Multiple symmetrical lipomatosis (MSL), known also as benign symmetrical lipomatosis, Madelung's disease and Launois-Bensaude disease, is a rare condition first described by Brodie in 1846 and subsequently classified by Madelung and Launois. Its present descriptive name was introduced by Enzi .
MSL is rare in the UK and most prevalent in middle-aged Mediterranean males. The dominant clinical feature is painless fat accumulation around the neck, upper back and shoulders. Patients may become symptomatic due to compression of the great vessels and trachea and require surgery. Further manifestations include haematological, metabolic and hepatic disturbances and these are exacerbated by concomitant alcoholism.
Kazumi  described a mitochondrial defect leading to alteration of lipolysis in brown fat, the distribution of which is similar to the peculiar position of lipomas in MSL.
MRI  helps to determine the extent of the fat accumulation prior to possible surgical resection and also confirms the fatty nature of the subcutaneous masses. A liposarcoma may be identified by an alteration in the otherwise homogeneous MRI signal or by non-suppression in STIR sequences. Cushing's syndrome, which also shows excess fat deposition, is characterised by abnormal biochemisty and osteoporosis.
Osteonecrosis has not been described in MSL previously, however there are multiple associations of altered lipid metabolism and osteonecrosis. Bone infarctions are a recognised complication of hypercortisolism, pancreatitis, diabetes mellitus, alcoholism, and gout as well as haemoglobinopathies, collagen small vessel disease and Caisson disease .
Jones  examined the relationship of osteonecrosis with different clinical disorders characterised by defective lipid metabolism and suggested a common pathway of continuous or intermittent intraosseus fat emboli leading to focal intravascular coagulation and resulting in osteonecrosis.
Multiple symmetrical lipomatosis with extensive osteonecrosis has not been described previously and the present case might widen the differential diagnosis of bone infarction.