SUPERIOR AND INFERIOR GLUTEAL ARTERY PERFORATORFLAPS IN RECONSTRUCTION OF GLUTEAL AND PERIANAL/PERINEAL HIDRADENITIS SUPPURATIVA LESIONS

CIGDEM UNAL, M.D.,1* OKTAY AHMET YIRMIBESOGLU, M.D.,2 JALE OZDEMIR, M.D.,1 and MUSTAFA HASDEMIR, M.D.1

Background: Hidradenitis suppurativa is a debilitating disease with a tendency to form abscesses, sinus tracts, and scar formation. In thisreport, our experience with reconstruction of hidradenitis lesions of the gluteal and perianal/perineal area using superior and inferior glutealartery perforator flaps (SGAP and IGAP) are discussed. Patients: A prospective study was conducted in collaboration with the general sur-gery department for patients with gluteal and perianal/perineal hidradenitis suppurativa between December 2005 and May 2010. Data ofeach patient included age, sex, disease localization, duration of symptoms, comorbidities, size of defect after excision, perforator flap cho-sen, complications, and postoperative follow-up. Results: Eleven SGAP and six IGAP flaps were used in 12 patients with gluteal and peria-nal/perineal involvement. There was one flap necrosis for whom delayed skin grafting was performed. The mean follow-up period was 20months without recurrences. Conclusion: Patients with gluteal and perineal/perianal hidradenitis suppurativa are usually neglected by sur-geons because of lack of collaboration of general and plastic surgery departments. Most surgical treatment options described in the litera-ture such as secondary healing after excision and skin grafting prevent patients from returning to daily life early, and cause additional mor-bidities. Fasciocutaneous flaps other than perforator flaps may be limited by design such that both gluteal regions may have to be used forreconstruction of large defects. SGAP and IGAP flaps have long pedicles with a wide arc of rotation. Large defects can be reconstructedwith single propeller flap designs, enabling preservation of the rest of the perforators of the gluteal region. VVC 2011 Wiley-Liss, Inc. Micro-surgery 31:539–544, 2011.

Hidradenitis suppurativa is a chronically relapsing

inflammatory disease of the skin and subcutaneous tis-

sues.1 It is characterized by painful abscesses, multiple

and odiferous draining sinus tracts, and chronic fibrosis

with scar formation leading to limitations in range of

motion of the involved area.2 Though it can be seen any-

where on the body, most frequently affected sites are

axilla, inguinal, perianal, perineal, inframammary, buttock

and pubic region, chest, scalp, retroauricular area, and

eyelid.3

Although hidradenitis suppurativa was first described

by Velpeau in 1839, it was not until the begining of

20th century that Schiefferdecker has reported the asso-

ciation of this disease with apocrine sweat glands.2

Studies have failed to prove that the epithelium formed

in the sinuses of the lesions are derived from either the

apokrin glands or the hair follicles.4 It is for sure that

the initial folliculitis leads to abscesses causing chronic

disseminating infections in the subcutaneous plane and

thus has a significant negative impact on the quality of

patient’s life.5

None of the medical treatment options have proven to

be curative in hidradenitis suppurativa patients. Surgical

resection of the affected tissues is the only curative treat-

ment. In the current medical literature, various techniques

are described to reconstruct wide defects of gluteal and

perianal/perineal areas. They are split thickness skin

grafts, fasciocutaneus flaps other than perforator flaps,

and leaving tissues for secondary granulation.2,6,7 Recon-

struction techniques mentioned usually do not completely

fulfill the expectations of the patient or the reconstructive

surgeon. Skin grafts unfortunately do not provide enough

cushion on these areas, and it takes a long time for the

patients to return to normal daily life. Although flaps

described for reconstruction of hidradenitis suppurativa

defects of the gluteal region such as gluteal thigh flap,

gluteal rotation or advancement flap, and medial thigh

flaps have some advantages compared with skin grafts,

limitations in terms of design and size of flaps are the

faced difficulties.7 Long pedicles of superior and inferior

gluteal artery perforator flaps (SGAP and IGAP) enable

healthy tissue mobilization up to 12 cm in distance; thus

prevent restrictions of other defined flaps for hidradenitits

suppurativa defects.8

The purpose of this report is to present the use of

SGAP and IGAP in gluteal, and perianal/perineal hidrade-

nitis suppurativa patients, and to show postoperative

long-term results.

