Types of Pilonidal Cysts

Manifestations of the Coccygeal fistula

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Munich Classification of Coccygeal fistula

A coccyx fistula (sinus pilonidalis) can occur in various forms. The appropriate treatment depends on the respective species. For every operation you first need a good plan. This requires careful investigation. To do this, we take a close look at the problem: under magnification with magnifying glasses, it is best to see all the details of a pilonidal sinus. We use ultrasound to look under the surface and thus avoid unpleasant surprises during the operation. We have an individual concept for every situation. The following classification explains how we free you from your coccyx fistula in various starting situations.

Coccygeal fistula Type I A

There are less than four pits and the fistula duct is less than two centimetres short. Such a coccyx fistula can be removed through a single small opening. The operation is precise and gentle with the RF scalpel. Although this simplest form of coccyx fistula is easy to treat, follow-up examinations should not be neglected.

Coccygeal fistula Type I B

In this form there are less than four pits - the fistula duct is longer than two centimetres. In this case, it can usually be completely removed via two small accesses at the starting point and end point of the fistula. Also in this case the impairment of the patient is small and a healing is to be expected in over 90 percent of the cases.

Coccygeal fistula Type II A

Type IIa shows more than four pits and the fistula tract exceeds a length of two centimetres. In this case, too, we aim to peel out the fistula duct as a complete tube. Sometimes, however, it can be more gentle to remove only hair roots, loose hair and fistula tissue and treat the duct with the laser.

Coccygeal fistula Type II B

There are more than four pits and the fistula duct is also longer than two centimetres in this form. A blindly ending, sack-shaped dilatation of the fistula duct is often the cause of pain radiating to the back, so that patients often consult an orthopaedist because of back pain. The coccyx fistula type II b can be treated with pit picking and laser is less invasive. A fistulectomy offers slightly higher healing rates, but usually requires an additional incision at the end of the fistula.

Coccygeal fistula Type III

In these patients, the fistula developed secondary as a result of congenital, funnel-shaped retraction of the skin in the gluteal fold. Such a skin change can be found in many people, most of whom have no impairments. Hair that is bundled by constant rubbing in the gluteal fold can eventually lead to an opening at the lowest point of the funnel and to hair ingrowth. This leads to the formation of a fistula cave. With this form we cut the funnel very sparingly and release the fistula capsule. Shaving the surrounding skin or treating it with laser epilation is particularly important here.

Coccygeal fistula Type IV A

This type of fistula can be seen after conventional pre-operation. Both hair that grows in from below and loose hair that has reached the wound during wound healing are the cause of a new fistula tube. It is not uncommon for a visible opening of the fistula to extend far into the seemingly healthy scar area. In addition to intensive laser epilation, the method of choice is to clean the cavity through the existing opening (debridement). Endoscopy facilitates the operation by means of which otherwise difficult to see areas of the fistula cavity can be checked on the monitor.

Coccygeal fistula Type IV B

This form can occur when the wound fails to heal and a new fistula forms (pseudo recurrence). If a coccygeal fistula has already been cut out generously, the wound will not close even after years. Causes for this are ingrowing hairs from the wound edge or loose hairs from the back or head. A new fistula capsule forms. In most cases, healing is achieved by removing the ingrown hairs, peeling out the fistula capsule and intensive laser epilation of the surrounding area. Another radical fistula operation should be avoided at all costs. Any further extensive excision reduces the cushioning of the region and worsens the chances of healing. Plastic reconstruction according to Karydakis is an alternative that we only use if the minimally invasive procedure is not successful.

Course of the Coccygeal fistula

"Blande" Shape

This refers to the incidental finding of a coccygeal fistula during an examination for another reason and in a patient who has no complaints whatsoever from this fistula. This is comparatively rare. Most patients have complaints, but they did not know the cause until the diagnosis was made.

Chronic Form

The chronic form refers to the presence of a fistula tract without significant signs of inflammation, i.e. pain, redness, hyperthermia or swelling of the surrounding tissue.

Acute Form

The acute form refers to the anal abscess or coccygeal abscess, which usually develops quickly within a few days and leads to massive pain.