Intra-articular Lipoma Research Articles

Intra-articular lipoma of the hip joint – A report of two cases and literature review

Intra-articular lipoma of the hip joint – A report of two cases and literature review

A Hoffa’s fat pad lipoma mimicked patellar subluxation

A 44-year-old female presented with a 4-year history of gradual left knee pain, locking, and giving way. Despite consulting multiple doctors and receiving various treatments, her symptoms worsened. At presentation, clinical examination revealed a tender and swollen left knee joint with limited extension and a mild patellar popping during knee flexion. A knee ultrasound and MRI showed a 3 x 4 cm homogeneous solid mass within Hoffa's fat pad (HFP), consistent with a lipoma. The patient underwent surgical excision of the lipoma with complete resolution of symptoms and no recurrence at the 12-month follow-up. This case highlights the importance of careful evaluation and appropriate imaging for chronic knee pain not associated with trauma or overuse and the usefulness of joint ultrasound as a non-invasive diagnostic tool. MRI remains the gold standard imaging modality for intra-articular lipoma diagnosis and should be used to differentiate them from other intrinsic tumors, such as lipoma arborescens, pigmented villonodular synovitis, ganglion cysts, and to distinguish lipomas from liposarcoma.

Removal of a benign tumor in the knee by a combined approach in a patient with acute blockage of the joint: Case report

Soft tissue tumors are the most prevalent tumor lesions in the extremities, of which lipomas are the most frequent tumors in soft tissue, highlighting that these are benign conditions, despite being tumors, however, intra-articular cases are extremely rare, which contrasts with arborescent lipomas that are well described in the literature, which are secondary to degenerative processes in the knee and not neoplastic lesions. Intra-articular lipomas are rare, with the most common location being the knee, followed by the hip, lumbar spine, elbow, shoulder and wrist. Within the lipomas of the knee we find the arborescent lipoma, this is the product of degenerative changes established in the joint, which will be compromised and will give a manifest clinical appearance depending on its extension and size, which in turn will allow us to determine adequate management. surgical, in this case report we present a resection performed through arthroscopy and open approach due to a large lesion that generated joint blockage which subsides after the intervention.

A rare case of an intra-articular true lipoma of the ankle.

Most of the foot and ankle soft tissue tumors are benign. Although lipomas are the most common soft tissue tumors, intra-articular lipomas are an extremely rare entity. The majority of described cases of intra-articular lipomas occur in the knee joint. In particular, an intra-articular true lipoma of the ankle has not been reported. We report the case of a 45-year-old woman who presented with a progressively growing ankle mass over 5years, which started to restrict the range of motion. It was not preceded by any trauma or sports activity. On examination, a non-tender firm mass was evident on the lateral aspect of the right ankle joint with no signs of inflammation. It was non-compressible, non-mobile, and did not transilluminate. The clinical diagnosis was probable for a soft tissue ganglion. A radiograph revealed a soft tissue opacity over the anterolateral aspect of the tibiotalar joint. Magnetic resonance imaging (MRI) demonstrated a well-defined, multilobulated, encapsulated lesion located at the lateral aspect of the tibiotalar joint; with intra- and extra-articular components and an analogous signal intensity to fat. The patient underwent surgical excision of the tumor, and the histopathological examination showed mature adipose tissue representing an intra-articular lipoma. At the follow-up visit, the patient had complete resolution of symptoms and no active complaints. An intra-articular true lipoma of the ankle is an extremely rare tumor. MRI is an invaluable diagnostic tool to make a reliable diagnosis of intra-articular masses.

