Long bones of the legs are moderately bowed. Height and general health are normal. The vertebral bodies are dysplastic but not sclerotic. The iliac crests are abruptly flared, and the pelvic inlet distorted. Femoral capital epiphyses are flattened, with expansion of the femoral heads and coxa valga deformity.
Finger bones are undermodeled, with erosions and loss of joint space.
Overgrowth and distortion of the mandible and brow become evident in mid-childhood. Subsequently, entrapment of the cranial nerves leads to facial palsy and deafness. Life span is not compromised, stature is normal, and the bones are not fragile. Major x-ray features are widening and sclerosis of the calvaria, cranial base, and mandible. Endosteal thickening is present in the diaphyses of the tubular bones.