Primary lipoma arborescens of the knee may involve the development of early osteoarthritis if prompt synovectomy is not performed

Lipoma arborescens with patellofemoral osteoarthritis and genu valgum

Lipoma arborescens is a rare benign intra articular lesion characterized by lipomatous proliferation of the synovium. The condition typically affects the knee presenting with atraumatic pain and swelling. It should be considered in the differential diagnosis of monoarthritis and joint effusion. Diagnosis is made on MRI with characteristic features. We present a rare case of lipoma arborescens with patellofemoral osteoarthritis and genu valgum. We discuss the clinical presentation, radiological findings, and management.

Lipoma Arborescens: A rare cause of knee swelling

Introduction

Lipoma Arborescens is a chronic, slow growing intra articular lesion of benign nature which is commonly seen in the supra patellar region of the knee joint. It is characterised by villous proliferation of the synovium, with the replacement of the subsynovial connective tissue with fat cells. It is not a neoplasm but non-specific reactive response to chronic synovial irritation, due to mechanical or inflammatory insults. We highlight this condition to raise awareness to be kept as a differential diagnosis in knee joint affected by various slow, progressive chronic inflammatory conditions.

Case Report

We present case of 51-year female with severe knee swelling since 3 to 4 years with episodes of remission and regression on and off. She was diagnosed with lipoma arborescens after magnetic resonance imaging and confirmed after post operative histology.

Conclusion

We in this case study highlight this rare condition with its imaging characteristics and arthroscopic treatment. Keeping in mind that lipoma arborescens though benign in nature and as one of the rare causes for knee swelling, has to be treated to get an optimal outcome.

Evaluation and Management of Intra-Articular Tumors of the Knee

Intra-articular tumors of the knee are most commonly benign. Overall, this is a relatively rare clinical presentation. The differential diagnosis includes pigmented villonodular synovitis, synovial chondromatosis, lipoma arborescens, synovial hemangioma, and very rarely primary sarcoma (synovial sarcoma being the most common). The clinical presentation for these conditions is usually non-specific, but radiographic and advanced imaging findings are able to differentiate some of these tumors. It is essential to obtain and send tissue specimens to pathology for histologic analysis to rule out a primary malignancy as a missed diagnosis can have grave implications on patient outcomes. This review summarized key aspects of diagnosis and treatment for these conditions.

Incidental Intraoperative Finding of Bilateral Lipoma Arborescens in a Patient Undergoing Bilateral Total Knee Replacement

Lipoma arborescens (villous lipomatous proliferation of the synovial membrane) is a rare, benign articular lesion characterized by diffuse villous proliferation of the synovium with mature fat substitution of the sub-synovial connective tissue. The etiology of this condition still remains unknown. It represents part of differential diagnosis for a progressive swollen knee with chronic pain secondary to synovial proliferative disorders with or without associations with osteoarthritis. We report an intraoperative finding of lipoma arborescence in a patient who underwent bilateral primary total knee replacement secondary to advanced osteoarthritis.

Femoral osteochondroma responsible for ischiofemoral impingement, bursitis, and secondary lipoma arborescens mimicking malignant transformation

We present the case of a 53-year-old woman with a known history of hereditary multiple exostosis disease referred for further imaging work-up after ultrasound and computed tomography leading to the suspicion of malignant transformation of an osteochondroma (exostosis) located on the posteromedial aspect of the right proximal femur. Imaging examinations suggested an ischiofemoral impingement resulting in a secondary bursitis associated with the development of an internal lipoma arborescens. This rare association explained the complexity of the diagnosis. Magnetic resonance imaging (MRI) played a key role in correctly identifying this benign complication of the osteochondroma and in distinguishing those observations from a secondary exostotic chondrosarcoma. MRI findings were subsequently confirmed at surgery and pathological examination.

