Isolated trapezoid fracture: four cases of a rare fracture on MRI

Isolated trapezoid fractures have been rarely reported in the literature and are occult on routine radiography. Previously described cases have utilized computed tomography (CT) to make this diagnosis; however, magnetic resonance imaging (MRI) is better for soft tissue evaluation and can detect fractures which may be occult on CT. We report 4 cases of isolated trapezoid fractures diagnosed by MRI in 4 males after remote trauma, ages ranging from 19 to 62. In each case, initial work-up with radiography, and one case with CT, was negative for a fracture but an MRI was ultimately obtained due to high clinical suspicion, resulting in the diagnosis of an isolated trapezoid fracture. Based on literature review, these are the first cases of isolated trapezoid fracture diagnosed by MRI. MRI offers several advantages over CT and is more valuable in cases of suspected occult fracture, given the ability to evaluate soft tissue and ligamentous injuries.