Bilateral lipoma arborescens of the subdeltoid bursa

Subacromial impingement by a lipoma arborescens

Subacromial impingement syndrome (SIS) is the leading cause of shoulder pain. A systemic approach for abnormal causes of SIS is recommended to avoid misdiagnosing rare or sinister pathologies. To our knowledge, only nine cases of subacromial lipoma arborescens associated with impingement syndrome have been reported in the literature. In this report, we briefly discuss histopathologic and radiological signs of an unusual case of impingement syndrome caused by subacromial "lipoma arborescens" and describe arthroscopic synovectomy after the failure of conservative management. The patient remains symptom-free five years after surgery.

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.

Lipoma arborescens of the knee

PURPOSE

Lipoma arborescens (LA) is a benign lesion described as replacement of mature fat cells with sub-synovial tissue, which causes the formation of villous projections. Underlying inflammatory conditions might predispose LA. This study demonstrates the treatment, post-operative survey and MRI demonstrations of this rare entity.

METHODS

Five patients (6 knees) diagnosed and treated with arthroscopic (5/6) and open (1/6) synovectomy were reviewed retrospectively. An additional mini-transquadricipital incision is used for excision of the extensive suprapatellar lesions. The patients had post-operative follow-ups at first and sixth months and then yearly. Radiographs and MRI of the affected knees were taken at the final follow-up.

RESULTS

The median follow-up was 59 (4-105) months. Major symptom was painless swelling of the joint. The presenting age was under 18 years in four patients. Recurrent lesions were detected in MRI scan of three patients with JRA, ARF and Tbc. Two out of three were located adjacent to the posterior capsule. The median of the Kujala questionnaire scores was 88 (74-95), and the median of the Knee Society Clinical Rating System scores was 95 (80-100) at the final follow-up.

CONCLUSIONS

Lipoma arborescens should be considered in the differential diagnosis of paediatric patients who have painless swelling of the knee joint. The lesion is totally curable. However, underlying persistent disease might aggravate the inflammatory process and might cause recurrent lesions. Although resecting the lesion adjacent to the posterior capsule of the knee joint is technically demanding, arthroscopic treatment is an effective procedure and transquadricipital approach may help resection of the extensive lesions in suprapatellar pouch.

LEVEL OF EVIDENCE

Case series, Level IV.

Bilateral lipoma arborescens with osteoarthritis knee: Case report and literature review

Lipoma arborescens is villous proliferation of synovium and is often unilateral in the absence of any systemic disease. We report a case of 54 year old male presenting with bilateral lipoma arborescens associated with osteoarthritis. The diagnosis is often difficult due to similar symptomatology of lipoma arborescens and osteoarthritis.

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

BACKGROUND

Primary lipoma arborescens (LA) is a rare, benign intra-articular hyperplastic tumor that has been associated with osteoarthritis (OA). The aim of this study was to determine whether prompt synovectomy could avoid progressive joint degeneration in cases of primary LA of the knee.

MATERIALS AND METHODS

A review of currently available literature about the disease was carried out. The clinical, histological and radiological records of a series of nine knees with primary LA diagnosed and treated between 2002 and 2012 were retrospectively reviewed. Eight of the knees had histological confirmation of LA and none had evidence of condropathy on the initial magnetic resonance image or degenerative changes at the initial radiographic examination.

RESULTS

At the final follow-up no evidence of OA was found in the three knees that underwent synovectomy when symptoms did not last more than 1 year. The five knees in which synovectomy was delayed developed progressive joint degeneration.

CONCLUSION

In this series, primary LA of the knee involved the development of early osteoarthritis when prompt synovectomy was not performed. Timely synovectomy is strongly recommended, if not mandatory.

LEVEL OF EVIDENCE

IV.

Lipoma arborescens associated with osseous/chondroid differentiation in subdeltoid bursa

Lipoma arborescens (LA) is a rare benign lesion of unknown etiology. It is characterized histologically by villous proliferation of the synovial membrane and diffuse replacement of the subsynovial tissue by mature fat cells. This condition affects the knee joint most commonly. Cases involving other locations including glenohumeral joint,[1] hip,[2] elbow,[3] hand[4] and ankle[5] have been rarely described. Involvement of the subdeltoid bursa has also been reported, but to date no case has described LA with osseous/chondroid differentiation of this bursa. Another significant finding in our case was the coexistence of LA with intermuscular lipoma, SLAP lesion and labral cyst.

Lipoma arborescens of the biceps tendon sheath

Lipoma arborescens, described as lipomatous infiltration and distention of synovial villi resulting in a frond-like appearance, most frequently affects the suprapatellar recess of the knee. While there have been reports of this entity involving the upper extremity joints, bursa, and tendon sheaths, we present the first reported case of lipoma arborescens isolated to the biceps tendon sheath. We describe imaging and histologic findings with clinical correlation.

