. Adequate radiographic investigations and clinical examinations are necessities. This case holds unique features involving diagnosis and treatment. In this case, the radial head was dislocated laterally while both bones were fractured in the proximal diaphysis, being the first to be mentioned in the literature. Closed reduction of the ulna is the preferred method of handling and almost always results in reduction of the radial head. Literature obligates ulnar reduction as a preliminary to reduce and stabilize the radial head. Closed reduction reduced the ulna but the radial head was not reduced. Hence an intramedullary K-wire was used to reduce the radial head and a long arm cast was used to stabilize the reduction. The operation was successful and follow-up showed no complications.

Figure 1

Oblique forearm radiographs taken in outside clinic revealed both bone forearm fractures and no anterior displacement of radial head.

Figure 2

AP (a) and lateral (b) views of the healthy side with radiocapitellar lines. AP (c) and lateral (d) views of the injured side with radiocapitellar lines after closed reduction. Arrow head shows laterally dislocated radial head.

Figure 3

Anatomic reduction of the ulnar fracture in AP (a) and lateral (b) views. Arrow heads show hardly recognizable ulnar fracture lines.

Figure 4

Postoperative radiographs show the radial head and anatomic ulnar reductions in lat (a), AP (b), and axial (c) views.

Figure 5

Radiographs after K-wire removal show successful union and reduction at the 6th week.

Figure 6

Clinical photos show full ROM of elbow and forearm rotation at the 8th week.