Syndesmotic Screw in Neutral Position Versus Maximum Ankle Dorsiflexion in Ankle Fractures; Comparative Study.

Ankle fracture is one of the most common orthopedic injuries. Approximately, 20% of surgically treated ankle fractures are associated with syndesmotic instability.According to the mechanism of the injury the syndesmotic disruption should be considered in Danis-Weber C-type fractures. However, such injuries were also frequently seen in Danis-Weber B-type fractures. Failure to detect and repair syndesmotic injuries early may result in poor clinical outcomes and complications affecting ankle function, such as long-term residual pain, post traumatic arthritis, and ankle impingement syndromes. Therefore, aggressive treatment is important when facing syndesmotic instability . The distal tibiofibular syndesmosis is important for stability of the ankle mortise and thus for weight transmission and walking. Syndesmotic injuries are most commonly associated with fibular fractures, but they can also occur in isolation or with damage to the lateral ankle ligament after traumatic supination. The need for syndesmotic fixation of the distal tibiofibular joint has been controversia. fracture does not correlate reliably with the extent of the interosseous membrane tears identified on MRI of ankle fractures, and thus estimation of the integrity of the interosseous membrane and subsequent need for trans-syndesmotic fixation cannot be based solely on the level of the fibular fracture. An intraoperative syndesmotic stress test can establish the presence or absence of syndesmotic instability, evaluating the integrity of the syndesmosis by grasping the stabilised fibula with a hook or clamp and pulling it laterally. If more than 3 or 4 mm of lateral displacement occurs, syndesmotic fixation is necessary. Most authors recommend surgical placement of a trans-fixation screw after anatomical reduction of the syndesmosis if a disruption is diagnosed to avoid complications.The main aims of treatment for dislocation of the distal tibiofibular syndesmosis are to restore the original anatomy and