Avulsion injuries of the pelvis

Pelvic avulsion injuries occur in both the skeletally immature and adult patient populations. Avulsion injuries are most common in the adolescent age group and usually present as an avulsion of the unfused apophysis at the level of tendon attachment resulting from violent muscular contraction during an athletic endeavor. Acute apophyseal avulsion injuries are usually easily detected and adequately imaged with radiographs, but occasionally advanced imaging such as magnetic resonance imaging or computed tomography is required to detect and fully delineate the extent of injury. Chronic injuries can mimic a more aggressive lesion, but familiarity with the location of various tendon attachment sites on the osseous pelvis can help avoid this pitfall. Traumatic avulsion injuries can also occur in the skeletally mature pelvis; however, in the adult, the presence of a pelvic avulsion fracture in the absence of trauma should be considered a pathological lesion until proven otherwise. This article discusses the clinical and imaging findings of apophyseal avulsion injuries in the adolescent athlete, followed by a discussion of specific pelvis avulsion injuries that occur in the adult population.