Acute syndesmotic injuries in ankle fractures: From diagnosis to treatment and current concepts

Abstract

A stable and precise articulation of the distal tibiofibular syndesmosis maintains the tibiofibular relationship, and it is essential for normal motion of the ankle joint. The disruption of this joint is frequently accompanied by rotational ankle fracture, such as pronation-external rotation, and rarely occurs without ankle fracture. The diagnosis is not simple, and ideal management of the various presentations of syndesmotic injury remains controversial to this day. Anatomical restoration and stabilization of the disrupted tibiofibular syndesmosis is essential to improve functional outcomes. In such an injury, including inadequately treated, misdiagnosed and correctly diagnosed cases, a chronic pattern characterized by persistent ankle pain, function disability and early osteoarthritis can result. This paper reviews anatomical and biomechanical characteristics of this syndesmosis, the mechanism of its acute injury associated to fractures, radiological and arthroscopic diagnosis and surgical treatment.

Keywords: Ankle; Distal tibiofibular joint; Fracture; Injury; Syndesmosis; Trauma.

Figure 1

Anatomy of the distal tibiofibular syndesmosis: anterior view, posterior view, lateral view and proximal and distal coronal view. AITFL: Anterior inferior tibiofibular ligament; IOL: Interosseous ligament; IOM: Interosseous membrane; PITFL: Posterior inferior tibiofibular ligament; TTFL: Transverse tibiofibular ligament.

Figure 2

Radiographs representing the three types of ankle fractures according to Danis-Weber. A: Infrasyndesmotic; B: Trans-syndesmotic; C: Suprasyndesmotic.

Figure 3

X-ray of the right ankle: standard projections. A: Anteroposterior; B: Mortise; C: Laterolateral views.

Figure 4

Normal values of tibiofibular clear space, tibiofibular overlap and medial clear space in left ankle mortise projection. MCS: Medial clear space; TFCS: Tibiofibular clear space; TFO: Tibiofibular overlap.

Figure 5

Suspect of a left syndesmotic lesion. A: Comparative X-ray and based on the measurements of the tibiofibular clear space, tibiofibular overlap and medial clear space, the exam was considered negative; B: Computed tomography assessment showed a difference (> 2 mm) between both sides (arrow), demonstrating the presence of a syndesmotic lesion.

Figure 6

Postoperative computed tomography scans of a syndesmotic lesion showing a widened tibiofibular space (arrows) indicative of an inadequate reduction.

Figure 7

Intraoperative view. A: Modified Cotton test with hook; B: Modified Cotton test with reduction clamp.

Figure 8

Type B ankle fracture. A: Preoperative X-rays; B: Radiographs 1 mo after surgery; C: Radiographs 2 mo after surgery following removal of the screw that was discovered broken (arrow) during the second procedure.

Figure 9

Type C ankle fracture and dislocation. A: Preoperative X-rays; B: Postoperative X-rays; C: Radiographs performed 3 mo after trauma with breakage of the proximal intersyndesmotic screw (arrow).

Figure 10

Trimalleolar right ankle fracture associated with dislocation. A: Preoperative X-rays; B and C: Computed tomography sagittal views with posterior malleolar fracture [tibial portion (B) and peroneal portion (C)]; D: Computed tomography axial view; E: Three dimensional computed tomography; F: Postoperative radiographs after fixation of the fibula and of the lateral part of the posterior malleolus with a P-A screw through a posterolateral approach and of the medial malleolus and of the tibial part of the posterior malleolus through a posteromedial approach (plates and screws); G: X-rays 8 mo following surgery with consolidation.

Figure 11

Type C ankle fracture. A: Preoperative X-rays and computed tomography performed after closed reduction with diastasis (asterisks); B: Intraoperative positioning of the 3.5 mm intersyndesmotic screw with the foot positioned at 90° of dorsiflexion; C: Postoperative radiographs; D: Removal of the screw 2 mo after surgery; E: Views 6 mo after trauma with fracture consolidated.