Z Orthop Unfall
DOI: 10.1055/a-0997-6959
Case Report/Fallbericht
Georg Thieme Verlag KG Stuttgart · New York

Lipoma arborescens – Uncommon Diagnosis for Joint Swelling: Case Report and Review of the Literature

Article in several languages: English | deutsch
Ralf Theermann
Gelenkchirurgie, HELIOS ENDO-Klinik Hamburg
,
Malte Ohlmeier
Gelenkchirurgie, HELIOS ENDO-Klinik Hamburg
,
Carl Heinz Hartwig
Gelenkchirurgie, HELIOS ENDO-Klinik Hamburg
,
Matthias Wolff
Gelenkchirurgie, HELIOS ENDO-Klinik Hamburg
,
Veit Krenn
Gelenkchirurgie, HELIOS ENDO-Klinik Hamburg
,
Caroline Liewen
Gelenkchirurgie, HELIOS ENDO-Klinik Hamburg
,
Mustafa Citak
Gelenkchirurgie, HELIOS ENDO-Klinik Hamburg
,
Thorsten Gehrke
Gelenkchirurgie, HELIOS ENDO-Klinik Hamburg
› Author Affiliations
Further Information

Publication History

Publication Date:
19 November 2019 (online)

Abstract

Introduction Soft tissue swelling of the knee joint can be caused by many diseases. Lipomas are one of the most reasonable differential diagnoses we have to consider. Therefore, we now present the uncommon case of a Lipoma arborescens (LA) and differentiate it from a quite similar manifesting spindle cell lipoma as follows.

Case Report A 49-years old patient reports about progressive knee pain for four years and observes an increasing joint swelling. This swelling is a soft tissue, shiftable tumour, not painful. The magnetic resonance imaging (MRI) with contrast agent brings the diagnosis of an advanced osteoarthritis of the knee joint and classifies the tumour as LA. Subsequently, we treat the osteoarthritis by implanting a total knee arthroplasty with simultaneous intraoperative tumour resection performed as total synovectomy. The histopathological processing confirms the clinically and radiologically made diagnosis of LA.

Summary Lipoma arborescens presents an uncommon subgroup of Lipomas, which is characterized by a slowly progressive increasing soft tissue swelling, especially around bigger human joints. Due to its intraarticular location, the LA might become clinically relevant when it reaches a certain tumour size. Looking at the diagnostics, sonography, MRI and especially the histopathological processing give the crucial results. Final proof can only be made by histopathological examination. Additionally, we have some differential diagnoses to exclude. Under these we predominantly find the spindle cell lipoma, synovial haemagioma, vascular synovial malformations and tenosynovial giant-cell tumour. Furthermore, an atypical lipomatous tumour should be excluded by FISH-analysis via determining the MDM2-Genamplification.