No clear benefit was shown for open healing over surgical closure. A clear benefit was shown in favour of off-midline rather than midline wound closure. When closure of pilonidal sinuses is the desired surgical option, off-midline closure should be the standard management.
Treatment of chronic pilonidal sinus with local anaesthesia: a randomized trial of closed compared with open technique.
To compare open with closed treatment of chronic pilonidal sinus.
                From 1993 to 1996, 100 patients were submitted to excision of chronic pilonidal sinus, with local anaesthesia and were randomized in two groups: group A in which open treatment and group B in which direct suture were performed. The follow-up, ranging from 37 to 89 months, was performed by outpatient visits or by phone.
                Short-term results showed 6 (12.0%) post-operative complications in group A vs 10 (20.0%) in group B. Long-term results showed 9 (18.0%) complications in group A vs 7 (14.0%) in group B. Mean wound healing was 58 days (range: 29-93) in group A vs 12 (range: 9-61) in group B. The return to normal activity was 25.7 (range: 11-77) vs 10.4 (range: 5-32). Wound healing and the return to normal activity were the only statistically significant differences.
                Regarding morbidity neither technique has particular advantages over the other. The closed technique produced quicker wound healing and a quicker return to normal activity.