Bilateral lipoma arborescens -A proliferative case demonstrating progression in an adolescent male

Case

We describe a case of extensive symptomatic bilateral lipoma arborescens of the knee in a 19-year-old man who suffered from recurrent knee effusions for many years. This patient had MRI evidence of progression of disease prior to arthroscopic intervention. He was treated with bilateral complete arthroscopic synovectomies, demonstrating no evidence of cartilage wear.

Conclusion

Lipoma arborescens is a progressive disease. Timely diagnosis and treatment may prevent disease evolution and sequela.

Medical image analysis of knee joint lipoma arborescens and arthroscopic treatment

OBJECTIVE

Arthroscopy is a minimally invasive surgical procedure on a joint in which examination and treatment of knee damage is performed using a surgical device known as the arthroscope. Lipoma arborescens (LA), an infrequent intra-articular lesion, originates from mature adipose cells under subsynovial tissue. The synovial membrane is pale yellow with large villous projections. It is caused by various underlying factors. We found many patients with LA and processed them appropriately.The research was implemented to investigate therapeutic effect of semi-automated arthroscopic diagnosis and treatment for knee joint.

METHODS

We used the Stryker arthroscopic in surgery that is 4 mm in diameter with angle at 30°. Patients were chosen by biomechanical analysis and scanning mode. All of the patients underwent radiographic imaging examination, Magnetic Resonance Imaging (MRI), Lysholm Score and Visual Analogue Scale (VAS). Arthroscopic limited synovectomy was carried out on these patients.

RESULTS

The wound of all patients healed up. The content of follow-up includes: chief complaints, range of motion of knee joint, Visual Analogue Scale (VAS) and Lysholm score. No swollen nor effusion of the infected knee was found in all patients during the follow-up. The postoperative symptom was markedly alleviated in fourteen patients and partially alleviated in one. All patients were satisfied with the therapeutic effect.

CONCLUSION

We performed biomechanical analysis based on knee slight flexion and extension. Arthroscopy is an endoscope for the diagnosis and treatment of joint diseases. Semi-automated arthroscopic debridement is good for early and mid-term osteoarthritis with Lipoma arborescens.

Lipoma Arborescens - Eyes See What Mind Knows!

Introduction:

Lipoma arborescens is a rare lesion, benign in nature and was first described in detail in 1957. <200 cases have been reported in the literature by now. It consists of subsynovial villous proliferation of mature fat cells. Since the incidence of the condition is very rare, definite etiology has not established. Arthroscopic or open synovectomy has been the treatment of choice of the lesion.

Case Report:

We present you a case of lipomatosis arborescens of the right knee in a 28-year-old male. The magnetic resonance imaging images showed high signal intensity villous or nodular foci on both T1- and T2-weighted images which were indicative of fat globules. They were predominantly found in huge number in suprapatellar pouch. The patient underwent arthroscopic synovectomy showing numerous broad- based polypoid or thin papillary villi composed of fatty tissue. Approximately 40 cc of lobulated globules were removed, and some were sent to histopathology which confirmed the presence of benign synovial tissue and fragments of adipose tissue present beneath the synovial surface. On 1-year follow-up, the patient was free of pain and devoid of any mechanical symptoms.

Conclusion:

Hence, we conclude that this is a rare entity that needs early intervention to prevent progressive joint degeneration and has excellent patient satisfaction with arthroscopic debridement with very low incidence of recurrence.

Primary lipoma arborescens of the knee

Lipoma arborescens is a rare and benign intra-articular lesion of unknown etiology; it is characterized by synovial villous proliferation and sub-synovial connective tissue replacement by mature fatty tissue. It is part of the differential diagnosis in patients with an articulation affected by a slow, progressive, and chronically inflamed affection. We report primary knee involvement in a patient without significant articulate antecedents. Lipoma arborescens was diagnosed after knee magnetic resonance imaging and was confirmed by an anatomopathological study of the surgical specimen.

