title: Lipoma Arborescens of the Knee: Report of Three Cases and Review of the Literature.
abstract: Lipoma arborescens is a chronic, slow-growing, intra-articular lesion of benign nature, which is characterized by villous proliferation of the synovium, with replacement of the subsynovial connective tissue by mature fat cells. It usually involves the suprapatellar pouch of the knee joint. It is not a neoplasm but is rather considered a nonspecific reactive response to chronic synovial irritation, due to either mechanical or inflammatory insults. We report three cases of lipoma arborescens affecting the knee, the first in a young male without previous history of arthritis or trauma, the second in a 58-year-old male associated with osteoarthritis, and the final in a 44-year-old male diagnosed with psoriatic arthritis, which cover the entire pathologic spectrum of this unusual entity. We highlight the clinical findings and imaging features, by emphasizing especially the role of MRI, in the differential diagnosis of other, more complex intra-articular masses.
authors.affiliation: Department of Radiology, 424 General Military Hospital, Ring Road N. Efkarpias, 56403 Thessaloniki, Greece.
authors.forename: Ioannis
authors.identifier: 0000-0002-9792-5434
authors.initials: I
authors.lastname: Tsifountoudis
authors.affiliation: Department of Orthopaedics, 424 General Military Hospital, Ring Road N. Efkarpias, 56403 Thessaloniki, Greece.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Kapoutsis
authors.affiliation: Department of Orthopaedics, 424 General Military Hospital, Ring Road N. Efkarpias, 56403 Thessaloniki, Greece.
authors.forename: Anastasios-Nektarios
authors.initials: AN
authors.lastname: Tzavellas
authors.affiliation: Asclepios Diagnostic Center, 211 A. Papanastasiou Street, 54250 Thessaloniki, Greece.
authors.forename: Ioannis
authors.initials: I
authors.lastname: Kalaitzoglou
authors.affiliation: Asclepios Diagnostic Center, 211 A. Papanastasiou Street, 54250 Thessaloniki, Greece.
authors.forename: Apostolos
authors.initials: A
authors.lastname: Tsikes
authors.affiliation: Department of Orthopaedics, 424 General Military Hospital, Ring Road N. Efkarpias, 56403 Thessaloniki, Greece.
authors.forename: George
authors.initials: G
authors.lastname: Gkouvas