The spectrum of this injury varies from isolated comminution of the lateral wall to complete comminution of the entire bone.
Usually these injuries present because of lateral column shortening with resultant cuboid crushing, in which case it is referred to as a nutcracker injury. It can also be associated with multiple midfoot injuries.
There is swelling, bruising, and point tenderness at the dorsolateral aspect of the foot.
Typically, there will be deformity of the foot with shortening of the lateral column.
The patient will most often be unwilling to walk and put weight on the lateral aspect of the foot.
This injury is frequently part of a Lisfranc or Chopart injury, in which case there may also be bruising at the plantar aspect and medial pain. A high index of suspicion is needed to ensure the exclusion of Lisfranc and Chopart injuries.
In the multi-injured patient, foot fractures are often overlooked and are picked up on the secondary survey. In the unconscious patient, one must rely on a careful physical examination. Swelling, crepitus, or a deformity are suggested signs of underlying injury and should be followed up with appropriate x-rays and CT.
AP image of nutcracker injury.
CT scan of nutcracker injury.
The multifragmentary fracture of the cuboid, the "nutcracker fracture," is a valgus stress injury where the cuboid is crushed between the 4th and 5th metatarsal and the calcaneum.
This injury is frequently part of more complex midfoot injuries such as the Lisfranc or Chopart injury.