Surgical Outcome of Hindfoot Fusion using a Retrograde Hindfoot Fusion Nail

CATEGORY: Hindfoot INTRODUCTION/PURPOSE: TTC fusions are often performed as a salvage procedure in patient with severe hindfoot arthritis or hindfoot deformity. Comorbidities in this patient collective are frequent, leading to increased risk of postoperative complication. The purpose of this study was to evaluate the surgical outcome regarding union rate, reoperation rate and adverse events using a retrograde hindfoot fusion nail. METHODS: Patient records of a single center were retrospectively reviewed in which a retrograde hindfoot fusion nail was utilized for hindfoot fusion between July 1st, 2009 and August 31st, 2018. These records included age, gender, BMI, comorbidities, indications for surgery, non-union, re-operation rates and adverse events related to the surgery. The fusions were performed by 4 fellowship trained foot and ankle surgeons at a tertiary care teaching hospital. 58 cases were identified consecutively, in 51 cases a TTC fusion was performed, in 7 cases a tibiotalar fusion with preexisting talocalcaneal fusion. 22 fusions were arthroscopic and 36 open. The average age of patients was 59 years, the average BMI 29. Main indication for the hindfoot fusion were arthritis (55%) and complex hindfoot deformity (43%). RESULTS: An overall union rate of 89.66% was achieved, 5 non-union tibiotalar and 1 non-union tibiotalar + talocalcaneal was documented. In the group of arthroscopic fusion the non-union rate was 9.09%, in the open group 11.11% respectively. The non- union group included patient with elevated BMI (50%), Diabetes mellitus (33%) and smoking (33%). Adverse events were documented in 21%. The reoperation rate was 17%, mostly due to deep infection or wound complication requiring surgical debridement. No patient in the arthroscopic fusion group needed a reoperation due to deep infection or wound complication, whereas in open surgery this rate was 27.78%. CONCLUSION: A union rate of 89.66% was achieved using a retrograde hindfoot fusion nail in a high risk patient population for non- union. Arthroscopic preparation of the tibiotalar and the subtalar joint seem to prevent postoperative wound complications.