Surgical Construct Associated with Time to Fusion in Double and Isolated Talonavicular Arthrodeses

CATEGORY: Hindfoot; Ankle Arthritis INTRODUCTION/ PURPOSE: Double arthrodesis of the subtalar (ST) and talonavicular (TN) joints, along with isolated TN arthrodesis, are commonly performed for hindfoot osteoarthritis and rigid hindfoot deformity. Few studies have examined the effects of the type of ST and TN fixation constructs on nonunion rate following double and isolated TN arthrodesis procedures. This study evaluates the effect of surgical construct on the union rate and time to fusion in patients undergoing double or isolated TN arthrodesis. METHODS: Retrospective chart review identified 52 patients (52 feet) who underwent double or isolated TN arthrodesis between 2016 and 2021 by a fellowship-trained foot and ankle surgeon with at least six months of follow-up (mean=1.62 years, range=0.50- 4.39 years). Data collected included demographics, medical history, surgical indication, surgical constructs used, complications, reoperations, patient-reported outcome measures, and radiographic measures. ST constructs included one (n=4) or two (n=44; parallel=43, divergent=1) cannulated screws, while TN constructs included dorsal plate (n=2), dorsal plate and screw (n=10), isolated screws (n=3) screw and staple (n=29), or isolated staples (n=13). At the time of their surgery, the mean age was 60.39 (range, 17-80) years, mean body mass index (BMI) was 33.89 (range, 20.74-48.41) kg/m2, and most subjects were non-smokers (94.7%). Mean follow-up duration was 1.62 (range, 0.50-4.39) years. RESULTS: Overall complication and reoperation rates were 26.3% and 12.3%, respectively. Among TN constructs, the time to ST (p=.026) and TN (p=.018) fusion was statistically significantly slower among patients receiving a plate and screw TN construct. Complication rate did not differ by construct, but reoperation rate was significantly higher for the plate and screw TN construct (p=.039). Postoperative Foot and Ankle Outcome Score (FAOS) Quality of Life (p=.028) and Total (p=.016) scores were significantly better among plate and screw TN constructs. CONCLUSION: The utilization of a screw and staple or isolated staple construct have a statistically significantly quicker time to fusion and lower reoperation rates than plate and screw constructs for the TN joint. These findings can be used to guide clinician decision-making while allowing physicians to take their personal construct preference into account, as well as serve as a useful starting point to other researchers interested in investigating the impact of surgical constructs on ST and TN fusions.