On the Treatment of Unstable Ankle Fractures

Abstract

Ankle fractures constitute about 10% of all fractures. Unstable ankle fractures require surgery to restore ankle stability and congruity, thereby reduce the risk of pain, poor function, and posttraumatic osteoarthritis. Today, several surgical methods are used as newer techniques are introduced to improve the outcome after surgery. The goal of this doctoral thesis was to investigate different surgical methods for treatment of acute unstable ankle fractures. Two randomized controlled trials were conducted; one comparing nail and plate fixation of acute unstable AO/OTA type 44-B ankle fractures in elderly patients, and one comparing suture button (SB) and tricortical screw fixation of acute AO/OTA type 44-C ankle fractures. Additionally, a biomechanical study was conducted comparing posterior malleolar screw and trans-syndesmotic SB fixation for treatment of ankle injuries with posterior malleolar fracture (PMF) and an unstable syndesmosis. Equivalent functional outcome was found between nail and plate fixation at 24 months; however, a higher number of complications and secondary surgical procedures was found after nail fixation. When comparing SB and tricortical screw fixation, equivalent functional outcome and no significant difference in tibiofibular distance was found at 24 months. Also, no difference in complication or reoperation rate was found. Posterior malleolar screws with anterior inferior tibiofibular ligament (AITFL) augmentation resulted in best biomechanical stability with external rotation of an ankle injury with PMF and unstable syndesmosis. With internal rotation, all repairs that included posterior malleolar screws resulted in acceptable stability. We conclude that plate fixation should be the treatment of choice for acute unstable ankle fractures in elderly patients in general, acute syndesmotic injuries may be treated with a SB or tricortical screw, and posterior malleolar screw fixation with AITFL augmentation may be preferred in patients with acute ankle injury involving a PMF and an unstable syndesmosis.