The results of dual x-ray bone densitometry in a patient with bilateral gluteal implants are presented. The patient underwent three measurements of the spine and hips, and one of them was before surgery. A baseline study showed mild osteopenia. After surgery, bone mineral density increased in both femoral necks, because of the superimposition of the implants. A spine phantom with and without a similar implant reproduced the findings in the patient. It is important to consider this type of surgery as a cause of potential bone mineral density artifact.