Pilonidal Disease

1.    Introduction

Image courtesy of healthdirect Opens in new window

Pilonidal disease is a chronic skin Opens in new window infection which typically occurs as a cyst in the crease between the buttocks and often at the upper end. People with this condition have one or more cysts in that area that tend to get inflamed and infected. A pilonidal cyst may look like a small dimple (called a pit or sinus). Hair may stick out from it.

2.   Background and Incidence

Pilonidal disease, by definition, refers to a subcutaneous infection occurring in the upper half of the gluteal cleft. It may present as an acute pilonidal abscess with pain, erythema, and induration or as a pilonidal sinus, which is an indolent wound that is resistant to spontaneous healing, and can cause significant discomfort and drainage.

pilonidal disease is commonly found in young adults, and typically present in the second decade of life. Men are more frequently affected than women at a ratio of three or four to one, and is more commonly seen in individuals with more body hair.

It is not known to be more common in any one racial group; however, certain occupations such as the military, hairdressers, and sheepshearers have been associated with the development of pilonidal disease. Other predisposing factors to pilonidal disease have been suggested and include obesity, being a vehicle driver, a sedentary occupation, and having a history of a furuncle at another site on the body.

Others have implicated anatomic factors such as natal cleft as risk factors for pilonidal disease. In a study of 50 patients with pilonidal disease, the depth of natal cleft was compared to 51 volunteers. The report shows a significantly deeper natal cleft in the pilonidal disease group (27.1 vs 21.1 mm; p<0.01).

Although a genetic predisposition has not been determined, family history does seem to play a role in this disease process. A recent report indicates that a family history of pilonidal disease predisposes patients to earlier onset of the disease and higher long-term (25 years) recurrence rate of over 50%.

The incidence of pilonidal disease is not accurately known, but has been reported to affect up to 0.7% of adolescents and young adults and up to 8.8% of recruits in the Turkish army. Others have calculated the incidence of the disease at 26 per 100,000 persons regardless of age.

pilonidal disease first appeared in the medical literature in 1833 when William Mayo published his first descriptions of this problem. In 1880, Hodges introduced the term “pilonidal,” which means “hair nest.” The term pilonidal “cyst” is a misnomer, because no epithelialized wall exists in the cavities this disease creates. Pilonidal “sinus” or “disease” are the more accurate terms. Pilonidal disease itself, and the surgical and medical treatment related to it, can be a significant source of morbidity and disability. This disease disables patients primarily because of pain and its inconvenient location in the gluteal cleft.

Traditionally, treatment for pilonidal disease was wide local excision; however, in World War II entire hospital wards were filed with soldiers convalescing from these large excisional operations.

In fact, nearly 80,000 soldiers were hospitalized for an average of 55 days for wound healing. It became such a problem that the Surgeon General forbade wide local excision as primary therapy. Thus, World War II symbolizes a paradigm shift that occurred in favor of conservative management for pilonidal disease.

Much has evolved in the treatment of pilonidal disease and ranges from non-operative treatments such as shaving and hygiene to operative procedures ranging from excision to flap reconstruction.

Each has its role in treating this disease spectrum, and management of pilonidal disease should be tailored to the individual clinical presentation; however, no treatment has proved completely satisfactory. Treatment goals should be maintained and include the complete resolution of the pilonidal disease through methods that have low recurrence and low morbidity.

3.    Pathogenesis

The aetiology of pilonidal disease has been controversial, with initial beliefs tied to embryologic origins. Pilonidal disease was considered to be an inborn defect of the skin in the interguteal region secondary to a remnant of the medullary canal and infolding of the surface epithelium; however, empiric data currently supports this disease as being an acquired condition. First, the disease is not present at birth, but in young adults; second, it is more frequent in hirsute men; and third, certain occupations predispose people to develop pilonidal disease.

Pilonidal disease has been observed in the hands of barbers and sheep shearers, implying that shed hairs may initiate the condition.

The acquired theory of pilonidal disease is most popular, but the mechanism varies widely. This disease most likely results from problems that attack the epidermis in the gluteal cleft, rather than from a problem in the deep tissues.

