Pilonidal Disease



  • Pilonidal disease results from an abscess, or sinus tract, in the upper part of the natal (gluteal) cleft.
  • Synonym(s): jeep disease



  • 16 to 26/100,000 per year
  • Predominant sex: male > female (3 to 4:1)
  • Predominant age: 2nd to 3rd decade, rare in age >45 years
  • Ethnic consideration: whites > blacks > Asians

Surgical procedures show male:female ratio of 4:1, yet incidence data are 10:1.

Etiology and Pathophysiology

Pilonidal means “nest of hair”; hair in the natal cleft allows hair to be drawn into the deeper tissues via negative pressure caused by movement of the buttocks (50%); follicular occlusion from stretching and blocking of pores with debris (50%) creating a pilonidal cyst

  • Inflammation of SC gluteal tissues with secondary infection and sinus tract formation
  • Polymicrobial, likely from enteric pathogens given proximity to anorectal contamination


  • Congenital dimple in the natal cleft/spina bifida occulta
  • Follicular-occluding tetrad: acne conglobata, dissecting cellulitis, hidradenitis suppurativa, pilonidal

Risk Factors

  • Sedentary/prolonged sitting
  • Excessive body hair
  • Obesity/increased sacrococcygeal fold thickness
  • Congenital natal dimple
  • Trauma to coccyx

General Prevention

  • Weight loss
  • Trim hair in/around gluteal cleft weekly.
  • Hygiene
  • Ingrown hair prevention/follicle unblocking

There's more to see -- the rest of this topic is available only to subscribers.