Brief Answer:
Pilonidal sinus

Detailed Answer:
Thank you for contacting HCM with your health care concerns

You are wondering what a pilonidal sinus is. First a pilonidal cyst is a small cyst or pocket at the base of the coccyx between your butt cheeks. This is a congenital abnormality and is very common. The pilonidal sinus is a canal from the outside skin into the cyst. This allows bacteria to enter and cause infections in the cyst. Again very common problem. When the pilonidal cyst gets infection we usually use antibiotics to clear the infection. Unfortunately these cysts become chronically infected and require surgery. This surgery is painful and not often successful because of the limited tissue growth and the amount of bacteria in that general area.

I hope I answered your question. Please contact us again if you have any additional questions

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