Bascom believes that the skin in the natal cleft is normal; however, conditions may exist that predispose a patient to pilonidal disease. Bascom believes that hair follicles in the natal cleft become distended with keratin and then infected, forming an abscess that eventually ruptures into the subcutaneous tissue. Vacuum forces and negative suction in the natal cleft draws hair and debris into the midline pits of the hair follicle then into the abscess cavity (pilonidal abscess).

Karydakis proposed that hair with chisel-like roots inserts itself into the natal cleft leading to foreign body tissue reaction and infection. Both theories seems plausible as pilonidal lesions have the pathologic characteristics of a foreign body reaction, presumably from burrowed or subcutaneously displaced hair and epithelial debris; however, no published study exist which directly prove or refute the current theories about how pilonidal disease occurs.

Certain anatomic features of pilonidal disease are well established and not associated with any particular theory. They include a midline pit in the natal cleft that is referred to as the primary opening. The pit often extends into a subcutaneous fibrous tract called the pilonidal sinus, which connects to a secondary opening.

The secondary opening is located off the midline and is characterized by drainage of purulent or serosanguinous fluid, the presence of granulation tissue, and hypertrophy of the epithelium surrounding the opening. Hair is seen extruding from the primary opening. The pilonidal sinus tract may be single or multiple, short or long, and up to 93% run in the cephalad direction. If the pilonidal sinus runs caudad, the secondary opening may resemble the opening of a fistula-in-ano.

4. Clinical Presentation and Diagnosis

Pilonidal disease can present acutely as a pilonidal abscess or as a chronically draining sinus tract with intermittent symptoms of pain and drainage followed by long quiescent periods. Diagnosis is indicated by the site and appearance of the disease, and identification of midline pits in the natal cleft skin. Findings can be classified into acute pilonidal abscess, chronic pilonidal sinus, and recurrent or complex pilonidal sinus.

• Acute pilonidal abscess can be characterized by a tender fluctuant subcutaneous mass with surrounding cellulitis located off midline of the natal cleft. Onset is rapid and pain is severe.

• Chronic pilonidal sinus has a primary pit in the midline natal cleft located 4–5 cm cephalad to the anus. The pit will sometimes have hair extruding from the opening. There may be a secondary opening located cephalad and off midline at a variable distance from the primary opening.
• Patients with long-standing disease may have complicated pilonidal sinus with multiple sinus tracts and partially drained abscess cavities. Uncommonly, this process can be quite destructive with large sinus cavities extending out into the lateral gluteal regions.
• Occasionally, patients may present with recurrent pilonidal disease having had many different surgical procedures performed in the past for their disease. These patients may have a persistent wound from a midline excision or a failed flap procedure.

The differential diagnosis for these patients includes hidradenitis suppurativa and fistula-in-ano, and, less commonly, actinomycosis and syphilitic or tuberculous granulomas. Patients with chronic draining wounds or multiple failed operations for pilonidal disease may have osteomyelitis with draining sinus tracts. In these patients, a bone scan or magnetic resonance imaging (MRI) should be considered.

5. Treatment

The treatment of pilonidal disease is determined by the initial presentation of the disease.

All acute pilonidal abscesses must be incised and drained.

Most simple chronic pilonidal sinuses can be layed open, while recurrent and complex pilonidal sinuses may require excision with reconstruction.

Optimal treatment protocols for each group include the following goals:

1. ease of performance;
2. short or no hospitalization;
3. low recurrence rate;
4. minimal pain and wound care;
5. fast return to normal activity;
6. and cost effectiveness.

It is important to remember that no single procedure or treatment meets all these criteria.

5.1    Acute Pilonidal Abscess

Drainage of a pilonidal abscess can be performed in the office or emergency room under local anesthesia. The incision is made parallel to the midline and at least 1 cm laterally, to facilitate healing of the wound (see Figure X1).

Figure X1. Incision placement for acute pilonidal abscess.

A small ellipse of skin from the wound is removed is removed to prevent the skin edges from sealing and reforming the abscess. Packing of these wounds is painful and potentially interferes with drainage and healing, and is therefore discouraged.

Simply cover the wound with a dressing and have the patient do Sitz baths or use a hand-held shower to clean the wound and remove hair and debris two to three times a day. Antibiotics are only necessary in the patient with diabetes, prosthetic implants, immunocompromized diseases, or significant cellulitis.

