False aneurysm of the external iliac artery caused by aseptic loosening and migration of a cemented cup.

A 79 year old woman with bilateral hip replacements presented with severe left thigh swelling, and life threatening hypovolemic shock. After adequate resuscitation, an angio CT scan of her pelvis showed a false aneurysm of the external iliac artery in proximity to a loose pegged cemented cup. A pelvic X-ray 6 years prior to presentation had revealed a medialized high riding pegged cemented cup with a loose cemented stem.