Pilonidal Cyst

A pilonidal cyst is believed to be an acquired condition caused by the presence of hair in involuted epithelial tissue in the natal cleft. Pilonidal sinus disease is a chronic, recurrent disorder of the sacrococcygeal region, which commonly occurs in young adults following puberty. The male population is affected more frequently compared with the female population.

Some clinicians have theorised that this condition is a congenital one, but it is now more generally accepted that the presence of hair in the natal cleft causes a foreign body–like reaction that leads to inflammation and possibly infection.

Risk factors that have been attributed to developing a pilonidal cyst include the following:

• Increased friction or abrasion in the area
• Increased hair
• Deep natal cleft

A large number of surgical techniques (with varying complexity) have been described in the literature for the treatment of this disease. Such diversity suggests that no single technique has emerged as the preferred method in preventing recurrence of this condition.

Pilonidal cystectomy is the surgical removal of a pilonidal cyst or tracts extending from a sinus. It may range from a simple procedure that involves excision of a small amount of tissue to a very complex procedure that may include allowing the wound to heal secondarily or rotating adjacent tissues into the defect after excision.

An asymptomatic pilonidal disease does not necessitate any treatment. A pilonidal abscess should initially be locally incised followed by one of the definitive treatment methods after regression of the acute inflammation.

A primary complete excision of the abscess and open wound treatment is as¬sociated with a prolonged healing time. An excision of the pilonidal abscess and primary wound closure is associated with increased morbidity and recurrence rate and should be avoided. The basic treatment method of chronic pilonidal disease is surgical excision. Open wound treatment after pilonidal excision is associated with a low postoperative morbidity; however, this method is complicated by a considerably prolonged wound healing.

Minimally invasive procedures (e.g. pit picking surgery) represent a treatment option for chronic pilonidal disease; however, the recurrence rate is higher compared to open procedures. Excision followed by a pri¬mary midline wound closure bears no advantages to other methods and should be avoided. An off-midline surgical approach can be adopted as a primary treatment option in chronic pilonidal disease. At present, there is no evidence of any outcome differences between various off-midline procedures. The Limberg flap and the Karydakis procedure are the two best described methods.

Medical management may reduce the severity of disease. Proper hygiene is paramount. Local hair control by laser epilation has been shown to be an effective therapy that decreases recurrence. Lifestyle changes to reduce repetitive trauma or friction to the area have also been encouraged. Pilonidal cysts that are not amenable to medical management should lead to surgical referral for further evaluation.

Indications

Pilonidal cystectomy is indicated for any patient who are symptomatic, that is has pain or discomfort from the presence of the pilonidal cyst. Occasionally, a pilonidal sinus is encountered on
physical examination that is not causing any deficits. Surgery may be deferred in these instances.

Contraindications

The pilonidal cyst may become infected. Closure after pilonidal cystectomy is contraindicated in any patient with an active infection. In these cases, antibiotics should be prescribed and the procedure deferred until the infection has been cleared. In certain cases, drainage of an abscess is performed and a radical cystectomy is deferred until the infection has cleared.

Periprocedural Care

Patient education and consent

All patients should be counseled about proper hygiene to the area. Patients with a significant amount of hair in the area may benefit from hair removal strategies. For proper healing, patients may need thorough instructions for care and dressing changes. A dressing can be as simple as a dry rolled gauze held in place with tightfitting underwear or a small amount of tape. A wound care nurse may be consulted for care of complex wounds that require packing the wound or for sponge dressing
changes on negative-pressure wound therapy devices.

Patients should minimize any shear stress to the area by not performing any running, twisting, or repetitive motions (eg, biking or horseback riding), friction (eg, motorcycle riding or off-roading), or exercises on the back (eg, situps). Patients should lie on the abdomen or on one side when sleeping.

Equipment
A standard minor surgery set is used for this procedure. Electrocautery with a smoke evacuator is preferred. An anoscopy set should be available to examine the anus and rectum in cases where the cyst or sinus tracts are close to the anorectal canal. A lacrimal duct probe and a curette set should also be available.

