Incidence and Factors Associated With Nonunion following Naviculocuneiform Joint Arthrodesis

Background: Nonunion following naviculocuneiform (NC) joint arthrodesis is a well-recognized complication. Most studies reporting nonunion rates involve a limited number of cases or focus on a single disease entity. Moreover, there is variation between studies with regard to the number of articular facets included in the arthrodesis as well as the fixation construct used, with no clear evidence indicating how these factors influence union. This study, using the largest cohort to date, aims to investigate the nonunion rate following NC joint arthrodesis and to identify demographic and surgical factors associated with nonunion.Methods: One hundred ten feet in 100 patients who underwent NC joint arthrodesis between 2016 and 2023 at a single institution were retrospectively identified. The indications for surgery included osteoarthritis (n = 89), deformity (n = 10, flatfoot or cavus), and rheumatoid arthritis (n = 11). Charcot arthropathy was excluded. Nonunions were defined by radiographic review and were further categorized as symptomatic or asymptomatic. Demographic and surgical factors, including isolated medial NC facet vs multiple NC facet arthrodesis, fixation construct, concurrent arthrodesis of other joints, and type of bone graft used, were included in the regression analysis to determine their association with nonunion.Results: The overall nonunion rate was 27.3% (30/110 cases), with 15.5% (17 cases) presenting as symptomatic nonunions. There were no significant differences in the nonunion rates among different indications for NC arthrodesis (P = .9404). A statistically significant difference in nonunion rates was observed between patients undergoing isolated medial facet arthrodesis (38.2%) and those undergoing multiple facet arthrodesis (16.4%, P = .0102). After performing multivariate analysis adjusted for potential confounders, age (OR 1.08, 95% CI: 1.0-1.16, P = .0456), diabetes (OR 12.70, 95% CI: 1.24-130.3, P = .0324), and isolated medial NC facet arthrodesis (OR 17.48, 95% CI: 3.23-94.54, P = .0009) were significantly associated with nonunion. No significant association with nonunion was identified based on the type of bone graft, fixation construct, or whether concurrent arthrodesis of adjacent foot joints was performed.Conclusion: This study demonstrates a significant rate of nonunion following NC joint arthrodesis, exceeding that previously reported. We found that the rate of nonunion significantly increased in arthrodeses involving only the medial NC facet as compared to those including multiple NC facets.