The apophysis of the ischial tuberosity usually becomes united with the hipbone by 25 years of age. The highest incidence of avulsion in this region occurs between 15 and 17 years in young active persons. Apophysitis should be differentiated from apophyseolysis or an avulsion fracture of the ischial tuberosity. Apophysitis may be associated with chronic excessive sports activities in young men and women and is manifested by pain in the region involved. Its presence is confirmed by radiographic findings. The patient with an avulsion fracture of the ischial tuberosity reports an injurious event, usually a sudden movement during sports activities, associated with immediate pain. The diagnosis is again confirmed by radiology. Apophysitis is treated conservatively with no resulting problems. The poor healing of an avulsion fracture may result in chronic complaints, particularly painful sitting. This condition is treated by resection of the fractured apophysis. The authors describe the case of a 28-year-old man who complained of experiencing pain when sitting. At 20 years of age, he suffered an avulsion fracture of the ischial tuberosity that was treated conservatively. He was examined at our department and an unhealed fracture of the ischial tuberosity was diagnosed by radiology and computed tomography. The separated bony fragment was removed and the patient was followed up to 1 year. He remained free from any complaints. An avulsion fracture of the ischial tuberosity is an injury rarely reported in our as well as foreign literature. The available case reports are discussed.

Urazová nemocnice Brno