[Multiple stress fractures of the anterior and posterior pelvic ring with progressive instability. Description of a pronounced case with review of the literature].

We report a case of a 64-year old female patient, who developed a total instability of the pelvic ring within one year as a result of increasing insufficiency fractures. A minor trauma of the pelvis was assumed to be the trigger of this process retrospectively. The radiographic appearance of the multiple pseudoarthrosis simulated a metastatic disease. The differential diagnosis and the typical pattern of sacral insufficiency fractures (SIF) are described.