Off-Midline Flaps Lower Recurrence in Pilonidal Surgery

Key Takeaways

• In a 2,222-patient cohort from a tertiary university hospital in Istanbul, Turkey, 5-year cumulative recurrence after surgery for primary pilonidal sinus disease was 7.9% and postoperative wound infection was 6.9%.
• In the study’s full results, fasciocutaneous elliptic rotation flap had the lowest reported 5-year cumulative recurrence at 0.0%, followed by Karydakis flap (1.5%), Bascom cleft lift (2.3%), and Dufourmentel flap (2.4%); lay-open treatment and midline primary closure had the highest recurrence at 19% and 18.6%.
• Most recurrences clustered within the first 2 years after surgery, and recurrence beyond 5 years was uncommon at 2.3%.
• Recurrence and postoperative wound infection differed significantly across techniques, and higher BMI and current smoking were associated with greater recurrence risk.

Primary pilonidal sinus disease is common in young adults, but long-term comparisons across operations can be hard to interpret when recurrence is time-dependent and follow-up windows differ. Early wound complications can further complicate those comparisons when they are not separated from later disease return after healing. This surgical question led investigators to compare nine techniques with fixed long-term follow-up and parallel tracking of postoperative infection.

At a single tertiary university hospital in Istanbul, Turkey, the Tokocin et al. International Wound Journal cohort study of nine operations retrospectively covered January 2006 through December 2020. Investigators screened 2867 surgeries and included 2222 patients with primary disease and at least 5 years of follow-up after excluding recurrent presentations, shorter follow-up, and incomplete records. Procedures included midline primary closure, lay-open treatment, Karydakis flap, Bascom cleft lift, Limberg flap, Dufourmentel flap, fasciocutaneous elliptic rotation flap, V-Y advancement flap, and Z-plasty. Primary outcomes were recurrence after complete wound healing and postoperative wound infection within 30 days, with Kaplan-Meier estimates at 2 and 5 years and multivariable Cox regression using lay-open treatment as the reference.

Overall recurrence was 10.2% (226/2222), 5-year cumulative recurrence was 7.9% (175/2222), and postoperative wound infection was 6.9% (154/2222). The lowest 5-year recurrence was reported with fasciocutaneous elliptic rotation flap and several off-midline flaps, whereas lay-open treatment, midline primary closure, and Z-plasty had the highest recurrence; both recurrence and infection differed significantly across techniques. Most recurrences occurred within 2 years, and median time to recurrence was 20 months (interquartile range [IQR] 12–36). Versus lay-open treatment, the hazard ratio (HR) for recurrence was 0.19 with Karydakis flap (95% confidence interval [CI] 0.12–0.30), 0.25 with Bascom cleft lift (95% CI 0.14–0.43), 0.26 with Dufourmentel flap (95% CI 0.12–0.57), and 1.65 with midline primary closure (95% CI 1.18–2.30); higher body mass index (BMI) and current smoking were also independently associated with recurrence, with smoking at HR 1.98 (95% CI 1.54–2.55).

This retrospective single-center analysis reflects institutional practice as well as procedure choice, because operating surgeons selected the technique and practice shifted over time, including discontinuation of midline primary closure after 2013. The cohort came from a high-volume unit and was predominantly male, which the authors said may limit generalizability beyond this Istanbul setting. The findings apply to primary pilonidal sinus disease and do not directly describe surgery for recurrent disease. Within those limits, the authors reported that off-midline flap procedures were associated with lower recurrence and infection in this cohort.

The authors concluded that off-midline flap techniques, especially Karydakis flap and Bascom cleft lift, were associated with more favorable long-term outcomes than midline primary closure or lay-open treatment in this Istanbul cohort. They also reported that predefined 2-year and 5-year recurrence estimates captured most recurrence events after surgery for primary pilonidal sinus disease.

Clinician Questions

Which patients do these pilonidal surgery findings apply to?

These findings apply to patients undergoing a first operation for primary pilonidal sinus disease at a single tertiary university hospital in Istanbul, Turkey, with recurrent disease excluded and at least 5 years of follow-up required; applicability to recurrent disease is not established by this cohort.

How was recurrence defined after surgery for primary pilonidal sinus disease?

Recurrence was defined as a new symptomatic sinus, abscess, or chronic discharge requiring intervention after confirmed complete wound healing, which separates recurrence from early wound problems and helps explain the fixed 2-year and 5-year recurrence estimates.

What operations were most often used when primary pilonidal sinus disease recurred?

Among patients who developed recurrence and underwent reoperation, Bascom cleft lift and Karydakis flap were the repeat procedures used most often, reflecting the reoperation pattern in this Istanbul cohort rather than a direct comparison of salvage surgery.