Injury mechanism, fracture characteristics and clinical treatment of pilon fracture with intact fibula-A retrospective study of 23 pilon fractures.

Objective: The effect of intact fibula on pilon fracture is not completely elucidated. We retrospectively analysed pilon fractures with intact fibula at our hospital over a 4 year period to understand the injury mechanism, fracture characteristics, treatment strategy and prognosis of this fracture.

Methods: Pilon fracture patients with intact fibula treated in our hospital from January 2010 to December 2014 were observed. OA/ATO fracture type, Ruedi-Allgower classification and fracture characteristics were summarised. The following data were collected from the charts: operative time, operative approach, fixation, fracture healing time, ankle joint Mazur scores, Burwell-Charnley fracture reduction scores and postoperative complications.

Results: Twenty-two patients were followed up with a mean follow-up time of 17.6 months (10-27 months). The examination results showed the existence of distal tibiofibular syndesmosis injuries, medial malleolus, posterior malleolar, and anterior tibial fractures, and talus-fibula relationship changes, which accounted for 65.2%, 69.3%, 73.9%, 100% and 26.1%, respectively. 19 cases underwent internal fixation, with an average operation time of 108 min. The mean fracture healing time was 6.74 months. The Mazur ankle score showed excellent and good ratings of 86.9%. The Burwell-Charnley fracture reduction score had good and fair ratings of 95.7%. Skin infection occurred in two cases.

Conclusion: Pilon fracture with intact fibula is mostly caused by medium-low energy injury when the ankle is at neutral or varus position. Multi-part fractures commonly occur at the distal tibial articular surface because the energy is concentrated on the tibia. In general, one single anterior approach can complete open reduction and internal fixation operation with satisfactory clinical outcomes in most cases.