Conclusion SLA has typical MRI features of villous， frond-like， or mound-like mature adipose tissue hyperplasia within the synovial membrane， and therefore preoperative MRI has an important diagnostic value.

    [KEY WORDS] synovial lipomatosis; shoulder joint; knee joint; ankle joint; magnetic resonance imaging; pathology， clinical

    滑膜树枝状脂肪瘤(LA)是一种罕见的良性疾病，也被称作滑膜脂肪瘤病、滑膜脂肪沉积与滑膜绒毛状脂肪瘤样增生等[1-5]。滑膜内显示绒毛状、棕榈叶状增生或弥漫性增生的成熟脂肪组织是其主要特征[1，6-9]。既往系统性地讲述该病的文献很少，大多是个案或少量案例的报道[10-19] ......