An Abnormality Within the Suprapatellar Pouch of a Cadaveric Donor: A Case Study

Introduction The suprapatellar pouch lies between the quadriceps tendon and the femur and contains synovial fluid from the knee. This structure, which communicates with one of the largest weight-bearing joints in the body, is prone to structural variation and pathology. Understanding and defining the various anatomical deviations and pathological conditions that arise within the suprapatellar pouch is critical in improving radiologic interpretation and in guiding treatment plans for patients with the all-too-common complaint of “knee pain.” Objective This report details an anatomic abnormality within the suprapatellar pouch of a cadaveric donor's left knee. The gross morphology and histologic features of this unusual finding are described in this abstract and are compared to the most likely differential diagnosis. Materials and Methods The decedent's medical history was obtained from the embalming report and death certificate. The dissection site was examined closely to evaluate the gross morphology of the lesion. The opposite knee was unavailable for evaluation due to its removal for a previous dissection. Tissue samples were collected and processed for hematoxylin and eosin staining. The slides were evaluated to obtain the histologic diagnosis. Results The decedent was a 79-year-old Caucasian female with a past medical history of unspecified lung cancer, hyperlipidemia, hypertension, and diabetes mellitus type 2. She had a recorded BMI of 43. She previously worked as a laborer in a textile factory. There was significant and diffuse edema noted in the embalming report, with no surgical or arthroscopic scars around the knee. Degenerative changes of the left femoral condyles were present. A fibrous web-like structure was observed within the left suprapatellar pouch that appeared to be in direct continuation with the synovial lining of the pouch. The diameter of each web-like strand ranged from 1.0 to 8.0 mm and the length of the structures varied from 0.5 to 7.0 cm. The histologic samples of the webbing demonstrated fibrous connective tissue with inflammatory cells and hypertrophied synovial lining. Additionally, infiltrative tissue was present within the posterior aspect of the pouch that was directly adherent to the web-like structure. The tissue within the suprapatellar pouch demonstrated villous projections of mature adipose with a distinct synovial lining surrounding it. Conclusions and Significance The macroscopic and histological findings of this lesion are most consistent with lipoma arborescence and intra-capsular fibrosis of the left suprapatellar pouch. This lesion is distinct from an intra-articular lipoma, which is characteristically a singular rounded mass and microscopically, has a thin fibrous layer without synovial lining. Although rare, an understanding of lipoma arborescence can help guide clinical decisions. Recognizing its features apart from that of lipoma is also crucial as the management between these two is different.

Large intra-articular true lipoma of the knee

BackgroundIntra-articular lipomas are rare and very few cases have been reported in the knee. To the best of our knowledge, here we report the largest lipoma to have ever been observed in the knee. It is crucial to avoid the misdiagnose of lipoma arborescens, which is associated with degenerative joint disease. Lipoma is a homogeneous, ovoid, adipose tissue tumor that is contained within a fibrous capsule and not associated with previous disease.Case presentationA 48-year-old male, with a soft-tissue tumor on the superomedial aspect of the right knee. Magnetic resonance imaging (MRI) revealed an intra-articular lipoma. The mass was resected by means of a limited arthrotomy.ConclusionsKnee lipoma is an extremely rare disease that must be diagnosed by MRI. Where possible, it should be resolved by arthroscopic resection.

US and MRI findings of Synovial Lipoma Arborescens of the hip: a case report

Lipoma arborescens is a rare intra-articular lesion consisting of villous lipomatous proliferation of the synovium that tends to occur in the knee joint, especially in the suprapatellar pouch. The lesion has been observed in other locations, including the glenohumeral joint, subdeltoid bursa, hip, and elbow. We report a case of a lipoma arborescens of a unilateral hip joint in a 62-year-old man. Ultrasonography and MRI were performed. In addition, a surgical synovectomy was performed and microscopic examination of the tumor revealed multiple variable-sized villous masses composed of mature fat tissue and lined by synovial cells which confirmed the diagnosis of lipoma arborescens. Synovial lipoma arborescens is a rare disorder of unknown etiology and is characterized by a villolipomatous proliferation of the synovial tissue. However, its association with chronic inflammatory disease such as a rheumatoid arthritis, degenerative lesions, or trauma is frequently reported. This case of lipoma arborescens was diagnosed by ultrasonography because MRI showed no difference between synovial osteochondromatosis and lipoma arborescens. On MRI, the signal of the lesion was similar to that of fat on T1-weighted, T2-weighted, and fat saturated images. The differential diagnosis includes intra-articular lipoma, synoval hemangioma, and synovial osetochondroma. On ultrasonography, the villous fatty projections of lipoma arborescens typically display echogenic pattern, similar to that of adjacent subcutaneous fat, and may undulate in real time within the surrounding effusion. The mass is usually soft in consistency and compressible.

