Ischial tuberosity apophysitis and avulsion among athletes.

Ischial tuberosity pain in athletes may be caused by several clinical entities, which include acute and old bony or periosteal avulsions and apophysitis. We studied the natural course of these injuries based on our clinical case series of fourteen patients with apophysitis and twenty-one with avulsion of the ischial tuberosity. Only patients with the diagnosis confirmed by X-ray finding were included. The clinical diagnostic criteria by ischial apophysitis consisted of gradually increasing functional and palpatory pain at the ischial tuberosity without any major trauma at the beginning of the symptoms. Typically there was asymmetry on plain radiographs of the ischial tuberosities in apophysitis; the involved apophyseal area became sclerotic, wider than the non-symptomatic apophysis, osteoporotic patches developed and the lower margin of the ischial tuberosity became irregular. The patients with avulsion reported an acute trauma at the beginning of the symptoms and an avulsion fragment was immediately after injury or later seen in plain radiographs. The mean age of the patients with apophysitis (14.1 yrs) was lower than that of the subjects with avulsions (18.9 yrs). Apophysitis of the ischial tuberosity usually healed well without complications. Avulsions often caused more prolonged pain with referral pain to the posterior parts of the thigh which often required operative interventions. A small bony or periosteal avulsion sometimes grew to a pseudotumor calcification. We recommend conservative treatment as the primary treatment modality for both ischial tuberosity apophysitis and avulsion fractures.