Abstract
Five patients with tylosis-like plaques on the sacro-coccygeal area were reported. All cases were young male, aged 6 to 15 years. The lesions were asymptomatic, light brown to light red in colors, elastic soft to firm in consistency and the surface was fine granular. Macroscopically they were similar to tylosis or knuckle pad. Histological examination revealed extremely increased dermal collagen fivers with hyperkeratosis and acanthosis in epidermis.
On the bone X-ray examination, the coccygeal bones were displaced anteriorly on lateral view forming right angle between the coccygeal bones in all the cases. This coccygeal bone's deformity seems to be the cause of the skin lesions.