PATIENTS AND METHODS

Patients with gluteal and perianal/perineal hidradenitis

suppurativa admitted to Kocaeli University Hospital

between December 2005 and May 2010 were evaluated

by both Plastic, Reconstructive and Aesthetic Surgery

and General Surgery Departments. The diagnosis of

hidradenitis suppurativa was confirmed by history and

1Plastic Reconstructive and Aesthetic Surgery Department, Kocaeli Univer-sity Medical Faculty, Umuttepe, Izmit, Turkey2General Surgery Department, Kocaeli University Medical Faculty, Umuttepe,Izmit, Turkey

*Correspondence to: Cigdem Unal, M.D., Plastic Reconstructive and Aes-thetic Surgery Department, Kocaeli University Medical Faculty, Umuttepe41400, Izmit, Turkey. E-mail: cigdem_unal_75@hotmail.com

Received 25 December 2010; Accepted 22 April 2011

Published online 23 August 2011 in Wiley Online Library (wileyonlinelibrary.com).DOI 10.1002/micr.20918

VVC 2011 Wiley-Liss, Inc.

physical examination at the time of first consultation.

Only patients with gluteal and perineal/perineal region

involvement were included in this study. Formerly oper-

ated patients and hidradenitis suppurativa patients other

than gluteal or perianal/perineal region were excluded.

All patients with gluteal or perianal/perineal region

were admitted to the hospital 1 day prior to surgery and

were administered oral sodium phosphate products for

bowel cleansing.

SURGICAL TECHNIQUE

Perforators of the gluteal region were marked with an

8 MHz hand Doppler under general anesthesia, with the

patient in supine position with a 458 angle between the

thigh and trunk. Radical excision of the lesions including

the gluteal fascia was the standardized procedure. Peria-

nal area excision and anal sphincter evaluation was car-

ried out by the same general surgeon. The decision of the

appropriate perforator for reconstruction and design of

the flap were planned after excision of the lesion, taking

into account the arc of rotation of the pedicle during ad-

aptation.

The perforator(s) of the flap were followed to the

source vessel by intramuscular dissection in three cases,

until the sacral fascia in the rest. To achieve a wider arc

of rotation for the flap when necessary, the perforator fur-

thest from the lesion was preferred, and the rest were

clipped.

The flaps were named according to the perforator

localization. Those perforators that were located along

the line drawn from the posterior superior iliac spine to

the greater trochanter were named ‘‘superior gluteal artery

perforators.’’8 For inferior gluteal artery perforators, the

landmarks were the line drawn from the greater trochan-

ter to the middle of the distance between the posterior

superior iliac spine and medial border of the gluteal

crease. Those perforators which were chosen during sur-

gery were named ‘‘inferior gluteal artery perforators.’’8

Our prophylactic and theuropathic antibiotic medica-

tion were suggested by our hospital Infection Commitee,

preoperative prophylaxis with first generation cephalospo-

rins was started to all patients and continued for 5 days

postoperatively. The patients were immobilized for 3

days after surgery. A soft diet was prescribed during hos-

pitalization period. An antidiarrheal drug containing

diphenoxylate and atropine were given orally to patients

for 5 days to inhibit fecal contamination of reconstructed

areas. The drains were removed on the 3rd or 4th day

postoperatively, when the drainage was below 20 cc/day.

The patients were discharged after full mobilization.

The recorded data for each patient included age, sex,

anatomic localization of disease, duration of symptoms,

comorbidities, size of defect after radical excision, perfo-

rator flap chosen for reconstruction, complications, and

postoperative follow-up.

RESULTS

Twelve patients with severe chronic hidradenitis sup-

purativa of gluteal and perianal region were treated. All

were male with age range of 24–56 (mean 44.4 years).