Multifocal intraarticular lipoma arborescens of the hip and knee: A case report and review of literature

Lipoma arborescens (LA) is a rare clinical condition presenting mostly as an intra-articular lesion characterized by villous proliferation of the synovial membrane and hyperplasia of sub synovial fat. We report a case of a multifocal LA localized in the knees and the hips in a 20-year-old man symptoms being present for the last 3 years and initially mimicking an inflammatory arthropathy. On physical examination a discreet joint swelling of the left knee with effusion, and limited movements in the left hip were observed. Laboratory tests presented normal acute phase reactants of inflammation as well as the rheumatoid factor, CK, and negative results for antinuclear and anti-CCP (ELISA) antibodies. Magnetic resonance imaging of the knees and hips showed articular effusion and synovitis, and a pattern of LA. The histopathologic study confirmed the diagnosis. Arthroscopic synovectomy for the knee and open synovectomy for the hip brought some improvement to joint mobility and pain.Although rare, this condition must be differentiated from inflammatory arthropathy, particularly in the absence of response to clinical treatment, and absence of positive biochemical markers, since the therapeutic strategy is radically different.

Intra-articular lipoma arborescens of the knee: A report of two cases with bilateral localization

IntroductionLipoma arborescens is a very rare pseudo-tumoral lesion of unknown etiology, characterized by lipomatous infiltration of subsynovial stroma, bilateral involvement is exceptional, only eight cases are reported in the literature. Presentation of caseWe report the very rare case of two men presented at our department with complaints of swelling of both knees and intermittent joint effusion, Surgical biopsy revealed Lipoma arborescens in both cases. Open total synovectomy was performed. Follow-up evaluation showed no signs of recurrence. Discussion and conclusionLipoma arborescens is a rare entity, the unilateral form affecting the knee is the most common, with a predilection for suprapellar recess. Magnetic resonance imaging (MRI) is the examination of choice showing multiple villous proliferation of the synovium and fat-like cells, with a fatty signal on all sequences. Treatment by open or arthroscopic synovectomy offers the best outcomes.

An intra-articular synovial lipoma of the hip, possibly causing osteoarthritis: a case report and review of the literature.

In this report, we present the case of an intra-articular synovial lipoma in a 58-year-old female with a coincident marked unilateral hip osteoarthritis. This patient suffered from right hip pain that developed gradually over 2years. Physical examination noted decreased range of motion and evidence of impingement. MR and CT images showed an intra-articular fat-intense mass in the hip joint that was excised and confirmed as a synovial lipoma on histology. This case reveals that an intra-articular lipoma of the hip could be accompanied by pain or impingement and followed by hip osteoarthritis even in the absence of trauma.

Benign periarticular, bone and joint lipomatous lesions

Benign periarticular, bone and joint lipomatous lesions are rare entities that are increasingly being identified using current imaging techniques. This pictorial review illustrates the wide range of imaging presentations of these lesions at various sites and their pathognomonic features. The main lesions reviewed include intraosseous lipoma, liposclerosing myxofibrous tumour, lipoma arborescens and intra-articular lipoma.

Intra-articular lipoma of the hip

Intra-articular lipoma of the hip is a rare entity, with only two reports published in the English-language literature. We present a case of successful arthroscopic resection of an intra-articular peripheral...

Lipoma arborescens arising in the extra-articular bursa of the knee joint.

