decision of the PI

Chronic sacrococcygeal pilonidal disease is a common acquired condition associated with hirsutism that predominantly affects young male patients. Morbidity from this disease results in pain, embarrassment and loss of normal activities, causing absenteeism from work and school.

Various surgical procedures have been described for the treatment of both primary and recurrent pilonidal disease counting: open excision and healing by secondary intention, marsupialization, excision and primary closure (midline or off-midline), excision and repair by flap.

No single method has been accepted as the "gold standard", and none of them cancels the risk of recurrence.

The optimal therapy for pilonidal sinus disease should be simple, with good aesthetic outcomes and a low recurrence rate. It must allow the return to normal activities quickly.

The parasacral perforator flap seems to answer these entire requirements. No study compares this flap repair with the most common procedure, which is the open excision with secondary healing. The aim of this study is to assess the efficacy and the security of the reconstruction of the natal cleft with the perforator parasacral flap versus open excision with secondary healing in the treatment of sacrococcygeal pilonidal sinus.

Many studies seem to attest the superiority of excision and reconstruction of the natal cleft with a flap rather than the open excision with secondary healing. Jamal et al. found a significantly lower recurrence rate with a rhomboid excision and reconstruction with a Limberg flap versus open excision and secondary healing (p=0.005) in a prospective controlled randomized trial including 49 patients. Keshuari et al. obtained the same significant results in their prospective controlled randomized study including 321 patients, with a rate of 1.2% of recurrence in the Karidakis flap repair cluster versus 7.5% in the excision with healing by secondary intention cluster. The time for complete wound healing was also significantly amended .

The reconstruction of the natal cleft with a Karydakis or Limberg flap seemed to be superior in terms of recurrence compared to open excision. But those flaps led to a significant and discernable scar.

The parasacral perforator flap has been described by Garrido et al. in 2002. It appears to be a good alternative, offering all the benefits of the reconstruction of the natal cleft in terms of lower rate of recurrence and lower time for complete wound healing. It also gives a better aesthetic result.

In this trial, patients will be operated under general anesthesia. A Methylene blue injection will identify the limits of the pilonidal sinus. An excision of the whole width of the relevant area will be performed, with depth reaching the presacral fascia. In the A group, a parasacral perforator flap repair of the natal clef will be done, and in the B group healing by secondary intention by dressing will be performed. Patients will be followed in consultation at 15 days, 3 months, 6 months, 1 year and 2 years.

During these visits, a potential clinical recurrence will be detected, the time to be completely healing will be evaluated, the period of loss of normal activities will be noted, the quality of life will be assessed by a standardized generic measure (EQ-5D-5L) and by a specific score (DLQI), and post-operative complications will be collected.

The aim of this study is to assess the efficacy and the security of the reconstruction of the natal cleft with the perforator parasacral flap versus open excision with secondary healing in the treatment of sacrococcygeal pilonidal sinus.

A medico-economic analysis evaluating the incremental cost-effectiveness and cost-utility ratio will be also done at 2 years. Additionally, an evaluation of the production costs of the new strategy (i.e. parasacral perforator flap) will be performed from the specific perspective of hospitals.

Inclusion Criteria:

• Patient with primary or recurrent sacrococcygeal pilonidal sinus disease,
• Minimum delay of 1 month after an infection of the pilonidal areas,

Exclusion Criteria:

• Florid abcess in the pilonidal sinus,
• Impossibility of general anesthesia, allergy to methylene blue, anticoagulant therapy,