Risk factors for poorly controlled and recurrence-prone ingrown toenails treated with nail braces: A retrospective observational study of 238 cases

Background: Nail braces are reportedly effective for treating both acute inflamed and chronic dystrophic type ingrown toenails. Aims: In this study, risk factors for poorly controlled and recurrence-prone ingrown toenails treated with nail braces were identified. Methods: We performed a retrospective study on patients with ingrown toenails between June 1, 2015, and May 31, 2018. The last follow-up date was January 31, 2019. Multivariate logistic regression was performed to evaluate the possible factors associated with poorly controlled status (ongoing paronychia during treatment) and recurrence. Results: There were 120 (244 sides) and 118 patients (167 sides) with chronic dystrophic and acute inflamed type ingrown toenails, respectively. The mean treatment duration and follow-up period were 161.2 ± 98.3 days and 432.7 ± 320.9 days, respectively. Poor control and recurrence were seen in 7.3% (17/232) and 12.2% (27/221) of the patients, respectively. In the multivariate analysis, acute inflamed ingrown toenails, previous nail avulsion, proximal nail fold hypertrophy and more than one affected side remained significantly associated with poorly controlled ingrown toenails. Foot bone deformity was significantly associated with recurrence. Limitations: This study was a retrospective study so that confounding factors such as comorbidities, body mass index, accompanying nail changes and lifestyle could not be evaluated. Conclusion: Several risk factors related to poor control and recurrence were identified. Patients could therefore benefit from more suitable treatment plans with reasonable expectation.