abnormal hardening or increased density of bone on radiographs, such as occurs with eburnation
. Osteosclerosis may accompany a great variety of disorders, including hyperparathyroidism
or renal osteodystrophy
, sickle cell anaemia
, Pagets disease
, systemic mastocytosis
, skeletal metastasis
In renal osteodystrophy the axial skeleton is the dominant site of involvement; the pelvis, ribs and spine are affected most commonly. Osteosclerosis of the vertebral bodies produces changes at both superior and inferior aspects, leading to an appearance termed the rugger jersey spine. In some cases epiphyseal sclerosis resembling the findings of ischaemic necrosis is evident.
Hodgkins disease may be characterized by osteosclerosis alone, osteolysis alone, or both of these together. Diffuse sclerosis of a vertebral body leads to an appearance termed ivory vertebral body.
In Paget's disease osteosclerosis may occur in both the active and the inactive stage. The inactive stage may be characterized by the alterations in the cranium (cotton wool appearance, thickening of the cranial vault, basilar invagination), spine (ivory vertebra, picture frame vertebral body), pelvis (thickening of the pelvic ring, focal or diffuse radiodense lesions), and long tubular bones (coarse trabeculae, widened and deformed bone). Table 1 provides a differential diagnosis of osteosclerosis.
Osteosclerosis, Table 1. Differential diagnosis of osteosclerosis.
|Skeletal metastasis||Mastocytosis||Myelofibrosis||Lymphomas||Paget's disease||Fluorosis||Renal osteodystrophy||Axial osteomalacia|
|Distribution||Axial > appendicular||Axial > appendicular||Axial > appendicular||Axial > appendicular||Axial > appendicular||Axial > appendicular||Axial > appendicular||Axial|
|Osteopenia or bone lysis||+||+||+||+||+||-||+||-|
|Osteophytisis, ligament ossification||-||-||-||-||-||+||-||-|