Lipoma arborescens arising in the extra-articular bursa of the knee joint is extremely rare. We describe an 11-year-old boy who complained of a gradual swelling mass of the lateral knee joint. Magnetic resonance imaging (MRI) showed a high signal intensity tumor on T1- and T2-weighted images with a thickened septa and nodular lesion that showed low signal intensity. The radiologist suggested the possible differential diagnosis of well-differentiated liposarcoma. At operation, the tumor was found under the iliotibial tract and was not in contact with the knee joint. Histopathologically, this lesion was diagnosed as lipoma arborescens arising in the extra-articular bursa of the knee joint. On MRI, the appearance of lipoma arborescens arising in the extra-articular bursa of the knee joint differed from that of conventional intra-articular lipoma arborescens. In this report, we describe a case of extra-articular lipoma arborescens of the knee joint bursa and discuss the diagnosis and etiology.

Intra-articular synovial lipoma in the posteromedial compartment of the knee

Intra-articular synovial lipoma in the posteromedial compartment of the knee

Knee Locking in Osteoarthritis due to Synovial Lipoma: A Case Report

Intra-articular synovial lipomas are very rare and only few cases have been reported till now. We are reporting a rare case of a unilateral intra-articular lipoma of osteoarthritic knee joint in a 62 years old male. Patient had two episodes of sudden locking of knee joint, which resolved spontaneously. A plain X-ray showed changes which were suggestive of osteoarthritis. Clinically, patient was diagnosed as a case of loose bodies in left knee joint. An arthrotomy was performed. After a Histopathological Examination (HPE) of loose bodies, a diagnosis of an intra-articular synovial lipoma was made. Due to wide differentials and varied clinical behaviour of loose bodies, lipoma should be included in differential diagnosis of osteroarthritic patients who complain of episodic locking of knees. Intraarticular lipomas, on arthroscopic guided excision, get cured permanently, with no recurrence. The differentiation of an intra-articular lipoma from a relatively more common entity, Lipoma arborescens, has also been discussed.

Intra-Articular Knee Mass in a 51-Year-Old Woman

A 51-year-old woman presented with moderate knee pain refractory to conservative measures. Radiographs revealed a well-defined, but irregularly-shaped ovoid soft tissue density at the posterior superior aspect of the infrapatellar fat pad of Hoffa. On magnetic resonance imaging, the mass was mildly heterogeneous and had intermediate signal in the proton density series and mixed signal intensity on the T2-weighted images. A low-signal rim could be seen around a portion of the lesion. Arthroscopic resection was performed and a vascular stalk was encountered. The differential diagnosis included: ganglion cyst, meniscal cyst, intra-articular lipoma, villous proliferation of the synovial membrane, Hoffa disease, and intracapsular chondroma. Histologic examination revealed a fibrous capsule partially surrounding a benign lipomatous neoplasm containing an abundance of thin- and thick-walled blood vessels with periadventitial myxoid stroma. To our knowledge, this is the first reported case of an intra-articular angiomyxolipoma in the literature. At 8-month follow-up, the patient was asymptomatic with no sign of recurrence. We postulate a low recurrence rate based on the insidious growth rate and benign histological appearance of such lesions. To our knowledge, no other intra-articular lipomatous lesion of the knee has been removed solely with arthroscopic techniques. Further follow-up information is needed to better understand the natural course of these lesions.

Intra-articular lipoma arborescens of the knee joint

Intra-articular lipoma arborescens (LA) is a rare entity that can present with monoarticular or polyarticular involvement of joints such as knees, ankles, hips, shoulders, and elbows. We describe a case in a 26-year-old man who presented with intermittent pain and swelling of the left knee joint for the previous 2 years. Physical examination showed only tenderness over the medial line of the left knee joint. MRI found only joint effusion; therefore, the patient was referred to the orthopedic clinic where he underwent arthroscopy, which revealed a diffuse yellow soft tissue synovial papillary growth involving both medial and lateral gutters of the suprapatellar pouch. A biopsy reported intra-articular LA. This is the first case of LA reported in Saudi Arabia. LA should be included in the clinical and radiologic differential diagnosis of cases with persistent knee joint effusion.

