Impact of surgical case load on recurrence rates in pilonidal sinus disease: a cross-study data synthesis

A higher surgical caseload has been associated with better outcomes in various diseases. However, this relationship has not yet been studied for Pilonidal Sinus Disease (PSD). This study aimed to examine the impact of annual PSD surgery volumes on recurrence rates (RR).

A comparative cross-study data synthesis was conducted, including 1074 studies with 130,599 patients, focusing on PSD recurrence rates. Studies were categorized based on annual case load (ACL) into three groups: fewer than 10 operations per year (group 1), 10-30 operations per year (group 2), and 30 or more operations per year (group 3). Kaplan-Meier analyses were performed to evaluate recurrence rates, with additional stratification by study design (randomized controlled trial (RCT) or non-RCT) and surgical treatment type.

In randomized controlled trials (RCTs) of primary open treatment, group 1 (< 10 surgeries/year) had a 5-year recurrence rate of 23.5%, while group 2 (10-30 surgeries/year) had a rate of 12.5% (p < 0.0001). No data was available for group 3. For primary midline closure (pmc), the 5-year recurrence rates were 14.8% for group 1, 26.3% for group 2, and 12.8% for group 3. Non-RCT studies generally showed decreasing recurrence rates with higher surgical caseloads for most treatment types. However, midline closure surgery showed no significant improvement in recurrence rates with increased caseloads.

The study demonstrates that higher surgical caseloads significantly reduce PSD recurrence rates, with notable benefits observed for centers treating 30 or more patients annually. Specialization in high-volume centers may lead to improved outcomes for PSD, particularly in flap surgeries. However, midline closure surgery continues to show persistently high recurrence rates, regardless of caseload.