Evaluating Risk Factors for Surgical Site Occurrences: Infection and Wound Dehiscence Post Definitive Surgery for Sacrococcygeal Pilonidal Sinus Disease.

BACKGROUND

Sacrococcygeal pilonidal sinus disease (SPD) predominantly affects young adults and is associated with high morbidity after surgery. Surgical site infections (SSIs) and wound dehiscence (WD) are frequent and clinically significant complications. This study evaluated their rates and identified associated risk factors across multiple surgical techniques.

METHODS

A retrospective multi-centre cohort study was conducted across eight hospitals in Western Australia (2010-2019). Patients aged ≥15 years undergoing elective definitive SPD surgery with flap or secondary intention techniques were included. Data were extracted from medical records and electronic databases. SSI risk was analysed with univariate and multivariate logistic regression, while WD was examined using Cox proportional hazards modelling. Outcomes included 30-day re-presentation and readmission rates, with extended follow-up for recurrence.

RESULTS

A total of 774 patients were analysed. SSIs occurred in 28.8% and WD in 28.4%. The cohort included 79.7% male patients, with a mean age of 27.08 (SD±9.06) years and a BMI of 28.58 (SD±6.15).  Multivariate analysis demonstrated that secondary intention techniques (OR 6.0, p<0.01), other flap procedures (OR 3.1, p=0.03), overweight status (OR 1.9, p=0.01), and WD (OR 50.6, p<0.01) were independent risk factors for SSIs. In contrast, clear surgical margins and methylene blue use were protective. Cox regression showed increased WD risk with Karydakis flap (HR 1.8, p=0.04), modified Limberg flap (HR 2.0, p=0.03), and smoking (HR 1.4, p=0.04). Within 30 days, 27% re-presented and 7.5% were readmitted, mainly for SSIs or WD, with regional variation reflecting practice differences.

CONCLUSION

SSIs and WD remain common and burdensome after SPD surgery. The modified Karydakis flap demonstrated the most favourable risk profile. Optimising patient factors, meticulous surgical technique, and structured training are essential to reduce complications and improve outcomes.