Pilonidal sinus

• It is of infective origin and occurs  in sacral region between the buttocks, umbilicus, axilla.
• It is also common in hair dressers (seen in interdigital clefts), jeep drivers.
• Common in third decade of life. It is common in males and mostly hairy males.
• Most common site: Interbuttock sacral region

Pathology

• The sinus extends into the subcutaneous planes as an infected track. There may be branching side channels.
• Stratified Squamous epithelial lining of varying degree of integrity can be found in many cases.
• Hair shafts are found lying loose in the sinus, embedded in granulation tissue or deep in mature scar tissue.
• Foreign body giant cell maybe present.

Clinical features

• Discharge- either sero sanguinous or purulent.
• Pain- throbbing and persistent type.
• A tender swelling seen just above the coccyx in the midline (primary sinus); and on either sides of the midline (secondary sinus)
• Tuft of hairs may be seen in the opening of the sinus.
• Presentation may be as an acute exacerbation, or as a chronic one.

Treatment

• Initially drainage of an abscess (acute phase), and later t/t for the sinus.
• Definitive t/t is excision of all sinus tracks with removal of hairs and unhealthy granulation tissues under G/A (In Jack knife posotion)
• Methylene blue is injected to demonstrate the branches of the sinus.
• Secondary closure or delayed skin grafting is done or left to heal by granulation.
• Recurrence rate is very high.
• Bascom technique: Through lateral approach, sinus is reached and excised.