[External fixator: temporary fixation and soft tissue management of the ankle]

Joint-spanning transfixation of the ankle joint aims at mostly temporary retention of the reduction, i.e. restoring length and axial alignment and stabilization of the ankle mortise in highly unstable fractures around the ankle and under critical soft tissue conditions. In selected cases, external fixation serves as an additional stabilization also following completed internal fixation or the fracture can be treated in the external fixator. The goal of surgery is to allow quick soft tissue recovery, prevention of redislocation and stabilization of the ankle and adjacent structures.

a) Fractures of the tibial pilon; b) very distal, extra-articular lower leg fractures (without the option for pin positioning in the distal fragment); c) highly unstable malleolar fractures with tendency to subluxation and dislocation fractures; d) critical soft tissue conditions around the ankle; e) dislocation fractures of the talus, Chopart and Lisfranc joints (if necessary with additional transarticular transfixation).

Missing consent to surgery by the conscious patient, life-threatening general condition by other prioritized injuries.

Percutaneous pin placement of the appropriate caliber into so-called safe zones of the tibia, metatarsus and calcaneus, as needed. Additional transfixation of the Chopart and Lisfranc joints with K‑wires as needed. Fixation of the struts with the foot in a neutral position. Besides consideration of biomechanical principles, pin placement must be done in anticipation of the definitive stabilization and future approaches respecting the anatomical structures while achieving maximum stability and soft tissue protection.

Following initial transfixation, elevation of the injured leg for soft tissue protection, local cooling and bed rest are indicated. In cases of compartment syndrome and open fractures with temporary soft tissue coverage, second look surgery after 24-72 h is mandatory. For exact fracture analysis and optimal planning of the definitive surgical strategy, the indications for CT imaging should be generously considered. The timing of definitive care depends on the local soft tissue status and the overall condition of the patient.

The presence of a dislocation at the time of the accident represents a negative prognostic factor for ankle fractures. Higher rates of posttraumatic arthrosis are also found in pilon fractures and trimalleolar fractures, direct cartilage damage and rupture of the syndesmosis. In cases of anatomic reconstruction of the mortice and ankle joint congruence, good to excellent results can be achieved in 75-89%.