Pediatric elbow fractures: MRI evaluation

Abstract

Magnetic resonance imaging (MRI) was performed in eight patients under the age of 8 years who suffered elbow fractures, to assess possible fracture extension into the distal nonossified epiphysis of the humerus in seven cases and to determine the displacement and location of the radial head in one case. MRI allowed accurate depiction of the fracture line when it extended into the cartilaginous epiphysis. In four cases, MRI findings were confirmed at surgery. In five cases, surgery was obviated because no articular extension of the fracture was seen on MRI (4 cases) or because no displacement was noted (1 case). In one patient, the plain film diagnosis of a Salter type II fracture was changed to Salter type IV on the basis of the MRI findings. It is concluded that MRI might play a role in the preoperative evaluation of pediatric patients presenting with elbow trauma when extension of the fracture cannot be determined with routine radiographic studies.

Elbow injuries in children may be difficult to diagnose by routine clinical and radiographic techniques [1, 4, 12, 14]. Diagnostic difficulty is due to the presence of multiple ossification centers of the distal humeral epiphysis and proximal radius and ulna; these are mostly cartilaginous until the age of 11–12 years and therefore invisible on radiographs.

Following distal radial and distal tibial physeal fractures, epiphyseal elbow injuries are the most frequent epiphyseal injuries [8, 16]. These fractures tend to be unstable and often require surgical intervention. In addition, lasting sequelae such as cubitus valgus and delayed ulnar nerve palsy can occur if these fractures are not treated properly [8]. Most elbow fractures suspected to be unstable by clinical and radiographic evaluation are operated upon without additional imaging. Occasionally, arthrography or computed arthrography are used to assess epiphyseal extension and cartilaginous malignment [1, 3, 4]. Because of its ability to depict cartilage, MRI provides a noninvasive means of gaining information regarding the nonossified epiphysis. The purpose of this article is to present our preliminary experience using magnetic resonance imaging (MRI) for the detection of articular extension of elbow fractures and determination of displacement of fragments.