Lipoma Arborescens

Pigmented Villonodular Synovitis 176 Lipoma Arborescens 178 Synovial Osteochondromatosis 178 Synovial Hemangioma 179... 

Lipoma arborescens, also referred to as diffuse synovial lipoma or villous proliferation of synovium, is... 

Fig. 5.40a-c. Lipoma arborescens. a Transverse 12-5 MHz US image obtained over the lateral parapatellar recess of the knee shows an intra-articular relatively hyperechoic fronded mass (arrows) outlined by synovial effusion (asterisks). P, patella, b Transverse Tl-weighted and c fat-suppressed T2-weighted MR imaging correlation confirm the fatty nature of the frond-like projections of the mass... 

Davidson D, Letts M, Khoshhal K (2003) Pelvic osteomyelitis in children comparison of decades from 1980-1989 with 1990-2001. J Pediatr Orthop 23 514-521 Davies AP, Blewitt N (2005) Lipoma arborescens of the knee. Knee 12 394-396... 

Newman JS, Laing TJ, McCarthy CJ et al (1996) Power Doppler sonography of synovitis assessment of therapeutic response. Preliminary observation. Radiology 198 582-584 Nisolle JF, Blouard E, Baudrez V et al (1999) Subacromial-sub-deltoid lipoma arborescens associated with a rotator cuff tear. Skeletal Radiol 28 283-285... 

A variety of solid and cystic masses can be encountered around the knee as incidental findings. Most are benign, have an indolent behavior, such as lipomas, synovial and ganglion cysts, bursitis and neurogenic tumors, and can be easily diagnosed with US based on previously described criteria (Fig. 12.135). In the knee, however, there are some specific masses which merit particular attention. These include the lipoma arborescens and pigmented villonodular synovitis. In addition, an accessory muscle, the tensor fasciae suralis, can present as a pseudomass arising on the posterior aspect of the knee and warrants additional brief discussion here. 

Lipoma arborescens (from the word arbor meaning tree in Latin) is a rare benign intra-articular space-occupying lesion characterized by replacement of the subsynovial tissue by mature fat cells giving rise to a villous proliferation which is almost invariably found inside the suprapatellar recess (Ryu... 

Armstrong SJ, Watt I (1989) Lipoma arborescens of the knee. Br J Radiol 62 178-180... 

La S, Fessell DP, Femino JE et al (2003) Sonography of partialthickness quadriceps tendon tears with surgical correlation. J Ultrasound Med 22 1323-1329 Learch TJ, Braaton M (2000) Lipoma arborescens high-resolution ultrasonographic findings. J Ultrasound Med 19 385-389... 

Vilanova JC, Barcelh J, Villalon M et al (2003) MR imaging of lipoma arborescens and the associated lesions. Skeletal Radiol 32 504-509... 

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