Osteitis condensans ilii is a term applied to the alteration of the bony architecture of the iliac bone adjacent to the sacroiliac joint. The condition is characterized by condensation of the involved bone without involvement of the joint space or adjacent sacrum. During the year 1943, 23 patients presenting these changes were seen in the clinic. Since the condition has been described infrequently, a study of the clinical manifestations was undertaken to determine whether a clinical syndrome accompanied or produced this roentgenographic change. A review of the literature relative to osteitis condensans ilii revealed that the first article appeared in 1926, at which time Sicard, Gally and Haguenau1 reported 5 cases, describing accurately the roentgenograms. They stated that they did not know the etiology. In 1928 Bársony and Polgár2 in an article on the condition were not sure that it was a clinical syndrome but described the changes