Figure X2. Shaving technique. Two-inch area shaved around gluteal cleft (proximity of pits to anus may limit this)

The patient should return to the office every week or two until the wound heals. Any hair that has grown back within 2 in. of the entire gluteal cleft is shaved during each visit (Figure X2). Once the wound has healed, the recurrence rate is 50% and may be in the form of an abscess or chronic pilonidal sinus.

5.2    Chronic Pilonidal Sinus

Chronic uncomplicated pilonidal sinus has minimal to no acute inflammation. Primary and secondary openings are frequently visualized and the sinus tract connecting the two may be palpable. In these patients, treatment can be either non-operative or operative. The choice of treatment is determined by extent of disease and patient preference.

5.2.1    Nonsurgical Approach

5.2.1.1    Hair Removal

For the initial treatment of chronic pilonidal sinus, shaving alone has been advocated as the sole alternative to surgery. In 1994, Armstrong and Barcia tested the hypothesis that wide, meticulous shaving was equal or superior to surgical therapy of any kind for patients with chronic pilonidal sinus.

The authors performed a pilot nonrandomized cohort study with retrospectively obtained follow-up. One group of patients was treated with weekly strip shaving (5 cm circumferentially around the entire gluteal cleft) until healing occurred and the other group was treated with surgery (any method). They then followed the patients for 3 years, comparing the number of occupied bed days and number of operations required.

The authors found a highly statistically significant difference in favor of the group that received only shaving with lower number of occupied bed-days, with only 23 operations required in 101 consecutive cases of conservative management with weekly shaving. Although this study shows significant benefit for shaving alone, it is important to note that the authors did not gain control for the type of surgery performed in the nonconservative group, or for the severity of disease.

Healing and recurrence rates were not reported, which is a major factor to consider when choosing a treatment modality. Furthermore, the data may be flawed in that it is plausible that although conservatively treated patients were not occupying hospital beds, they still could have been suffering from persistence of their disease, or they may have just sought treatment elsewhere. Despite these limitations, this study provides evidence that conservative nonsurgical treatment through shaving can improve pilonidal sinus healing.

Recently, several authors have described laser hair removal as an alternative to shaving. In a recent retrospective review on laser depilation of the natal cleft to aid in healing pilonidal sinus, the authors report 14 patients treated over 5 years. Only four patients (29%) had on-going disease requiring further depilation using the Alexandrite laser. All patients subsequently healed without complication. The authors concluded that although laser depilation in the natal cleft is not cure for pilonidal disease, it does represent an alternative means of hair removal that is long lasting and allows sinuses to heal rapidly.

Collectively, these data suggest that control of hair in the natal cleft by shaving or laser hair removal may be an effective initial therapy in patients with chronic pilonidal sinus without an acute or chronic abscess; however, it is important to note that it is unknown how long one should continue shaving in order to prevent recurrence. Currently, we recommend shaving until complete healing has occurred.

5.2.2    Surgical Approach

Surgery for pilonidal disease includes incisional procedures and excisional procedures with or without primary closure. As the acquire theory for pilonidal disease has gained wide acceptance, wide excision techniques have fallen out of favor. Minimal surgical techniques for pilonidal disease are now considered as the treatments of choice, and benefit the patient by decreasing hospital stay and minimizing morbidity. For thoroughness, we will describe all surgical options for chronic pilonidal sinus.

5.2.2.1    Midline Excision

Most chronic pilonidal sinus are located midline, therefore, the most common operation performed is midline excision, with or without primary closure. En block excision is made of the entire pilonidal sinus. It is not necessary to always excise down to presacral fascia. The wound can be packed with moist gauze and dressings are changed daily. Excision without closure is associated with prolonged wound healing times, and it seems logical that excision with primary closure would decrease wound healing time and may afford improved outcomes.

Surprisingly, the literature contains only four randomized, prospective studies comparing open excision to excision and primary closure. In 1985, Kronborg et al. randomized 88 patients to one of three treatment groups:

1. excision, leaving the wound open;
2. excision and wound closure;
3. and excision and closure with postoperative clindamycin coverage.

