An unusual monteggia equivalent: a case report with literature review

Abstract

Monteggia fracture dislocations are uncommon in childhood. Over a period of time, various equivalents of this entity have been described. These fractures with concomitant elbow injuries are exceedingly rare in young children. We present a case of a 6-year-old boy who sustained a fracture of proximal ulna with ipsilateral supracondylar fracture humerus. We suggest that the fracture pattern can be included under type I Monteggia equivalent on the basis of its characteristics, biomechanics and the mode of injury.

Keywords: Monteggia equivalents; Monteggia lesions; Supracondylar fracture.

Fig. 1

Pre reduction AP radiograph showing displaced supracondylar fracture humerus with fracture of middle third shaft of ulna

Fig. 2

Pre reduction lateral radiograph showing supracondylar fracture humerus (Gartland type 3) with fracture of middle third shaft of ulna (20⁰ anterior angulation)

Fig. 3

Post-reduction radiograph showing acceptable alignment

Fig. 4

Follow-up radiograph at 12 months showing fracture healing with acceptable alignment

Fig. 5

Line diagram showing hyperpronation force, which lead to failure of supracondylar area of humerus before radial head dislocation or fracture of radial neck. Instead of the anterior dislocation of the radial head or the radial neck fracture, intact radio-capitellar and proximal radio-ulnar joints moved along with distal supracondylar fragment in the attitude of deforming force