Morel-Lavallee syndrome is a posttraumatic soft tissue injury in which the subcutaneous tissue is broken off from the underlying fascia, creating a cavity filled with hematoma and liquefied fat. It commonly occurs over the greater trochanter and, rarely, may also occur in the lumbal region.Morel-Lavallee syndrome can be often diagnosed late because of ommitted diagnosis in emergency services. The emergency physician and radiologist must keep this syndrome in mind because early diagnosis can enable conservative management, whereas delayed diagnosis may lead to surgical exploration. In this article,we present the clinical and radiologic features of 2 cases of lumbar Morel-Lavallee syndrome detected after trauma.