Bilateral Lipoma Arborescens of the Knee

Lipoma arborescens is a rare, benign intra-articular hyperplastic tumor characterized by villous, polypoidal, and lipomatous proliferation of the synovium. The knee is the most commonly affected joint1,2. Intra-articular lipoma arborescens is rare in adults3-7 and extremely rare in children5,8-11. The disease is typically considered to be a unilateral condition, and bilateral disease has been reported to be extremely rare, especially in children8-13. Patients usually present with chronic or recurrent painless swelling of the knee joint. Lipoma arborescens must be considered in the differential diagnosis of chronic joint effusions in childhood10. Our patient and his family were informed that data concerning the case would be submitted for publication, and they consented. A thirteen-year-old boy was admitted to our hospital because of chronic pain in the left knee. He had no history of trauma or infection. The left knee had been painful for four weeks during walking and running, thus limiting his daily activities. There were no locking symptoms. The patient’s medical history and the family history were unremarkable. The boy was healthy and had a body mass index of 21 kg/m2. Physical examination revealed bilateral swelling of the knee joints. Both knees had a normal local temperature and normal skin coloration and were not tender to palpation. Both joints were more voluminous than expected, and a mild joint effusion was present bilaterally. Full extension and 140° of flexion were possible in both knees, and knee motion did not elicit pain. There was no tissue mass around the knees, and no laxity could be detected. The results of blood tests, including measurements of the erythrocyte sedimentation rate, rheumatoid factor, C-reactive protein level, histocompatibility antigen B27 (HLA-B27), and antinuclear immunoglobulin, were normal. …

Supra-patellar swelling and knee instability

DiagnosisIntra-articular lipoma causing patellofemoral instability andsubluxation.DiscussionIntra-articular knee masses are rare, with an incidence ofonly 33 out of 2,200 knee arthroscopies described in theliterature [1]. Lipomas are common benign tumours, but anintra-articular localisation is exceptional. Two types oflipomatous entities can be found: solitary lipoma andlipoma arborescens. They differ in pathogenesis and grossappearance, although their microscopic features are similar.Lipoma arborescens, the more frequent of the two intra-articular tumours, is usually considered to be a secondarylesion, occurring in the context of either inflammatory ordegenerative joint disease, or after trauma [2–4]. Microscop-ically, lipoma arborescens is manifested as a diffuse hyper-plasic villous proliferation of the synovium in response tochronic irritation. Magnetic resonance imaging (MRI) exam-ination is pathognomonic, showing multinodular fatty tissueinfiltrating and protruding into the joint. The tissue showscontrast enhancement, and an effusion is often present.Solitary intra-articular lipoma is not associated with pre-existing pathology, and no causative factors can be identi-fied. Macroscopically, it is a soft yellow solitary mass, roundor ovoid in shape, uni- or poly-lobed, and finely encapsu-lated. It is usually small and often pediculated. It is thoughtto develop from the fat of the suprapatellar or retropatellarregions. On MRI the fatty signal shows increased intensity inT1 sequences and decreased intensity in all the sequenceswith saturation of the fat. There is no enhancement afterinjection of contrast medium.Seventeen cases of intra-articular lipoma of thekneewerefound in the international literature. This lesion is a rarecause of pain or internal articular dysfunction of the knee.Clinical presentation may vary from a simple palpable massto a more complex association of pain, swelling and internalderangement. There is a relationship between anatomicallocalisation and clinical presentation. Tumours of the supra-patellar region usually present as a simple palpable mass.However, localisation within Hoffa’s fat pad or between thefemur and tibia may have more varied manifestations, withpain, reduced range of motion and joint locking.Our case was an unusually large tumoral mass with apeculiar presentation. To our knowledge, it is the firstexample of patellofemoral instability with patellar sublux-ation due to intra-articular lipoma, although there has beenone previously reported case with perturbation of patellofe-moral tracking [5].

Solitary intra-articular lipoma locking the knee in a young boy

Intra-articular lipomas have been described in adult patients: only in five of them was it responsible for acute pain and locking of the knee. We report here the unique case of an 8-year-old boy with a painful locked knee caused by a solitary intra-articular lipoma in the anteromedial compartment of the knee.