Isolated peroneal tenosynovial lipoma arborescens: multimodality imaging features

Synovial lipoma arborescens is a rare and benign fatty proliferative lesion of the synovium that is most commonly seen within the suprapatellar pouch of the knee, but increasingly reported to involve tendon sheaths, including those of the ankle. We present the third known case of tenosynovial lipoma arborescens isolated to the peroneal tendon sheath without ankle joint involvement. To our knowledge, this is the first to report this entity utilizing a unique combination of radiographic, sonographic, and MR imaging, along with intraoperative and histologic correlation. Knowledge of this case is important when interpreting radiographic or sonographic images of this condition to raise the possibility of the rare entity of lipoma arborescens involving the peroneal tendon sheath.

Lipoma arborescens of the elbow: a case with features of a high-grade tumor

Lipoma arborescens (LA) is an uncommon non-neoplastic disorder that may affect almost any joint, mainly the knee. LA is very rare in the elbow, and there are only a few cases reported in the literature. This study aimed to describe a case of LA in the elbow, presenting with features of a high-grade tumor. The authors report the case of a 51-years-old male who presented to this institution with pain and swelling on the left elbow. The patient had a seven-year history of investigation, with inconclusive diagnosis. Magnetic resonance imaging (MRI) showed an expansive mass with local aggressiveness. Due to these characteristics, it was not possible to discard soft tissue sarcoma at the differential diagnosis. After biopsy and a multidisciplinary team meeting, the authors opted for surgical resection. The final anatomopathological result confirmed the diagnosis of LA. Despite not being a true neoplasm, LA can cause many symptoms and functional impairment of the affected joint. It is important to keep this diagnosis in mind when any expansive mass surrounding a joint is observed.

Spectrum of Fat-containing Soft-Tissue Masses at MR Imaging: The Common, the Uncommon, the Characteristic, and the Sometimes Confusing

Fat-containing tumors are the most common soft-tissue tumors encountered clinically. The vast majority of fat-containing soft-tissue masses are benign. Lipomas are the most common benign fat-containing masses and demonstrate a characteristic appearance at magnetic resonance (MR) imaging. Less common benign soft-tissue masses include lipoblastoma, angiolipoma, spindle cell lipoma/pleomorphic lipoma, myolipoma, chondroid lipoma, lipomatosis of nerve, lipomatosis, hibernoma, and fat necrosis. Well-differentiated liposarcomas (WDLPSs)/atypical lipomatous tumors (ALTs) are locally aggressive soft-tissue masses that do not metastasize. Biologically more aggressive liposarcomas include myxoid, pleomorphic, and dedifferentiated liposarcomas. At MR imaging, lipomas typically resemble subcutaneous fat but may contain a few thin septa. The presence of thick, irregular, enhancing septa and nonfatty soft-tissue mass components suggests liposarcoma rather than lipoma. However, benign lipomatous lesions and WDLPS/ALT often have overlapping MR imaging findings. Distinguishing WDLPS/ALT from a benign lipomatous lesion or from fat necrosis at imaging can be challenging and often requires histologic evaluation. We present the spectrum of fat-containing masses, using the World Health Organization classification of adipocytic tumors, with an emphasis on commonly encountered lesions, characteristic MR imaging findings associated with specific tumors, and overlapping MR imaging findings of certain tumors that may require histologic sampling. We also briefly discuss the role of molecular markers in proper characterization and classification of fat-containing soft-tissue masses. (©)RSNA, 2016.

Lipoma Arborescens of the Knee: Report of Three Cases and Review of the Literature

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.

Lipoma Arborescens: Review of an Uncommon Cause for Swelling of the Knee

Lipoma arborescens is a rare cause of chronic monoarticular arthritis, with only a few cases reported in the literature. It is most commonly seen in the knee, but cases in other joints such as the wrist, shoulder, and elbow have also been described. It is a benign condition, in which the subsynovial tissue is replaced diffusely by mature fat cells. We describe a case involving the knee and discuss the symptoms, diagnosis, and treatment.