Outcome of Ilizarov ankle arthrodesis

Many operative techniques have been described for ankle arthrodesis, with varying fusion rates. In revisions, the fusion rate is lower than in primary arthrodesis. Recent reports have described good results after Ilizarov ankle arthrodesis. However, descriptions were qualitative, with none using an accepted score. We describe our experience with this technique and functional outcomes in our patients.

Seventeen patients (average age 48 years) had primary or revision unilateral ankle arthrodesis using the Ilizarov technique at two centers. Diagnoses included post-traumatic arthritis and Charcot arthropathy. Three patients had talar osteonecrosis. Time in the frame averaged 15 weeks and in a cast 4 weeks. Followup averaged 6 years. Outcome was assessed using the American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale.

All ankles achieved solid fusion. The average AOFAS score was 65 out of 86 possible. Based on this, results were defined as excellent in three patients, good in eight, fair in four, and poor in two. Minor complications were common, all resolving with local treatment. No deep infection developed. One fusion malunited in 8 degrees of varus.

The Ilizarov external fixator has numerous advantages applicable to ankle fusion, including: stable fixation, respect for soft tissues, and the possibility of postoperative alignment 'fine-tuning'. Additionally, the ability to direct forces through or around skeletal elements allows varying of the load through the skeletal elements, allowing early weightbearing. The Ilizarov technique, with its high union rate, may be considered for any ankle arthrodesis but is especially useful in complex cases such as revisions, talar osteonecrosis, soft-tissue compromise, and infection. Early weightbearing is an added benefit.