Fig. 7.

Sagittal view of pilonidal disease. The pit is the result of a deformed hair follicle. Often with subcutaneous accumulation of hairs. The sinus is an epithelial tube after destruction of the follicle, with connection to the cavity, which contains granulation tissue and often hairs. The cavity drains through the tract. The dashed lines indicate the minimal excisions needed.

(Modified from an original drawing by Gips et al. [11])