Presentation
Persistent midfoot pain following inversion injury.
Patient Data
A non-displaced fracture of the anterior calcaneal process is visible, with adjacent small area of bone marrow edema. The medial limb of the bifurcate ligament and the dorsal talonavicular ligament seem to be sprained.
Incidental finding of os peroneum.
The fracture is not appreciable on x-ray, even on an oblique radiograph.
Case Discussion
Fracture of the anterior calcaneal process is an uncommon type of extra-articular calcaneal fracture. It is best depicted on oblique radiograph and can be occult on AP and lateral radiograph. Therefore a cross-sectional imaging study (CT/MR) is useful for detecting this type of fracture.
A small, non-displaced fracture, which involves less than 25% of calcaneocuboid articular surface, like in this case, is treated conservatively (protective weight bearing).