[Aspects of expert opinions of avulsion fractures].

The apophyses as secondary ossification centers are connected with the bone by cartilage. During the growth phase of puberty, the apophyseal plate is a mechanical weak spot. Especially, apophyses in the hip and pelvic area are exposed to considerable tensile and sheer stresses due to the strong muscles which are inserted here. The frequency of injuries to the apophyses correlates with the extent of sporting activities. For athletes participating in "Youth Train for the Olympics", this is the most common injury of all. Most often, the apophysis of the rectus femoris muscle is affected at the anterior inferior iliac spine. In adults, after complete ossification of the apophyseal plate such injuries are rare. However, in a very unusual mechanism of injury with maximum forced hip flexion and simultaneous maximum knee extension, avulsions of the ischial tuberosity are observed in adults. During the causality test-especially in the legal area of statutory accident insurance-the question is always whether the alleged course of events has to be regarded as a legally significant (partial) cause or if a longer period of time has been involved, so that the resulting morbid apophysis detachment was predominately due to fate, in which the alleged event must be interpreted as legally immaterial.