[MR imaging for the evaluation of accompanying injuries in cases of distal forearm fractures in children and adolescents].

INTRODUCTION

The study was made to evaluate the role of MR imaging in pediatric distal forearm fractures by comparison with the findings of plain radiographs and MRI.

MATERIAL AND METHOD

38 patients (27 boys and 11 girls, mean age of 12 years, range 7 to 15 years) with radiographically open distal radius and ulna growth plates requiring first aid for a fracture of the distal third of the forearm, were included in this study. The fractures were diagnosed on plain radiographs and conservative treatment was performed. In 35 patients MR imaging was performed within 3 weeks after the accident and in 3 patients MRI was performed after 6 to 9 weeks because of persistent wrist pain.

RESULTS

Fifteen Salter/Harris II injuries of the radius and 1 of the ulna, 1 torus fracture of the radius and 2 of the ulna, 12 greenstick fractures of the radius and 3 of the ulna, 10 complete displaced radius fractures and 15 ulnar styloid fractures were found on plain radiographs. Twelve patients had evidence of associated triangular fibrocartilage complex (TFCC) lesions in MRI, there was no statistical correlation between TFCC lesions and fracture types, fracture dislocations or patients age (p > 0.5). One patient had an avulsion of the radioscaphocapitate ligament from the radius accompanying a greenstick fracture of the distal radius. 19 bone bruises and two radiographically occult fractures were identified. In 2 patients, a bone marrow oedema was seen in the radial epiphysis immediately adjacent to the germinal zone of the growth plate. In these patients premature physeal arrest occurred.

CONCLUSION

MRI plays an important role in the evaluation of acute pediatric wrist injuries. It allows a better evaluation of osseous lesions than plain radiographs. In our study, a tear of the triangular fibrocartilage complex accompanied distal radius fractures in 32 % of patients. Simultaneous rupture of the TFCC insertion in the fovea ulnaris and ulnar styloid fracture lead to destabilisation of the distal radioulnar joint (DRUJ).