Bone & joints
Other nonneoplastic
Synovial lipomatosis
Authors: Charanjeet Singh, M.D., Vijay Shankar, M.D.
Last author update: 1 June 2013
Last staff update: 6 December 2023
Copyright: 2002-2024, PathologyOutlines.com, Inc.
PubMed Search: Synovial lipomatosis
Table of Contents
Definition / general | Terminology | Epidemiology | Clinical features | Case reports | Treatment | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) imagesCite this page: Singh C, Shankar V. Synovial lipomatosis. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/jointssynoviallipomatosis.html. Accessed December 26th, 2024.
Definition / general
- Pseudotumor of synovium with distinct histomorphology, possibly due to inappropriate fat deposition and degenerative articular diseases of joints (J Lab Physicians 2011;3:84)
Terminology
- Also called Hoffa disease, villous lipomatous proliferation of synovial membrane, diffuse lipoma of joint, lipoma arborescens
- Not a WHO diagnosis
Epidemiology
- Rare
- Older patients, usually male, associated with joint trauma, degenerative joint disease and chronic arthritis
Clinical features
- Rare; usually knee but may occur in any joint
- Unknown etiology
- Men are commonly affected with pain and swelling of joint
- MRI is useful in diagnosis (Radiol Med 2005;109:540)
Case reports
- 24 year old man with lipoma arborescens affecting multiple joints (Skeletal Radiol 2005;34:536)
- Lipoma arborescens of the knee (Knee 2005;12:394)
Treatment
- Arthroscopy and excision
- May recur since often is a reactive process
Gross description
- Enlargement of infrapatellar fat pad with pain in anterior compartment of knee; synovium is papillary, yellow and fatty
Gross images
Contributed by Mark R. Wick, M.D.
Microscopic (histologic) description
- Synovial hyperplasia with unremarkable fat extending to synovial lining; occasional chronic inflammatory infiltrate
Microscopic (histologic) images
Images hosted on other servers:
Villi-like structures
Papillary architecture
Mature adipocytes
Focal hyperplasia
Few mature lipocytes
