A coccyx fistula is a chronic inflammatory disease in the area of the gluteal fold (lat. Rima ani). As a rule, patients between the ages of 20 and 30 years of age in particular present themselves to their family doctor because of the presence of a coccyx fistula.
It is estimated that approximately 26 out of every 100,000 people in Germany suffer from coccyx fistula every year. A similar clinical picture can occur between the individual fingers or toes. However, the reason for this phenomenon has not yet been conclusively clarified.
Many theories are circulating about the development of coccyx fistulas. Three of these theories have become established in medicine and everyday clinical practice and are considered to be the most likely. Today, it is assumed that the development of a coccyx fistula is directly related to the daily strain on the skin and soft tissues in the coccyx area.
Frequent sitting, heavy hair growth and the resulting ingrowth of hair are assumed to be the cause. Here, the penetration of the hair tips into the epidermis plays a particularly important role. In addition, an error during hair formation (so-called hair formation disorder) can already lead to the development of a coccyx fistula.
In these cases, it can be proven that the keratin formed by the root region could not be built up into a hair in an orderly fashion. Rather, a clod-shaped deposition of the keratin occurs and from this, the formation of a so-called foreign body granuloma. Infection with bacteria of the normal skin flora leads to purulent inflammations in the affected areas.
This theory is based on the finding of tufts of hair in the fistula tract or abscess cavity of affected patients. Another assumption describes the connection between congenital malformations that have already developed in the course of embryonic neural tube closure. Furthermore, it is assumed that enormous force effects during trauma can promote or even provoke the formation of coccyx fistulas.
