Takedown of Ankle Arthrodesis With Insufficient Fibula: Surgical Technique and Intermediate-Term Follow-Up

Conversion of ankle arthrodesis to total ankle arthroplasty has recently gained popularity. However, technical challenges are present when treating patients without a sufficient fibular buttress. We describe a technique for restoration of an adequate fibular buttress using an iliac crest bone graft or malleolar relocation. The results of 10 patients with an average follow-up period of 56 (range 24 to 123) months are presented. Of the 10 patients, 3 underwent tricortical iliac bone augmentation of the fibula, 4 underwent repositioning of the remnant fibula, and in 3, the in situ fibula was used. The average interval from fusion to takedown was 15.1 (range 5 to 35) years, and the average age at takedown was 52.8 (range 33 to 75) years. The average improvement in the American Orthopaedic Foot and Ankle Society Ankle-Hindfoot scale and Buechel-Pappas scale scores was 35.8 (range 30 to 46) and 34 (range 25 to 42), respectively. Three patients underwent a total of 7 subsequent operations related to the ankle implant. Only 1 of the patients had any residual frontal plane deformity. None of the patients exhibited any component subsidence; however, 2 patients experienced asymptomatic lateral talar component overgrowth. The improvement in the clinical scores in this group of patients suggests that takedown of an ankle arthrodesis with an insufficient fibula is a viable option to improve function. Various techniques to restore the lateral buttress can be used even with complete absence of the distal fibula.