The mean duration of symptoms of patients at their

admission was 16 years (5–31 years). Four patients were

smokers. They all received symptomatic medical treat-

ment such as broad spectrum antibiotics and ‘‘abscess

drainage’’ more than once during recurrent inflammatory

phases.

Seven of the 12 patients had perianal/perineal

involvement as well as gluteal skin. Two of the patients

had lesions on both infragluteal fold. The rest of the three

patients had gluteal skin involvement. One patient who

had lesions completely surrounding the anal area needed

diverting loop colostomy. Size of skin defect after exci-

sion of lesions ranged from 7 3 9 cm to 23 3 40 cm

(mean 13 3 19 cm). The defects formed after radical

excision were repaired with SGAP flaps in eight patients.

A total of 11 SGAP flaps were performed, three of which

were bilateral. Only three of the SGAP flaps were

advancement type and eight of them were propeller flaps.

Six IGAP flaps were used in four patients, two being

bilateral. Four of these flaps were advancement flaps and

two were propeller flaps (Table 1).

There was one suture detachment in one patient that

needed secondary revision. One SGAP flap failed because

of hematoma formation and venous congestion. The

defect was grafted with a split thickness skin graft. The

mean hospitalization time for patients was 6 days (range

3–10 days). The mean postoperative follow-up period

was 20 months (range 8–36 months). There was no recur-

rence of hidradenitis suppurativa lesions in any of the

patients during the course of follow-up period. (The rep-

resentative cases are shown in Figs. 1 and 2.)

DISCUSSION

Hidradenitis suppurativa classically starts as an infun-

dibulofolliculitis that leads to perifollicular apocrine and

eccrine gland inflammation.9 Follicular rupture causes

formation of an abscess by releasing keratin and bacteria

into the surrounding dermis. Although no bacteria is

found in the initial stages of the disease, coagulase nega-

tive Staphilococcus aureus, Streptococcus milleri, and

Chlamydia trachomatis are often seen in cultures during

the late stages of the disease.9 Superficial sampling is

frequently sterile or finds bacteria from normal flora.

Deep sampling is difficult and may be contaminated by

superficial flora. It is therefore impossible to rely on cul-

turing lesions to adapt antibiotic treatment.9 Therefore,

540 Unal et al.

Microsurgery DOI 10.1002/micr

first generation cephalosporins that are effective against

S. aureus and Streptococcus species were the drug of

choice for profilaxis during preoperative and postopera-

tive period.

Medical management of this disease consists of topi-

cal and systemic antibiotics, antiandrogen therapy, hor-

monal therapies, isoretinoin, steroids, and tumor necrosis

factor a blockers.1,10–13 Seventy-five percent of the

patients remain in stage 1 according to Hurley’s Criteria;

where abscess formation leads to scarring without sinus

tracts.14 These patients are generally treated by dermatol-

ogists or general surgeons. The ones consulted to plastic

surgeons are those who are in stage 2 or 3 of the disease

with diffuse involvement or multiple interconnected

tracts, and abscesses. They need soft tissue reconstruction

after radical surgical resection. All the patients in our se-

ries consisted of stage 3 patients as well.

Recurrence rates of hidradenitis suppurativa differ in

the literature according to localization of the disease.15

The largest surgical survey of hidradenitis suppurativa

reports the following rates of recurrence in 82 patients

treated with 118 radical excisions: axillary, 3%; perianal,

0%; inguinoperineal, 37%; and submammary, 50%.16

According to Harrison et al.,16 recurrences occurred

within 3–72 months following surgery, and they were

either from inadequate excision or (as in the case of

submammary recurrence) an unusually wide distribution

of apocrine glands. Kagan et al.2 have reported that they

did not have any recurrences in their series of 57

patients with hidradenitis suppurativa. Their series con-

sisted of patients with different stages of hidradenitis

suppurativa localized in axilla, inguinoperineal area, or

buttocks. One of the main reports in the literature about

the recurrence rate of the gluteal region is Balik

et al.’s.17 In this report, wounds were left open for sec-

ondary healing in majority of the patients and in the

rest, skin grafting or primary closure was performed. No

recurrences were seen in their 5-year follow-up period,

and they concluded that recurrences seen in hidradenitis

suppurativa were the result of incomplete excisions. We

believe that in our cases, complete excision of all lesion

bearing areas including the gluteal fascia led to a mean

duration of 20 months recurrence-free follow-up period.