Patient preparation

Pilonidal Cystectomy: Overview, Periprocedural Care, Technique

Anaesthesia

For very small pilonidal cysts or for drainage of an abscess, the procedure can be performed with local anesthesia using 1% lidocaine mixed with 0.25% bupivacaine and epinephrine. For a simple pilonidal cystectomy, the patient may be offered spinal anesthesia and local anesthesia with monitored anesthesia care. For larger or more complex procedures, local and general anesthesia may be preferred.

Positioning
For most procedures, patients are placed in the prone jackknife position with slight Trendelenburg. If necessary, the patient’s buttocks are held spread apart by attaching long pieces of tape from the buttocks to the operating table.

Monitoring and follow-up

Follow-up depends on the type of procedure performed. If primary closure is attempted, patients generally follow up in 2 weeks, then as needed. If the wound is left open to heal secondarily, then follow-up may have to be more frequent until patients are able to care for the wound themselves. In these cases, daily wound care is often required, including packing the wound with gauze and covering with tape.

Many surgeons recommend using a razor or clippers to remove hair around the natal cleft on a weekly basis as needed after surgery. One study surveyed patients who had a pilonidal cystectomy and had been instructed to use a razor to remove hair. Over a mean follow-up of 11 years, those who performed razor epilation had a higher recurrence rate, 30.4%, compared with those that did not perform
postoperative epilation, at 19.7%. On the basis of this study, the authors recommended against using a razor for epilation postoperatively.

Many small studies have been performed evaluating laser epilation postoperatively. In the 1- to 3-year follow-up periods, there is a significant reduction in recurrence. However, many of these studies use different types of lasers with different treatment schedules. Collectively, these studies suggest that laser epilation prevents recurrent pilonidal disease. Long-term studies may be warranted to further elucidate the role of laser epilation.

Technique

Approach considerations

The goal of surgery for a pilonidal cyst is to remove all cystic tissue and allow
healing of healthy tissue. Surgical approaches to pilonidal cystectomy may be
divided into the following two broad categories:

• Open healing
• Wound closure
• The various specific techniques include the following:
• Simple cystectomy
• Cystectomy with primary closure
• Karydakis flap
• Bascom procedure
• Limberg flap
• Z-plasty
• Y-V plasty
• Myofascial flap closure

Other techniques have been used and are variations of these techniques, including an elliptical flap and an oblique excision. Simple cystectomy and primary closure is reserved for small cysts.

The primary treatment for any infected pilonidal cyst with an underlying abscess is antibiotics with incision and drainage. Antibiotics should cover skin flora; some recommend anaerobic coverage with metronidazole. Surgical referral should be made after the infection has cleared for definitive pilonidal cystectomy. Practice parameters for the management of pilonidal disease have been developed by the American Society of Colon and Rectal Surgeons .

Preparation

The patient is prepared by clipping any hair around the affected area. (See the image below.) The natal cleft is exposed by applying tape to the gluteals, gently stretching the tissue to the lateral sides, and securing the tape to the table. Iodine-based solution is generally used for prepping unless the patient has an allergy.

Anatomical landmarks (back view).

Begin by identifying all sinus tracts (see the image below) and gently probing them with a lacrimal duct probe. Care must be taken not to create false tracts in the surrounding tissue. Injection of methylene blue has been used to identify tracts as well. A local anaesthetic is injected around the area.

Pilonidal cyst.

Simple cystectomy

For simple cystectomy, electrocautery is used to dissect the tissues toward the sacrum around the cyst and sinus tracts. Dissection is performed in healthy tissue approximately 0.2 cm lateral to the identified sinus tracts. For small cysts, dissection can continue ventral to the cyst from both sides. In larger cysts, dissection is continued until the fascia overlying the sacrum is encountered, but the fascia is left intact. Occasionally, the walls of the wound are debrided further with curettage and laser ablation may be applied. Hemostasis is maintained with electrocautery.

