Sclerotic lesions are rare in malignant monoclonal gammopathies, although they are occasionally associated with POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy and skin changes). In most cases, osseous lesions in POEMS syndrome present as an isolated sclerotic deposit or a combination of both lytic and sclerotic lesions. Diffuse osteosclerosis is extremely rare and may lead to the diagnosis of multiple myeloma, classically known to present as lytic lesions in the skeleton, with or without diffuse osteoporosis. We report a 74-year-old woman with widespread and substantial osteosclerotic lesions, associated with IgA- myeloma, and with no other criteria for POEMS syndrome, and who was rapidly diagnosed with compression of the spinal cord. Detailed knowledge of imaging features in myeloma emphasises the need to consider plasma cell neoplasm in the differential diagnosis of any pattern of bone sclerosis. Although exceptional, multiple myeloma must be borne in mind in the presence of diffuse bone sclerosis.