Influence of failure of primary wound healing on subsequent recurrence of pilonidal sinus. combined prospective study and randomised controlled trial.

Objective: To find out whether failure of primary wound healing after excision and primary suture for chronic pilonidal sinus predicts recurrence.

Design: Follow-up of one prospective study and one subsequent randomised, multicentre study.

Setting: Three teaching hospitals in WesternNorway.

Subjects: A total of 197 consecutive patients operated on for chronic pilonidal sinus.

Interventions: Fifty two patients in the prospective group were given cloxacillin perioperatively. In the randomised study, 145 patients were randomised to have either a single preoperative dose of cefoxitin 2 g intravenously (n = 73) or no prophylaxis (n = 72). Patients were followed up for a median of 7 years.

Main outcome measures: Recurrence of pilonidal sinus.

Results: In the prospective group there were 10 recurrences (19%). In the randomised study 6 patients (8%) who had been given antibiotic prophylaxis had a recurrence compared with 14 patients (19%) who had not been given prophylaxis (p = 0.09). In both groups, failure of primary normal healing was significantly associated with early recurrence (p = 0.0002). Neither the use of antibiotics nor sex had any significant influence on the incidence of recurrences. Most recurrences occurred within the first year.

Conclusion: Wound complications significantly influenced the recurrence rate whereas antibiotics did not. Most recurrences were seen early.