Isolated fibula fractures occur in three locations: (a) proximal fibula fracture due to an avulsion injury of the fibular collateral ligament secondary to a twisting of the knee, (b) distal fracture associated with an ankle syndesmotic injury due to twisting of the ankle, and (c) fracture of the fibula shaft due to a direct blow, such as a football helmet striking the lateral side of the leg.

The history of injury directs the physical examination, which shows point tenderness along the shaft of the fibula if fractured. If a proximal fibula fracture is present, examine the function of the peroneal nerve, which wraps around the fibular neck. In twisting injury of the ankle, examine the medial and lateral ankle for point tenderness. Plain radiographs include anteroposterior/lateral/mortise views of the ankle. If there is tenderness of the fibula proximally, then full-length anteroposterior/lateral tibia views are warranted.