| A rare primary bone dysplasia characterized by extensive epiphyseal, tarsal, spinal, and sometimes metacarpal and/or phalangeal stippling, severe generalized osteopenia, vertebral clefting, platyspondyly, bowing and shortening of the long bones, and variable periosteal cloaking. Laboratory analysis of lysosomal enzymes reveals normal activity. Histopathology shows numerous giant, multinucleated osteoclasts lining Howship lacunae, consistent with increased bone resorption. The condition manifests prenatally and is presumably lethal in the perinatal period. |