Sacral tail sinus formation

Pilonidal sinus and Pilonidal cyst are collectively referred to as Pilonidal disese, which is a chronic sinus tract or cyst in the soft tissue of the cleft gluteal cleft, with hidden hair as its characteristic. It can also be manifested as an acute abscess of the zygomatic tail, forming a chronic sinus after perforation, or temporary healing, eventually perforation, which can be repeated. The cyst is accompanied by granulation tissue, fibrous hyperplasia, and often contains a tuft of hair. Although the disease can be seen after birth, it usually occurs in 20 to 30 years of age after puberty. Symptoms only occur due to increased hair fat gland activity.