Subdeltoid lipoma arborescens combined with rotator cuff tears

Lipoma arborescens, a rare benign intra-articular lesion, is characterized by lipomatous proliferation of the synovium in which the subsynovial tissue is replaced by mature adipocytes. Subdeltoid bursa is a rare location for lipoma arborescens, and only a few cases have been reported in the literature. This article reports 2 cases of subdeltoid lipoma arborescens combined with rotator cuff tears, and the possible relationships between subdeltoid lipoma arborescens and rotator cuff tears are discussed. The intra-articular villous proliferations on fat-suppressed T2-weighted magnetic resonance imaging appeared as yellowish-white lipomatous villous proliferations on arthroscopy, and finger-like lipomatous proliferation of the synovium, where the subsynovial connective tissue is replaced by mature adipocytes, on histology. Although further evidence would be necessary, the bony proliferations, in addition to bone-to-bone abrasion and inflammatory processes, may contribute to the relationship between subdeltoid lipoma arborescens and rotator cuff tears. Because this is a rare disease in a rare location, no established treatment guidelines are available for lipoma arborescens in subdeltoid bursa. For the current patients, arthroscopic excision of the lipoma arborescens and concomitant rotator cuff repair were prescribed after more than 6 months of conservative management. All patients had symptom relief and were satisfied with their results. Paying special attention to the radiologic and arthroscopic characteristics of the lipoma arborescens will help physicians and surgeons to achieve a more accurate diagnosis and effective treatment strategy, especially in patients with concomitant rotator cuff tears.

Bilateral lipoma arborescens of the knee: a case report

Lipoma arborescens, a diffuse articular lipomatosis, is a rare disorder characterized by marked villiform synovial proliferation and diffuse replacement of the subsynovial tissue by mature adipocytes. Unilateral joint involvement is the usual presentation while bilateral joint involvement is more uncommon. We reported a case of bilateral lipoma arborescens in a male patient with associated marked patellofemoral osteoarthritis and described the MR imaging findings.

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.

Polyarticular lipoma arborescens with inflammatory synovitis

Lipoma arborescens is a rare clinical condition characterized by mono or biarticular involvement of large joints, such as knees, hips, ankles, elbows, and shoulders. The aim of this case report is to describe an unusual case of lipoma arborescens affecting multiple large joints, mimicking rheumatoid arthritis. The patient, a 29-year-old woman had a history of intermittent arthritis of the wrists, knees, and ankles for at least 12 years. With the diagnosis of rheumatoid arthritis she had been on methotrexate (7.5 mg/wk) for the last 6 months along with different nonsteroidal anti-inflammatory drugs, without benefit. On physical examination a discreet joint swelling of the knees without effusion, gluteal muscle atrophy, and limited hip movements were observed. Laboratory tests presented normal acute phase reactants of inflammation as well as the rheumatoid factor, CK, and negative results for antinuclear, anti-DNA, anti-SSA/Ro, and anti-CCP (ELISA) antibodies. Magnetic resonance imaging of the knees and hips showed articular effusion and synovitis, and a pattern of lipoma arborescens. The histopathologic study confirmed the diagnosis. Knee arthroscopic synovectomy brought some improvement to joint mobility and pain.Although rare, this condition must be remembered in the presence of inflammatory arthropathy, particularly in the absence of response to clinical treatment, and absence of rheumatoid factor and anti-CCP antibodies, since the therapeutic strategy is radically different.

Lipoma arborescens of the glenohumeral joint causing bone erosion: MRI features with gadolinium enhancement

Lipoma arborescens is a rare benign intra-articular lesion that principally affects the knee joint. We present a case of lipoma arborescens involving the glenohumeral joint and associated with prominent large bony erosions. The gadolinium diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging (MRI) features of this lesion are also described. The characteristic MRI findings permit precise preoperative diagnosis of this rare condition even if it occurs in an atypical location and there are confusing radiological findings.

Lipoma arborescens of the glenohumeral joint: a possible cause of osteoarthritis

Lipoma arborescens is a very rare intra-articular lesion characterized by villous lipomatous proliferation of the synovium, usually involving the knee joint. To date, in the literature, there has been only one reported case of lipoma arborescens in the glenohumeral joint. But, the authors treated the patient conservatively and reported only the magnetic resonance imaging (MRI) findings. We report a case of a patient with lipoma arborescens involving the glenohumeral joint. To our knowledge, this is the first reported case of lipoma arborescens involving the glenohumeral joint managed by arthroscopic synovectomy. We identified reactive bone erosions and arthritic changes in the humeral head in a 22-year-old male patient by arthroscopy.