Healing by Primary versus Secondary Intention after Surgical Treatment for Pilonidal Sinus

Background

Pilonidal sinus arises in the hair follicles in the buttock cleft. The estimated incidence is 26 per 100,000, people, affecting men twice as often as women. These chronic discharging wounds cause pain and impact upon quality of life. Surgical strategies center on excision of the sinus tracts followed by primary closure and healing by primary intention or leaving the wound open to heal by secondary intention. There is uncertainty as to whether open or closed surgical management is more effective.

Objectives

To determine the relative effects of open compared with closed surgical treatment for pilonidal sinus on the outcomes of time to healing, infection, and recurrence rate.

Search Methods

For this first update we searched the Wounds Group Specialised Register (24/9/09), the Cochrane Central Register of Controlled Trials (CENTRAL), the Cochrane Library (Issue 3, 2009), Ovid MEDLINE (1950, September, Week 3, 2009), Ovid MEDLINE(R) In-Process and Other Non-Indexed Citations (September 24, 2009), Ovid EMBASE (1980–2009, Week 38), and EBSCO CINAHL (1982, September Week 3, 2009).

<target id="page_151" target-type="page">151</target>Selection criteria

All randomized controlled trials (RCTs) comparing open with closed surgical treatment for pilonidal sinus. Exclusion criteria were non-RCTs, children aged younger than 14 years, and studies of pilonidal abscess.

Data collection and analysis

Data extraction and risk of bias assessment were conducted independently by three review authors (AA/IM/JB). Mean differences were used for continuous outcomes and relative risks with 95% confidence intervals (CI) for dichotomous outcomes.

Main Results

For this update, 8 additional trials were identified, giving a total of 26 included studies (n = 2530). Seventeen studies compared open wound healing with surgical closure. Healing times were faster after surgical closure compared with open healing. Surgical-site infection (SSI) rates did not differ between treatments; recurrence rates were lower in open healing than with primary closure (RR 0.60, 95% CI 0.42−0.87). Six studies compared surgical midline with off-midline closure. Healing times were faster after off-midline closure (MD 5.4 days, 95% CI 2.3−8.5). SSI rates were higher after midline closure (RR 3.72, 95% CI 1.86−7.42) and recurrence rates were higher after midline closure (Peto OR 4.54, 95% CI 2.30−8.96).

Conclusions

No clear benefit was shown for open healing over surgical closure. A clear benefit was shown in favor 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.