Intermediate-Term Clinical Outcomes After the Shortening Arthrodesis for Ankle Arthropathy with Severe Bone Defect

Background/Objectives: The most common limb-salvage procedure for end-stage ankle arthropathy with severe bone defect is arthrodesis. Successful fusion requires rigid metal fixation, effective filling of the bone defect space, and maximal securing of the contact area between the tibia and talus. In cases with severe bone defect, sufficient grafting using autogenous bone alone is limited, and there is still controversy regarding the effectiveness of allogeneic or xenogeneic bone grafting. This study aimed to evaluate the intermediate-term clinical outcomes after shortening arthrodesis using fibular osteotomy for ankle arthropathy with severe bone defect. Methods: Twenty-two patients with shortening ankle arthrodesis were followed up ≥ 3 years. All operations were performed by one senior surgeon and consisted of internal fixation with anterior fusion plate, fibular osteotomy, and autogenous bone grafting. The causes of ankle joint destruction were failed total ankle arthroplasty (7 cases), neglected ankle fracture (6 cases), delayed diagnosis of degenerative arthritis (5 cases), avascular necrosis of talus (2 cases), and diabetic neuroarthropathy (2 cases). Clinical outcomes including daily living and sport activities were evaluated with the Foot and Ankle Outcome Score (FAOS) and the Foot and Ankle Ability Measure (FAAM). Radiological evaluation included fusion rate, time to fusion, leg length discrepancy, and degenerative change in adjacent joints. Results: The FAOS and FAAM scores significantly improved from a mean of 21.8 and 23.5 points preoperatively to 82.2 and 83.4 points at final follow-up, respectively (p < 0.001). Visual analogue scale for pain during walking significantly improved from a mean of 7.7 points preoperatively to 1.4 points at final follow-up (p < 0.001). The average time to complete fusion was 16.2 weeks, and was achieved in all patients. The average difference in leg length compared to the contralateral side was 11.5 mm based on physical examination, and 13.8 mm based on radiological examination. During the average follow-up of 56.2 months, no additional surgery was required due to progression of degenerative arthritis in the adjacent joints, and no cases required the use of height-increasing insoles in daily life. Conclusions: Shortening ankle arthrodesis using fibular osteotomy and anterior fusion plate demonstrated satisfactory intermediate-term clinical outcomes and excellent fusion rate. Advantages of this procedure included rigid fixation, preservation of the subtalar joint, effective filling of the bone defect space, and maximal securing of the contact area for fusion. The leg length discrepancy, which was concerned to be a main shortage, resulted in no significant clinical symptoms or discomfort in most patients.