This study is important because it was the first to look at the utility of using antibiotics after pilonidal excision. The authors then looked at recurrence and healing rates. They followed each patient for 3 years. Healing rates between each of the primary closure groups were not statistically significant, and there was no benefit shown from the addition of clindamycin (14 vs. 11days. p>0.10).

Healing took a substantially longer amount of time in the open group compared to the primary closure groups (64 vs. 15 days, p>0.001). Recurrence rates were not significantly in any of the groups (p>0.40); however, there was a tendency toward more recurrences in the primary closure group (7 vs. 0 at 3 months and 7 vs. 4 at 3 years).

Fuzun et al. randomized 91 patients to either excision without closure or excision with primary closure. The authors then followed the patients for a minimum of 4 months. They primarily looked at infection and recurrence rates.

In the two patients who experienced infection in the closed group, this was treated with simple suture removal and healing by secondary intent without the need for further hospitalization. They used no antibiotics. Patients whose wounds were left open had a lower infection rate (1.8% vs. 3.6%, p<0.01) and no instances of recurrence, while the recurrence rate for those undergoing wound closure was 4.4% (p<0.01). They did not specify the duration of healing for either group. Patients who had delayed healing were those few who developed a wound infection. Despite the statistically significant differences in favor of open excision, the authors concluded that either method is acceptable.

Sondenaa et al. randomized 153 patients to midline excision and primary closure with or without cefoxitin prophylaxis; 78 patients received preoperative antibiotics and 75 patients did not receive antibiotics. The complication rate (44% vs. 43%) and wound healing at 1 month (69% vs. 64%) was no different between the groups. Based on this data the authors did not recommend cefoxitin antibiotic prohylaxis.

In a follow-up study published a year later the same group reported their results of a randomized trial of open excision or excision with primary closure for chronic pilonidal sinus. A total of 120 patients were enrolled with half in the excision and primary closure arm and the remainder in the open excision only arm. The patients were followed for a medium of 4.2 years. The authors detected to significant difference between the groups, and therefore, concluded that either method was acceptable.

Collectively, these data suggest that excision with primary closure decreases wound healing time; however, this accelerated wound healing time come with the price of increased wound complications and recurrence of pilonidal disease. Furthermore, the routine use of prophylactic antibiotics is not necessary.

5.2.2.2    Unroofing and Secondary Healing

Midline excision without primary closure leaves a large wound that is associated with prolonged healing times. If wound closure is not indicated (i.e. with an associated abscess), a smaller wound with much shorter healing times can be achieved with unroofing or laying open the pilonidal sinus. In fact, unroofing and curettage has been advocated for the treatment of acute pilonidal abscess and chronic pilonidal sinus.

In a recent study, 297 consecutive patients presenting with chronic pilonidal sinus, acute abscess, or recurrent disease were treated with unroofing and curettage for removal of hair and granulation tissue. The wound was left open to heal by secondary intention.

The investigators found that patients returned to work on average of 3.2 days after the procedure. Mean time for wound healing was 5.4 weeks; however, classification of disease to chronic, recurrent, and abscess revealed a longer wound healing time for abscess group (4.9 vs 5.0 vs 7.2 weeks; p<0.001, respectively). Six patients (2%) developed recurrence, which were believed to be consequences of poor compliance and follow-up.

Postoperative wound care included weekly follow-up with wound debridement and separation of premature skin bridges. Furthermore, the wound area was kept free of hair during wound healing, and the authors stress the importance of hair control to prevent recurrence through the dictum, “No hair, no pilonidal sinus.”

Others have reported similar good results. It is important to keep in mind that open wounds require dressing changes and wound care, but unroofing is associated with half the healing time of wide and deep excision, and marsupialization of the skin edges to the fibrous tract can decrease the wound surface by 50–60%.

5.2.2.3    Bascom’s Chronic Abscess Curettage and Midline Pit Excision (Bascom I)

Bascom bases this procedure on the premise that efforts to treat pilonidal disease should be directed at changing the gluteal cleft conditions rather than excising a large amount of normal tissue associated with the diseased area.

