There are several reports on the intervertebral vacuum phenomenon since Maldague s report in 1978. This disease is, however, considered as uncommon and miscellaneous entity. We performed retrospective review of 27 collapsed vertebral bodies of 21 osteoporotic patients to define the clinical, radiological and pathological characteristics of intravertebral vacuum phenomenon. Simple radiographs and MRIs were reviewed and the pathological findings from 6 specimens were matched with MRI. Intravertebral air shadows were shown in all cases either on A-P or lateral view, more definite on extension lateral views. Basically, it was considered as a burst fracture with loss of anterior and middle column height. The extent of collapse could be classified as complete or incomplete and the shape of spinal canal intrusion as bulging or local beak type. 12 cases of MRI findings were classified in to three types by T1, T2 and gadolinium enhancement patterns. The extent of spinal canal intrusion was less then 50% in all cases but neurolgic deficits were examined in 10 cases. Pathologically, necrotic trabeculae with fibrous granulation tissue was mixed with reactive new bone and callus formation in some area. This phenomenon is considered not so uncommon, which can be noticed easily in lateral flexion/extension view. Basically, this is a burst fracture with nonunion from ischemic necrosis and neurologic status should be carefully obserued.