Hidradenitis Suppurativa (HS) is a recurrent inflammatory disease (< 2 episode /6 months) with 1%-4% prevalence in Europe. Suppurating lesions are painful and involve one or more regions (axilla, genitofemoral, perineum, gluteal areas and inframammary, creases).

For recalcitrant stage II and III, wide surgical skin excision is the only recommended and validated treatment in case inefficacity of medical conventional systemic therapies or limited-local surgery.

Perforator Flaps (PF) surgery, are a new and innovative surgical technique, that, unlike secondary wound healing, allows a single stage reconstruction at the same time as skin excision without its disadvantages.: prolonged healing time, with multiple painful dressings (costs) retractile scar with reduction of the range of motion, dyschromia, unstable and fragile scar.

The hypothesis of study is a 30% reduction of time to healing by using perforators flaps technique (PF) versus wound healing (SIWH), for axillary reconstruction after surgical wide excision in axillary hidradenitis suppurativa stage II or III in adults with inadequate response to conventional systemic therapy.

This study is designed as an open randomized clinical trial comparing the efficacy of perforators flaps technique (PF) to decrease the healing time, versus secondary intention wound healing (SIWH) after skin excision for axillary Hidradenitis suppurativa.

This study involves 8 centers (2 closed) plastic surgery

Patients will be randomized by the investigator after inclusion using a Case Report Form (e-CRF) CleanWeb, Telemedecin Technologies, S.A.S). Randomization will be stratified on center and on laterality (unilateral/bilateral); in case of bilateral axillary HS, side will be randomly assigned at the same time than surgery group.

Centralized blocked randomization according to a 1:1 ratio will be prepared by the Clinical Research Unit (URC-EST).

Primary endpoint

Healing time defined as :

1. In SIWH group: time between the excisional surgery and total re-epithelialization (100%), treatment of potential wound healing delay related to complications included.
2. in PF group : time between the excisional surgery and the day of last stiches removal(closed incision), treatment of potential delay related to complications included .If partial necrosis< 50 %, occurs and is treated by SIWH , the secondary end point will be the total re-epithelialization.

If healing is not attended at the end of follow up, healing duration will be set at 6 months in both group

Secondary endpoints

To compare between groups:

• Recurrence rate during a follow-up of 12 months: new signs of disease in the axilla despite surgical treatment and Hurley staging of the involved axilla .
• Disabilities of the Arm, Shoulder and Hand score (DASH) and of the measurement of the amplitude of arm abduction using a goniometer : differences between inclusion and M3, M6, M12.
• Length of stay at the hospital at the discharge
• Time from surgery to return to daily activity
• Quality of life between inclusion and at M3, M6, M12; with MOS-SF36 / Dermatology Life Quality Index (DLQI)/ EQ 5D
• Aesthetic outcomes: VAS (1: worst aesthetic result-10 : best aesthetic result) obtained after submission of the pre/post-operative pictures of the axillary region to a medical/paramedical panel at M12 and patient satisfaction for the aesthetic outcomes at M12 with the same scale, Pre/post-operative pictures of the axillary region will be submitted to a medical/paramedical panel and measured with the same Visual Analogic scale (VAS) aesthetic outcomes 3 Pictures
• 1 face Arm elevated with the 2 axillae in the frame, 1 of the axillae face, 1 of the axillae profil
• The day of the surgery or one day before surgery: a picture to determine the size of the lesion (arm 90°) and with the size of the defect (Ruler or dimension written on the skin) after skin excision.

VAS patient satisfaction for the aesthetic outcomes

• Complication rates during a follow up of 3 months: hematoma, infection, cutaneous necrosis
• Pain (Visual Analogic Scale): before patient discharge, every 15 days until wound healing and at M3 and M6.
• Production costs of the new technique perforator flap from the hospital perspective
• Total average cost and incremental cost-utility ratio

Inclusion Criteria:

• Age ≥ 18 years and ≤ 70 years
• Reproductive age patient with an effective contraception
• Patient with a previously diagnosed of axillary HS (defined by European S1 guidelines) Hurley Grade II or grade III and send by dermatologist for wide excision surgery, because of inefficacy, or insufficient response or failure (recurrence or resistance) of previous medical conventional systemic treatments or limited surgery
• Minimum delay of 1 month after an inflammatory phase of axillary HS treated medically
• Patient candidate for excision surface of the axillary region representing a minimum excision area of 6 (major axis) / 6 (minor axis) or 28.5 cm2 (ellipse surface recall = half of major axis X half of minor axis X π, in this case = 3 X 3 X π)
• Patient with health insurance (AME excepted)
• Signed written informed consent

Exclusion Criteria:

• Contra indication to general anesthesia, allergy to methylene blue (mandated for the excisional surgery)
• Pregnancy woman (confirmed by a urine test beta-HCG) or breastfeeding woman
• Patient already included in the study
• Participation in any other interventional study or in the exclusion period any other interventional study
• Contra indication to perforator flaps/wide excision : to general anesthesia (ASA < IV Score Health Status), severe platelet disorders or patient at high risk of bleeding
• Acute superinfection grade ≥ 4 according to CTCAE in progress or diagnosed for less than 1 month
• Patient under legal protection measure and or deprived of freedom
• Patient unable to consent