Osteopoikilosis

This is a 24 year female who presented with bilateral hip pain. A frontal radiograph of the pelvis was obtained which demonstrates innumerable sclerotic foci throughout the sacrum, pelvis, and proximal femurs. The lesions predominate in close proximity to the joints. The lesions are well defined with narrow zones of transition. There is no perisoteal reaction or evidence of cortical destruction. If just one of the lesions was seen in either the pelvis or femur, it would be called a bone island, also known as an enostosis. Bone islands are defined as they are named- they represent islands of cortical bone which are trapped in the medullary cavity. In fact, these lesions all represent bone islands in a disorder called osteopoikilosis. Osteopoikilosis is a benign skeletal dysplasia which is inherited in an autosomal dominant fashion. It is important to recognize so it is not confused for serious pathology.