In patients who present initially with a chronic abscess, this procedure has given excellent results. He does this by making a generous, vertically oriented incision through the site of the abscess cavity more than 1 cm off the midline (Figure X3A) and then removing hair and debris through curettage. The fibrous sinus tract or abscess wall is left in place. The connecting tracts to the midline pits are identified and the overlying skin undermined so that they drain to the site of the incision. The midline pits are then excised utilizing a small diamond-shaped incision to circumferentially remove each of them.

Figure X3. A | Bascom procedure. Lateral incision and debridement of cavity. B | Bascom procedure. Removal of a midline pit with small incisions after lateral debridement, and closure of midline wounds without closure of the lateral incision.

According to Bascom, the excised pit should be about the size of a grain of rice. The undermined flap of skin, between the incision and drainage site and the excited midline pits, is then tacked down, and the pit excision sites are closed with either subcuticular or vertical mattress, nonabsorbable suture (4-0 or 3-0) (see Figure X3B). Once this has been accomplished, meticulous shaving of the gluteal cleft should continue at least once a week until the wound has healed. Shaving can be done in the physician’s office, or at home by a family member or friend who has been properly instructed.

Senapati et al. published a perspective series of 218 patients treated with Bascom’s operation described above. The mean follow-up was 12.1 months (range 1–60), and consisted of phone calls, office visits, and mailed questionnaires.

All but one patient healed his or her pit excision sites. The lateral wound in one patient failed to heal and required further excision. All the other wounds healed at an average of 4 weeks (range 1–15 weeks). Eight percent of patients reformed their abscesses when the lateral skin wound healed before the underlying cavity completely healed. This required reopening the lateral wound. Ninety percent of patients healed completely with only 21 patients (10%) ultimately requiring further surgery for recurrent pilonidal disease.

Furthermore, patients who failed to heal or recurred were not any worse than when they initially presented. Therefore, the authors recommend the use of this technique. To date, no trials compare Bascom’s procedure with another approach to chronic pilonidal sinus and abscess.

5.2.2.4    Karydakis Procedure (Advancing Flap)

The Karydakis procedure was first performed by Dr. Karydakis in Athens, Greece in 1965. The procedure involves an elliptical incision that is made parallel to the midline at a distance at least 1 cm from the midline. The skin and gluteal fat that contains the pilonidal sinus are then excised down to the sacral fascia (Figure X4).

Figure X4 | Karydakis advancing flap operation.

Mobilization of the subcutaneous flap is performed on the side closest to the midline to allow advancement to the opposite side. This flap is then sutured down to the sacral fascia, and skin closure should be entirely lateral to the cleft. This procedure achieves two goals:

1. eccentrically excise “vulnerable” tissue in the midline, or laterally displace it, and,
2. laterally displace the surgical wound out of the midline gluteal cleft.

In 1992, Karydakis reported the results of this approach in 7,471 patients over a period of 34 years from 1966 to 1990, and is one of the largest series in the surgical literature.

Follow-up was obtained in 95% of cases, and ranged from 2 to 20 years. He reported a recurrence rate of 1% in the first 6,545 cases, finding that new diseases occurred from new midline pits. The overall complication rate was 8.5%, mainly from infections and seromas or fluid collections. Antibiotics were not routinely used; however, a drain was always placed at the upper end of the wound for 2–3 days.

Recently, the Karydakis procedure was compared to a midline primary closure in a study conducted by the military hospital in Ardahan, Turkey. This retrospective review reported results on 200 military service members treated for pilonidal disease over a 30-month period. The Karydakis procedure was performed on 78 patients and midline primary closure in 122 patients. The authors reported that the Karydakis procedure group had a significantly lower recurrence rate (4.6% vs. 18.4%; p<0.03), lower complication rate (8.9% vs. 30.3%; p <0.02), and higher degree of patient satisfaction (70.8% vs. 32.6%; p<0.001).

These studies indicate that this procedure is highly successful with low complication and recurrence rates; however, comparative series report inpatient hospital stay of over 5 days. This may be due to institution and physician preference as one recent study reported on the successful treatment of chronic pilonidal sinus using the Karydakis flap in a dayf-surgery setting. These data suggest the Karydakis flap is an effective procedure in the treatment of chronic pilonidal sinus, and should be considered in recurrent or complex cases.

