- 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
- 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.
- 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.
- 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.