The epiphyseal tubercle in adolescent hips.

BACKGROUND

It has already been shown in animals and using anatomical human specimens that chronic slippage of the adolescent upper (capital) femoral epiphysis is unlikely to take place by shearing due to the presence of an epiphyseal tubercle projecting down into the metaphysis.

MATERIAL, RESULTS, AND INTERPRETATION: Plain radiographs of 20 adolescents and CT scans of 9 of them were analyzed for evidence of the size and presence of this tubercle in vivo. These cases showed that CT scanography is the investigation of choice to illustrate this largely undescribed anatomical feature. They also illustrate the epiphyseal tubercle well, both in the anatomical position and at various stages of "epiphyseal slippage", and confirm that it has a significant restraining effect on any tendency of the epiphysis to alter its position relative to the metaphysis.