45: Ankle Fusion and Tibial Lengthening (LATN Technique) for Failed Ankle Replacement

Fig. 1

Pre-operative standing radiograph showing LLD of 3.5 cm

Fig. 2

Pre-operative lateral radiograph showing collapse of talar component

3 Preoperative Problem List

Failed TAR

Additional LLD of 3.5 cm

Total bone loss expected is = LLD + bone defect after removal of TAR

High suspicion of infection

4 Treatment Strategy

Remove TAR and use Ilizarov/TSF to close defect with acute and gradual shortening.

Take cultures at surgery to rule out infection. Hold pre-operative antibiotics to get reliable cultures.

Staged surgery (4–6 weeks later) to lengthen the tibia. Bone defect of 5 cm after removal of TAR is anticipated. Total bone loss is equal to LLD (3.5 cm) + bone defect after TAR removal (5 cm) = 8.5 cm.

Use LATN technique to shorten time in frame.

5 Basic Principles

Excise TAR through medial and lateral incisions.

Acute plus gradual shortening of bone defect with TSF.

Avoid bone graft in setting of infection.

Acute shortening of more than 3 cm is inadvisable. This will make wound closure difficult and can adversely affect neurovascular status.

Check pulses during surgery to make sure you are not acutely shortening too much.

Total bone loss is preexisting LLD plus bone defect from removal of TAR.

LATN shortens time in frame by substituting an intramedullary nail during the consolidation phase. The rod is inserted before the frame is removed. There is no contact between internal and external fixation. The proximal tibial external fixation is placed peripherally in the bone out of the path of the intramedullary rod.