Optimization of surgical strategies and clinical efficacy analysis for infected classic preauricular fistula

This study evaluated the effects of surgical timing, microscope-assisted operation, and partial helix crus cartilage resection on operation duration, postoperative incision healing, recurrence rate, and scar formation in children with infected classic preauricular fistula, analyzed the clinical value of different surgical strategies for its standardized treatment, and ensured result reliability via rigorous control of selection and temporal confounding.

A retrospective analysis was performed on 74 children who underwent surgery for infected classic preauricular fistula, grouped by intraoperative infection status (early erythema-swelling, prolonged erythema-swelling, localized abscess), microscope application, and cartilage resection. Selection bias was controlled by baseline comparison; confounders (age, sex, infection severity) were adjusted via 1:1 propensity score matching (PSM) and multivariable regression. Group differences in key efficacy indicators were compared, with nonparametric tests for non-normally distributed data (median [IQR]). Post-hoc power analysis and learning curve analysis (study period: 2021-2023 [early], 2024-2025 [late]) were also conducted.

Baseline characteristics were comparable across all groups (P > 0.05). For surgical timing subgroups, recurrence rate and incision healing showed no intergroup differences (P > 0.05), but the localized abscess group had significantly longer operation duration (61.8 ± 8.8 min, median 62.0 [56.0-68.0] min) and lower scar scores (2.5 ± 0.6 points, median 2.0 [2.0-3.0] points) than the early (37.7 ± 4.9 min, median 38.0 [35.0-41.0] min) and prolonged erythema-swelling groups (42.7 ± 7.4 min, median 43.0 [38.0-47.0] min) (P < 0.05), with no significant difference in median [IQR] follow-up time (P > 0.05). Microscope application had no significant effects on all efficacy indicators (P > 0.05), with consistent results after PSM; follow-up time and recurrence rate also showed no intergroup differences (P > 0.05). The cartilage resection group had a significantly lower postoperative recurrence rate (1.75%, 1/57) than the non-resection group (17.65%, 3/17), with this difference remaining significant after multivariable regression (P < 0.05). Learning curve analysis revealed significantly shorter operation duration in the late study stage (59.2 ± 10.8 min) than the early stage (68.5 ± 12.3 min, P < 0.001), with no difference in recurrence rate (4.8% vs. 1.7%, P = 0.321). Post-hoc power analysis showed 72% power for detecting recurrence rate differences and 89% for operation duration differences. Subgroup analyses found no significant recurrence rate differences between non-abscess and abscess groups (2.0% vs. 4.5%, P = 0.432) or between different preoperative management groups (2.6% vs. 4.5%, P = 0.587).

For children with infected classic preauricular fistula, early infection stage before localized abscess formation is the recommended surgical timing, which shortens operation duration and improves scar satisfaction. Intraoperative partial helix crus cartilage resection effectively reduces postoperative recurrence risk, with strict control of resection range to preserve auricle morphology. Microscope-assisted operation has no obvious advantages in reducing recurrence or improving incision healing, and its clinical application can be individualized. This study is limited by small sample size, only 4 recurrence events in 74 patients leading to underpowered detection for the primary outcome (recurrence rate), and premature 3-month scar assessment prior to full scar maturation (6-12 months). The conclusions require verification via large-sample multicenter randomized controlled trials.