Solitary sclerotic bone (osteosclerotic or osteoblastic) lesions are lesions of bone characterised by a higher density or attenuation on radiographs or computer tomography compared to the adjacent trabecular bone. However, a specific density range has not been specified for those terms ¹.

Differential diagnosis

The differential diagnosis of solitary sclerotic bone lesions can be narrowed down according to the following factors ^1-3:

• aggressive features

• history of malignancy

• ground glass appearance

• cartilaginous matrix (rings and arcs appearance)

• typically benign entities

Concerning the above factors the differential diagnosis includes the following lesions ^1-3:

• presence of aggressive features

  • sclerotic bone metastasis: might be solitary because no others are present or have been imaged

  • osteosclerosing myeloma ⁴

  • chondrosarcoma

  • osteosarcoma

  • infection: e.g. sclerosing osteomyelitis of Garré

  • callus

• history of malignancy

  • sclerotic bone metastasis

  • osteosclerosing myeloma

• ground glass appearance

  • fibrous dysplasia

• cartilaginous matrix

  • enchondroma

  • chondrosarcoma

• typically benign entities

  • bone island

  • non-ossifying fibroma

  • osteoma

  • bone infarction

  • sclerosing bone dysplasia

Practical points

• aggressive features →  might require an oncological referral and/or biopsy ¹

• history of malignancy →  will almost always require additional imaging, follow-up or oncologic referral

• high CT attenuation values might help in the differentiation of bone island from osteoblastic metastases ⁵ but attenuation values should not be used exclusively for the assessment of sclerotic bone lesions ⁶

See also

• solitary sclerotic bone lesion

• solitary mixed density bone lesion

• low T1 solitary bone lesion