Bosworth fracture: A report of two atypical cases and literature review of 108 cases

Summary Introduction The Bosworth fracture was originally defined as a bimalleolar fracture-dislocation of the ankle (Weber Type B), with the proximal fibular fragment entrapped behind the posterior tubercle of the distal tibia. Methods (1) A 73-year-old female sustained a Weber type C fibular fracture and posterior malleolus fracture. The distal fragment of the fibula was displaced into a gap between the distal tibia and the posterior malleolus fragment. Open reduction and fixation with two syndesmotic screws was performed. (2) A 51-year-old woman sustained a Weber type B fibular fracture and a posterior tibial pilon fracture (AO Type B). The proximal fibular fragment was entrapped between the anterior part of the fibular notch and the posterior tibial fragment. Treatment consisted of open reduction and plate fixation of the distal fibula and posterior pilon. Results Four years postoperatively, the first patient did not have any subjective complaints. The second patient, two and a half years after the injury, suffered from pain on exercise, limited ankle range of motion and radiographic evidence of osteoarthritis. We found 108 cases in the literature describing Bosworth fractures, Bosworth-like fractures or Bosworth lesions, their common feature being posterior dislocation of the proximal or distal fragment of the fibula, or of an intact fibula, from an intact fibular notch and its entrapment behind the posterior tubercle of the tibia. Some authors also include trimalleolar or pilon fractures with the fibular fragment entrapped in the fracture line between the distal tibia and the posterior malleolus fragment. Conclusions The Bosworth fracture has to be suspected in case of a marked external rotation of the foot with the ap radiograph showing a typical tibiofibular overlap, cortical density at the apex of the medial tibial plafond, and posterior subluxation of the talus the lateral view. CT scanning should be performed. Early open reduction and internal fixation is the treatment of choice. A thorough pre- and intraoperative analysis should address associated injuries to the ligaments, cartilage, muscles, tendons, and vessels around the ankle including the potential risk of development of a compartment syndrome.