5.3.    Recurrent or Complex Pilonidal Sinus

Controversy exists over how to manage patients with recurrent and complex pilonidal sinus. Many of these patients have failed standard surgical treatments and conservative measures such as midline excision and hair control and elimination techniques.

In these complex patients, excision of the pilonidal sinus is combined with a flap closure and modification of the midline natal cleft. These procedures include rhomboid flaps, Z-plasty, the Karydakis procedure (see above), Bascom’s cleft lift procedure, V-Y plasty, gluteus maximus myocutaneous flaps, and skin grafting (see Table X1 Opens in new window).

Some level-one evidence exists regarding flap-based or asymmetric closures off the midline for pilonidal disease, but most data comes from patient series and retrospective reports. The major disadvantages with flaps are longer operative times, greater blood loss, potential flap loss, and infection. However, these flap-based procedures offer a quicker time to healing than midline excision, with no increase in infection rate.

Asymmetric wound closure technique is believed to be one advantage in flap procedures used for reconstruction after excision of complex pilonidal disease. This avoids midline closure and obliterates the natal cleft that are both implicated in wound complications following surgery.

In a retrospective review of the literature, Petersen et al. reported their findings comparing asymmetric closure techniques to midline excision for pilnidal disease. Asymmetric closure was associated with a significantly decreased incidence of recurrence, and the midline pits recurred less often than the midline excision groups.

5.3.1 Rhomboid Flap

The Rhomboid, or Limberg flap, is a cutaneous rotational flap used to fill soft tissue defects. It is ideally suited for pilonidal disease as it brings adjacent healthy tissue to fill the defect after wide excision of sinus tracts and removes the natal cleft from midline (Figure X5A–D).

Figure X5 | Rhomboid flap technique for recurrent pilonidal disease. A Initial excision of the sinus cavity. Counter incisions are created as shown. B Flaps are raised and maneuvered as shown to close defect. C Final surgical result. D Result at 1 month postoperatively.

In 2009, Darwish and Hassanin reported their experience with superior-based Limberg flap. Over a 3-year period, they treated 25 male patients with pilonidal sinus using this flap technique. Operative time averaged 40 (range 30–45) min, and hospital stay averaged 2 (range 1–6) days.

Primary healing was observed in 22 patients, with two patients developing sterile seromas and one patient superficial wound infection. Complete healing of all patients occurred without recurrence during the follow-up period. A larger prospective series used the rhomboid flap on 102 patients regardless of the severity of their disease. Complete healing of the wounds was reportedly 100%; however, time to complete healing was unspecified. They reported a 6% complication rate consisting of three seromas, two partial wound dehiscence, and one wound infection.

The recurrence rate was 4.9%, and these patients were successfully treated with a repeat rhomboid flap. Average time to return to normal activity was 7 days. Collectively, these data suggest that the use of the rhomboid flap for reconstruction after excision of chronic pilonidal sinus is reliable, can be quickly performed in the operating room, and is associated with low complication and recurrence rates.

Given these findings, one may ask, “How does the rhomboid flap compare to surgical excision with primary closure?” Abu Galala et al. randomized 46 patients with chronic pilonidal sinuses either to the rhomboid flap or to midline excision with primary closure. Reported follow-up included postoperative wound healing and recurrence of disease.

Wound healing in the rhomboid flap patients was 100% and was significantly higher than the midline excision with primary closure group (77%;p<0.02). Furthermore, recurrence rate after 18 months follow-up was higher in the midline excision with primary closure group (9% vs. 0%). These data indicate that rhomboid flap closure after complex pilonidal sinus excision may improve wound healing and decrease recurrence rates.

Flap closure results in the creation of large spaces under the flap tissue. Drains have been used to prevent seroma formation and deep wound space infections in an attempt to improve outcomes. However, recent evidence indicates that drains may not improve outcomes. A recent randomized, prospective trial compared the use of drains after rhomboid flap surgery for chronic pilonidal disease. The authors randomized a total of 40 patients, where drains were used in one-half. The study found no difference in wound healing or recurrence (p>0.05), but the drain group did experience a significantly longer hospital stay (p<0.001).

