A pilonidal cyst is a fluid-filled sac that typically occurs near the tailbone, at the top of the buttocks crease. This condition is more common in young men and can cause significant discomfort. A pilonidal cyst can become infected, leading to the formation of an abscess, which may require medical intervention. The exact cause of pilonidal cysts is not well understood, but they are believed to be associated with hair and skin debris trapped under the skin.

The term ‘pilonidal’ comes from Latin words meaning ‘nest of hair’. The first recorded mention of this condition dates back to 1833 when it was described by Herbert Mayo. It gained significant attention during World War II when it affected many soldiers, leading it to also be called ‘Jeep disease’. The condition was associated with prolonged sitting, which was common among soldiers driving jeeps. Early treatments were often surgical, involving the extensive removal of tissues.


The exact cause of pilonidal cysts is not entirely understood, but several factors are thought to contribute:

Hair and debris: Hair and skin debris can become trapped in the skin, leading to the formation of a cyst.

Hormonal changes: Changes during puberty can increase the risk.

Friction and pressure: Prolonged sitting, tight clothing, or repetitive motion can irritate the skin and contribute to cyst development.

Genetic predisposition: A family history of pilonidal cysts may increase the likelihood of developing the condition.

Risk Factors

Several factors can increase the risk of developing a pilonidal cyst:

  • Age: Young adults, especially those in their late teens and early twenties, are more commonly affected.
  • Gender: Males are more likely to develop pilonidal cysts.
  • Obesity: Excess weight can increase pressure and friction in the area.
  • Sedentary lifestyle: Prolonged sitting can contribute to the development of these cysts.
  • Excess body hair: Having a lot of hair in the buttocks region can increase the risk.


If left untreated, pilonidal cysts can lead to several complications:

Infection: The cyst can become infected, forming an abscess that may require drainage.

Chronic or recurrent cysts: Cysts can recur, leading to chronic discomfort and repeated infections.

Cellulitis: An infection that spreads to the surrounding skin can cause cellulitis, a serious skin condition.

Fistula formation: In severe cases, an abnormal connection (fistula) may form between the cyst and the skin surface.


While not all pilonidal cysts can be prevented, certain measures can reduce the risk:

  • Good hygiene: Keep the area clean and dry.
  • Hair removal: Regular hair removal (shaving or laser hair removal) in the area can reduce the risk of hair becoming trapped under the skin.
  • Avoid prolonged sitting: Take breaks to stand and move around if you have a sedentary job or lifestyle.
  • Maintain a healthy weight: Reducing excess weight can decrease the risk of cyst formation.


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