MR imaging of anterosuperior calcaneal process fractures

OBJECTIVE. Fractures of the anterosuperior calcaneal process can be both cl inically and radiographically difficult to detect yet, if not recognized an d immobilized early, may result in painful nonunion. The purpose of this st udy was to show that MR imaging is sensitive in the detection of such subtl e or radiographically occult fractures, that the pattern of marrow edema co rresponds to the two known mechanisms of injury, and that MR imaging can do cument both healing and nonunion of these fractures. CONCLUSION. MR imaging can reveal subtle or nondisplaced fractures of the a nterosuperior calcaneal process. Also, MR imaging can be used to document h ealing. The pattern of marrow edema limited to the anterosuperior calcaneal process corresponds to the bifurcate ligament avulsion mechanism of injury . Edema in both the anterosuperior calcaneal process and the cuboid is caus ed by the impaction mechanism of injury.