Clinical impact of MRI in acute wrist fractures.

The purpose of this study was to evaluate the clinical impact of MRI in the early diagnosis of wrist trauma. High-resolution MR imaging was performed on a 1.5-T unit (Symphony Quantum, Siemens, Erlangen, Germany) using coronal and axial T1- and T2-weighted fat-saturated turbo-spin-echo sequence via a dedicated wrist coil within a mean of 6.6 days after initial radiographs in 54 patients (56 wrists) with clinical suspicion of wrist fractures and normal plain or indistinct radiographs. Initial radiographs were evaluated independently by two senior radiologists and the hand surgeon without knowledge of the MRI findings. The initial treatment protocol was based on evaluation of plain films and clinical findings by the hand surgeon. Treatment protocol was changed after MRI examination if necessary. In 31 of 56 wrists MRI findings resulted in a change of diagnosis. There were false-positive diagnoses on plain radiographs in nearly one half n=25 of the patients. False-negative diagnoses on plain radiographs resulted in 6 cases. Magnetic resonance imaging detected additional injuries of soft tissue in more than one third n=20. In 22 of 56 wrists the period of immobilization could be shortened or ended, in 12 of 56 it was prolonged, and in 3 of 56 a surgical intervention was necessary. In 19 wrists MRI had no therapeutic consequences. Our data demonstrate the high clinical impact of MRI in the detection of acute wrist fractures. We recommend MRI of the wrist immediately on the day of trauma if there is clinical suspicion and normal plain radiographs. Accurate diagnosis by MRI examination within the first days following trauma may reduce economic costs due to shortened immobilization time in cases with a suspected fracture but plain radiographs.