Open technique

Traditionally, wounds are left open, covered with gauze, and allowed to heal secondarily. Compared to other methods, this technique has a shorter time in the operating room.[11] However, this technique has long healing times, requires daily dressing changes, and has a 10% recurrence rate.

After removal of large cysts or actively infected tissue, a negative pressure wound therapy device can be placed over the wound. These dressings are changed every third day. The negative pressure wound devices reduce the bacterial load, shorten healing times, and provide local debridement with each dressing change. Another option for large wound defects is to marsupialise the wound edges by sewing the wound edges to the postsacral fascia. This decreases the amount of exposed tissue.

Primary closure

After a small simple cystectomy with no tension on the skin edges, the wound may be closed primarily with nylon using interrupted vertical mattress sutures. Deeper wounds may be closed in layers. Absorbable sutures can be used to close the deeper space by incorporating the postsacral fascia.

Techniques for complicated or recurrent disease

Other methods are chosen based on the amount of tissue removed, surgeon preference, and contour and tension of the wound.

Karydakis flap

A Karydakis flap is design to move the wound away from the midline. In brief, an elliptical incision is made lateral to the midline. Instead of dissection straight down to the fascia, the tissue is dissected at an angle toward the diseased tissue. The deep tissue is sutured to the sacral fascia. The skin is closed primarily lateral to the midline.

Bascom procedure

A Bascom procedure (cleft lift procedure) is a modification of the Karydakis flap and has been shown to reduce recurrence rates of pilonidal disease. An ellipse of diseased tissue is removed, but the deep tissues are not removed. A wide excision is not preferred. A 7-mm skin flap is created on one side and brought across the midline to approximate the tissues away from the midline. The wound is closed with nylon sutures. This technique also reduces the depth of the natal cleft. Bascom reported no recurrences.

Limberg flap

A Limberg (rhomboid) flap is designed to keep the healing wound away from the midline. A rhomboid-shaped incision is made over the diseased tissue in the midline. A modified version keeps the apices of the incision away from the midline. A rhomboid-shaped flap is dissected from one side, including the gluteal fascia, and rotated into the wound defect. The lateral defect is closed primarily.

Z-plasty

A Z-plasty is designed to decrease tension on the wound after repair. An elliptical incision is made to remove the cyst, including the deep tissue. The limbs of the Z incision are made at angles of approximately 30º to the midline. Two triangular flaps of tissue are raised and transposed. The wound may be closed in layers.

Y-V plasty

A Y-V plasty is designed for large wound defects with significant skin tension. All diseased tissue is removed from the midline with an elliptical incision. A V-shaped incision is then made lateral to the tissue beginning from the apices of the ellipse. The subcutaneous tissue is dissected to allow the healthy tissue to be advanced over the wound defect. This technique also flattens the natal cleft.

Myofasciocutaneous gluteal flap

A myofasciocutaneous gluteal flap is reserved for very large wounds for which previous methods of pilonidal cystectomy have failed. It is usually performed by very experienced surgeons or plastic surgeons. There are several variants of the procedure, which involve isolating part of the gluteal muscles and the superior gluteal artery blood supply. The flap is rotated into the wound defect. This procedure has a long operating time and is associated with a higher complication rate than other techniques.

Complications

Complications of pilonidal cystectomy include the following:

• Wound dehiscence
• Infection
• Delayed healing
• Recurrent disease requiring reoperation
• Pain

The most common complication involves delayed wound healing. In cases where the wound has been closed, the wound may not heal and sutures may have to be removed to allow drainage of excess fluid. Delayed wound healing may also be caused by excessive tension on the wound.

The wound may become infected after surgery. Gram-positive cocci are the most common etiologic agents. Antibiotics for skin flora and anaerobic bacteria may be prescribed empirically and cultures obtained for sensitivity testing. If an abscess develops, the fluid should be drained by removing the sutures.

For extensive wounds that were left open, the patient may feel a significant amount of pain from changing the dressings once or twice daily.