Despite the overall good results with use of the rhomboid flap for recalcitrant pilonidal disease, this technique necessitates excision of a large amount of normal tissue and subsequently creates a large scar at the flap site (Figure X5) . Furthermore, chronic abscesses may be located for lateral and cephalad to the midline pits making the use of this technique more morbid due to the size of the flap required to cover the excised area. However, if the disease is localized close to the midline, the abscess cavity, sinus tracts and midline pits are easily excised. Additionally, this technique should be considered for flap coverage of chronic wounds in the gluteal cleft that have failed to heal over a prolonged period of time.

5.3.2    Bascom Cleft Lift (Bascom II)

This procedure may be the most technically challenging of all the techniques dealing with multiple recurrent and severe pilonidal disease. It also may prove to be the most revolutionary technique to come along since the Karydakis procedure. The key difference between the cleft lift procedure and other flap-based procedures is that normal subcutaneous tissue is not excised in the cleft lift procedure.

As described above, the Karydakis procedure does excise normal fat in order to create a portion of skin. The goal of the cleft lift procedure is to undermine and completely obliterate the gluteal cleft in the diseased area. This procedure detaches the skin of the gluteal cleft from the underlying subcutaneous tissue as a flap. A portion of this flap containing the diseased skin (containing pits) is then excised from the side of the buttocks to which the flap will be sutured (Figure X6A).

Figure X6 | A Cleft lift technique as described by Bascom for nonhealing midline wounds. B Final result after flaps are raised and underlying gluteal fat is approximated.

When the flap is pulled across the midline, the gluteal subcutaneous tissue is approximated underneath the flap, thus obliterating the gluteal cleft. Any open chronic wounds or sinus cavities are simply curetted out, but not excised. The raised skin flaps cover these prior wound sites in addition to coapting the normal gluteal fat. The final suture line lies parallel to, but well away from, the midline, and is free from tension (Figure X6B).

Bascom and Bascom studied 28 consecutive patients with recurrent, festering wounds who received this treatment; 22 patients healed their wounds immediately and had their sutures removed at 1 week. Six patients took longer to heal due to small wound separations. Three patients required operative revision to achieve healing. Finally, one obese patient took 13 months to heal. The median follow-up was 20 months (range 1 month to 15 years) and all patients remained healed. This procedure has enjoyed spectacular results in Dr. Bascom’s hands, but these results awaits duplication.

5.3.3    V-Y Flap

Advancement flaps are designed to slide along the flap’s long axis, and move healthy tissue for reconstruction into the excised area. The size of flap, and therefore, the volume of tissue used, is primarily determined by the arterial input (and venous drainage) not length-to-breadth ratios. The V-Y flap maintains blood supply from the fascia, and division of the blood supply and venous drainage should be avoided.

The use of these advancement flaps have been applied to the surgical treatment of pilonidal disease. Schoeller et al. retrospectively investigated their use of the V-Y advancement flap in 24 patients with complex pilonidal sinus. The mean follow-up was 4.5 years. The investigators reported two cases of wound dehiscence, but achieved healing in all cases. There were no recurrences. Overall, they found the method to be satisfactory, but demanding, and recommended a simpler approach. However, it may have applicability in some situations where other flaps have failed, such as the rhomboid flap.

5.3.4    Z-Plasty

Combining excision with Z-plasty for reconstruction is a well-suited treatment option for complex pilonidal sinus. The diseased tissue is excised and the natal cleft is obliterated with a Z-plasty for reconstruction. The limbs of tissue are fashioned 30–45^o angles from the wound axis. Full thickness subcutaneous skin flaps are raised and transposed before suturing the skin edges. Early application of this technique showed promise with one study reporting no recurrences in 110 patients with pilonidal sinus disease treated with excision and Z-plasty.

Hodgson and Greenstein reported their results of a randomized, prospective study on complex pilonidal sinus treated with Z-plasty vs. midline excision. The Z-plasty group required no further surgery, but 40% of the open excision group did go on to have repeat operations.

In addition to advocating Z-plasty for complex pilonidal sinus excision, this study provides evidence that open excision, while eliminating risk of wound breakdown, does not decrease risk of short-term wound complications.

