Keywords:
Arthritides, Diagnostic procedure, MR, Musculoskeletal system, Musculoskeletal joint
Authors:
R. Johnson, R. Chari, R. Chowdhury, R. Mansour, C. McCarthy, J. Teh; Oxford/UK
DOI:
10.1594/essr2016/P-0137
Background
Lipoma aborescens is a villous proliferation of the synovium whereby the subsynovial connective tissue is replaced by mature fat cells,
occuring most commonly in the suprapatellar pouch (Fig 1).
Other more unusual sites have however been described,
as demonstrated in this pictorial review.
Whilst a degree of subsynovial fatty infiltration is not an uncommon finding particularly in elderly patients,
more widespread fatty change is needed for the diagnosis.
In extensive disease,
the condition can be mistaken for tumour.
Lipoma aborescens is however thought to be a reactive process,
typically to a chronic inflammatory,
degenerative or traumatic insult,
rather than a true tumour.
1
The more unusual finding of a primary lipoma aborescens has also been described,
in the absence of a recognised underlying triggering factor (Fig 2).