Lipoma arborescens in childhood: Case report and Systematic review of the literature

Lipoma arborescens in childhood: Case report and Systematic review of the literature

Introduction:
Lipoma Arborescens (LA) is a benign lesion of the synovium, characterized by proliferation of mature fat cells in the subsynovial layer, occurring more frequently in the knee joint. Clinical diagnosis is difficult due to the similarity to many other conditions, causing chronic effusion and restricted range of motion (ROM) of the joint.
We report a case report of a 9 year-old girl and undertake a systematic review of the literature.

Case report:
A 9 year-old girl presented to our clinic with left knee effusion and painful limitation of ROM. Plain radiograph and laboratory parameters were negative. MRI of the left knee showed nodular and frond-like villous proliferation of synovial tissue in the suprapatellar pouch without enhancement after contrast agent IV. The patient underwent an arthroscopical synovectomy and the histopathological analysis confirmed the diagnosis of LA. In a 36 month follow up the patient is asymptomatic without recurrence.

Systematic review
Search of PubMed, Google Scholar and Cochrane Database was performed using keywords related to LA and synovial lipomatosis. In total 170 papers were retrieved, which contained 406 reported cases (series and case reports). 211 were males and 195 females, while only 11 cases (2,7%) concerned children younger than 16. The main location of LA was the knee (84%). Treatment was reported in 216 cases and included arthroscopical synevectomy (52,3%), open synovectomy (41,2%) and conservative options (4,6%). 7 (3,2%) cases experienced recurrence, while no malignant transformation was reported.

Conclusion
LA should be considered, when diagnosing chronic intra-articular effusion. MRI is the gold standard among the imaging modalities due to lesion’s pathognomonic appearance. Arthroscopic (vs. open) synovectomy is a safe and effective therapeutic approach, because of minimal morbidity and early functional recovery with comparable low rate of recurrence.