5.3.4    Myocutaneous Flaps

Myocutaneous flaps are rarely used due to the large nature of the defect and reconstruction created. The procedure may be significantly debilitating as most myocutaneous rotational flaps are harvested from the gluteal area; however, they can be successful for the treatment of pilonidal disease.

Rosen and Davidson reported their series of five patients with severe pilonidal disease treated with gluteus myocutaneous flaps. They were all young males and had received an average of six previous procedures. All patients healed with an average follow-up of 40 months and 13 hospital days. Most surgeons reserve this technique for the most severe cases, usually after failure of multiple simpler techniques.

5.3.5    Skin Grafting

Skin grafting is an infrequent procedure used for the treatment of pilonidal disease. Guyuron et al. published their retrospective study of 58 patients with pilonidal disease treated with excision and split-thickness skin grafting. Over 70% of these patients initially presented with recurrent disease. The authors reported a 1.7% recurrence rate and a 3.4% graft failure rate.

The authors recommended use of this method for recurrent or extensive pilonidal disease; however, there have been no further publications on skin grafting for the treatment of pilonidal disease. This can be explained conceptually, as it does not achieve the modern goals of surgical treatment for pilonidal disease.

Skin grafting leaves the natal cleft left unchanged, requires prolonged hospital stay for wound care of donor site and graft site, and the graft site, generally the sacrum and/or gluteal area is in zones of high friction. Furthermore, graft success is likely to require significant immobility that prolongs return to normal activity. Taking these factors into account, we cannot recommend skin grafting for the treatment of pilonidal disease.

6.    Summary

Treatment of pilonidal disease is dependent on the disease presentation. Pilonidal abscess, chronic sinus, complex sinus tracts, and chronic recurrent pilonidal abscess and sinus encompass the spectrum of pilonidal disease. Each has specific considerations in the treatment and management of this disease process; however, the cornerstone of all surgical and nonsurgical therapeutic interventions for pilonidal disease should always include wide, meticulous shaving and hygiene.

The algorithm in Figure X7 outlines a common approach to pilonidal disease based on the evidence presented in this entry. In patients presenting initially with simple midline pits, or sinus tracts without acute abscess, shaving can be offered as the initial treatment.

Figure X7 | Pilonidal disease algorithm

Meticulous and ritualistic shaving is critical as one single hair protruding from a midline pit will keep it open and result in recurrent or persistent disease. During both the primary and postoperative healing phase, shaving should be continued on a weekly basis until healing is complete. Patients with acute pilonidal abscess require incision and drainage, ideally making the incision lateral to the midline whenever possible. At the same time, one should do a 2-in. strip shave circumferentially around the affected area.

Dressing changes, Sitz baths, and shaving are continued until the wound has healed. The majority of acute pilonidal abscess treated in this manner do not recur.

Many patients will present initially with chronic pilonidal sinus. Location of the sinus relative to the midline helps guide the choice of management. In the case where all the disease, sinuses, and pits are located near and in the midline, then a conservative midline excision or unroofing with curettage is a reasonable first line treatment; however, if multiple draining sinuses exist, and they are located far from the midline, then simple midline excision becomes impractical due to the larger wound created.

In this case, we recommend the Bascom I procedure or excision with rhomboid flap reconstruction. These procedures are also useful for patients who have failed midline excisions. Patients presenting with multiple recurrent pilonidal disease, or chronic persistent abscess despite conservative management, are more challenging to treat.

Continued shaving in this situation is unlikely to succeed, since the abscess cavity and the epitheliazed tracts connecting it to the midline pits will contain a great deal of burrowed hair. In this case, we recommend the Basecom I procedure with chronic abscess curettage and midline pit excision. Alternatively, a cutaneous flap procedure with asymmetric closure is also effective.

In the event, a prior operation results in a chronic non-healing wound, a rotational flap is ideal. These flaps should move the wound closure and natal cleft off the midline. In these circumstances, we suggest the rhomboid flap for this purpose. For extensive recurrence in the midline with abscesses and multiple nonhealing wounds, the Bascom II cleft lift procedure or Z-plasty may be effective. Myocutaneous flaps are reserved for patients with severe complex surface areas. In these situations, consultation with a plastic surgeon may be advised.