Background: It has long been suspected that acute infection leads to less satisfactory results in soft tissue surgery. Its influence on long-term recurrence rate in primary pilonidal sinus surgery has not been investigated yet.

Patients and Methods: 583 patients (military cohort) were analyzed, comparing an incision and drainage (I&D) group preceding surgery (n = 286 pts) with a spontaneous abscess and empyema rupture group (n = 297 pts). Long-term recurrence rate up to 25 years following surgery was determined.

Results: The I&D group achieved a 20 year recurrence rate of 24 %, whereas the non-I&D-group had 35 % recurrences (p = 0.0034). Analyzing the subgroup with primary open wound treatment (n = 349 pts), the I&D group did significantly better after 20 years (16 % actuarial recurrence rate versus 34 %; p = 0.009; log-rank-test).

Conclusions: Early I&D treatment preceding definite surgery for some weeks seem to give significant superior results compared to primary surgery without I&D. The combination of early I&D and asymmetric excision and out of the midline closure is expected to give even further improved results compared to this cohort. The optimum interval between I&D and definite surgery has still to be determined.