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A new classification according to navicular area concept for sacrococcygeal pilonidal disease

Dear Sir, Many procedures have been described for the treatment of sacrococcygeal pilonidal disease (SPD), also known as pilonidal sinus. None is perfect in terms of primary healing and recurrence. Conservative approaches such as weekly shaving of the involved area may control progress of the disease but surgical treatment is often required as supervening infection is inevitable in most cases [1,2]. Although a simple excision and lay-open technique was widely used, many surgeons abandoned this approach due to the incidence of discomfort, long hospitalization and very high recurrence rates [2,3]. Excision and primary closure in the midline is also associated with wound breakdown, delayed wound healing or late recurrence [3]. For this reason oblique incision and excision techniques have been introduced during the last three decades to avoid the problems believed to be associated with a midline scar [1,2,4]. The main problem as Bascom pointed out is, however, the ‘deep natal cleft’ where the epidermis is exposed to moisture, anaerobic conditions, hair, débris and bacteria [5]. These ‘environmental’ factors cause a problem at the epidermal level where pilonidal disease originates. The treatment should therefore be focused on changing these conditions using a superficial rather than the often-practised ‘deep’ and wide excision, which removes deep and healable tissue. On the basis of this more modern understanding of SPD, a new classification of the disease is proposed based on the concept of the ‘navicular area’.