Perceived risk factors for nonunion following foot and ankle arthrodesis

Background: A major complication of foot and ankle arthrodesis is nonunion, which occurs in approximately 12% of cases. Various factors influence a patient’s risk for nonunion following foot and ankle arthrodesis. We surveyed international foot and ankle surgeons to determine (1) risk factors perceived most important for nonunion, (2) factors considered absolute contraindications for arthrodesis, and (3) differences among expert groups regarding perceived risk factors and their stratification. Methods: A questionnaire was e-mailed to members of a major foot and ankle journal editorial board and four foot and ankle society executive committees. The relative risk of 18 potential nonunion risk factors was rated from 1 to 10, using smoking 1 pack/day as a benchmark score of 5.00. Results: The response rate was 72% (100/139); 81% declared foot and ankle surgery encompasses >90% of their practice. The highest perceived risk factors (p < 0.001) were smoking 2 packs/day (mean score 8.69), lack of fusion site stability (8.66), and poor local vascularity (7.66). The least important risk factors (p < 0.001) were perceived to be age >60 years (mean score 2.54), rheumatoid arthritis (3.05), and osteoporosis (3.56). The most frequently cited absolute contraindications to arthrodesis surgery were local infection (46%), poor local vascularity (41%), and smoking (32%). Conclusion: To improve arthrodesis outcomes, resource allocation and patient and surgeon education should focus on smoking, construct stability, and local vascularity. Development of an objective nonunion risk assessment tool to identify patients at risk for nonunion using these results could help maximize the efficiency of available resources.