Other factors effecting recurrence are continuous evolu-

tion of the lesion and age of the patient. Operating

patients with lesions in the evolution phase result in

high rates of recurrence. On the other hand, rates are

lower with older age.18 None of our patients had lesions

in evolution phase, and 8 out of 12 patients were 35

years of age or older. These may be additional reasons

for no recurrence.

Although surgical management of patients with axil-

lary involvement is commonly discussed in the literature,4

those with gluteal and perianal/perineal involvement are

rarely discussed. Patients with gluteal and perianal/peri-

neal lesions usually apply to general surgery outpatient

Table 1. Details of Patients with Gluteal and Perianal/Perineal Hidradenitis Suppurativa

Case

Gender,

age

Duration

of illness

(years) Site of lesion

Size of

defect after

resection (cm)

Perforator

flap used in

reconstruction Complications

Postoperative

follow-up

(months) Comorbidities

Patient

satisfaction

1 M, 44 23 R&L glutea,

perianal

25 3 15 SGAP (bilateral) 36 Smoker Excellent

2 M, 55 17 R&L infragluteal

fold

16 3 8 (R) IGAP desc br

perforator flap

(bilateral)

24 Smoker Excellent

8 3 7 (L)

3 M, 50 21 R&L glutea,

perianal

12 3 18 (R) SGAP (bilateral) 30 Good

20 3 30 (L)

4 M, 28 5 R&L infragluteal

fold

8 3 11 (R) IGAP (bilateral) 21 Excellent

7 3 9 (L)

5 M, 30 10 R gluteal,

perianal

16 3 17 SGAP Sutur

detachment

18 Smoker Excellent

6 M, 56 31 R&L gluteal,

perianal

24 3 27 SGAP (bilateral) 22 Excellent

7 M, 48 24 Intergluteal,

perianal

13 3 20 SGAP 20 Excellent

8 M, 39 16 R gluteal 10 3 16 IGAP 10 Excellent

9 M, 24 5 L gluteal 13 3 18 IGAP 13 Excellent

10 M, 47 23 R gluteal,

perianal, thigh

40 3 23 SGAP, STSG

(thigh)

Flap

necrosis

19 Smoker Good

11 M, 35 12 L gluteal 7 3 9 SGAP 8 Excellent

12 M, 29 7 R&L gluteal,

perianal

12 3 14 SGAP, excision

primary sutur

14 Excellent

R: right, L: left, SGAP: superior gluteal artery perforator, IGAP: inferior gluteal artery perforator, STSG: split thickness skin graft, Desc: descending, Br:branch.

Gluteal Hidradenitis Lesion Reconstruction 541

Microsurgery DOI 10.1002/micr

clinics. Management of these patients mainly depends on

the surgeon’s preference. Unroofing and exteriorization of

sinus tracts, and leaving the excised tissue to heal sec-

ondarily is commonly done surgical procedures.17 The

stage 3 lesions are mostly treated by leaving the excised

wound bed to heal secondarily, or they are skin grafted.

Balik et al.17 have reported a complete wound healing

time of 12.2 weeks when secondary healing was pre-

ferred. Methods based on skin grafting also require a

long healing time. They do not provide enough cushion,

and have unpleasant cosmetic appearance. There are few

reports concerning reconstruction in hidradenitis suppura-

tiva with different designs of fasciocutaneous flaps for

the gluteal region.2,7

Rotation V–Y advancement flap based on the first

perforator of the deep femoral artery has been used Kishi

et al.7 as a fasciocutaneous flap. However, according to

their experience, when the rotation arc of this flap was

restricted by skin or the first perforator, an island gluteal

thigh flap was necessary to move the flap further. Other

fasciocutaneous flaps such as the medial thigh flap can be

used to cover the perianal/perineal area. Unfortunately,

because they are based on the femoral system, they may

be restricted by adequate length to reach the most distal

parts of the perineal/perianal defects.7 To overcome the

restriction of inadequate mobilization of flaps of the glu-

teal and posterior thigh region other than perforator flaps,

we have advocated using SGAP and IGAP to cover the

defects formed after resection of hidradenitis suppurativa

lesions.

Although perforator flaps have been used as a first

choice in many reconstructive procedures, lack of collab-

oration between plastic surgeons and general surgeons

has decreased the possibility of using perforator flaps as

a surgical treatment in patients with hidradenitis suppura-

tiva. Optimal results can be obtained by perforators flaps

because of the fact that superior and inferior gluteal ar-

tery perforators are abundant, and they can provide pedi-

cle lengths up to 10–12 cm.8 Ahmadzadeh et al.8 have

demonstrated in their cadaveric study that each perforator

of superior gluteal artery supplies an area of 21 6 8 cm2,

and each perforator of the inferior gluteal artery supplies

an area of 24 6 13 cm2. On average, they have found 5

6 2 perforators of the superior gluteal artery and 8 6 4

of the inferior gluteal artery on each side of the gluteal

region. In our series, we were able to find at least one

perforator on the disease-free areas of gluteal region to

raise flaps.

SGAP and IGAP flaps have been shown to be used as

pedicled and free flaps. They have gained popularity as

an alternative to deep inferior epigastric flap in autolo-

gous breast reconstruction.19,20 Pedicled gluteal artery

perforator flaps have been described for reconstruction of

sacral and ischial pressure sores,21,22 lumbosacral

Figure 1. a: Forty-eight-year-old patient with hidradenitis suppurativa lesions in the intergluteal area and left buttock. Perforators of the

SGAP flap were marked on the left gluteal area (case 7). b: A 13 3 20 cm2 defect was formed after complete excision. c: The SGAP flap

was raised based on two perforators. Dissection of the perforators until the sacral fascia allowed an �10–12 cm of pedicle length.

d: Result at postoperative 12 months. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary. com.]

542 Unal et al.

Microsurgery DOI 10.1002/micr

defects.23 Wagstaff et al.24 have used gluteal perforator

flaps in perineal and vaginal reconstruction successfully.

When compared with skin grafts and secondary heal-

ing of tissues, an important advantage of reconstruction

with perforator or any other flap surgery in hidradenitis

suppurativa patients with gluteal or perianal/perineal

involvement is the early mobilization period. The average

hospital stay of our patients was 6 days. They were

allowed to take a shower at postoperative day 10, which

may be troublesome in skin grafted patients or for those

whose wounds are left for secondary healing. Though

flaps other than perforator flaps can be used in recon-

struction of defects formed after excision of hidradenitis

suppurativa lesions, pedicles of rotation or transposition

flaps may cause restrictions in reaching distal parts of the

defects.7 This disadvantage can be overcome using perfo-

rator flaps. Intramuscular dissection of the perforator

allows pedicle lengths of up to 12 cm.8 They can be used

as propeller flaps, designed such that adjacent perforators

of the same region can be used in the future, if neces-

sary. They can also be tailored according to the shape of

the defect. These are the major advantages of perforator

flaps compared with other reconstructive options.

CONCLUSIONS

This paper describes surgical treatment options of glu-

teal and perianal/perineal hidradenitis suppurativa lesions

with SGAP and IGAP flaps. Superior part of the perianal

defects are easily reconstructed with SGAP flaps, whereas

lower part of the anal area and perineum is frequently

preferred to be reconstructed with IGAP flaps. For one-

sided lesions, the ipsilateral SGAP or IGAP designed like

a propeller flap gives good cosmetic results in terms of

donor site scars. Long pedicles of gluteal perforator flaps

provide a wide arc of rotation that enables local recon-

struction; thus, large defects can be reconstructed with

single propeller flap designs that can be tailored accord-

ing to the defect. Other perforators of the region can be

spared for future use, if necessary.

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