Age / Sex : 53 / F

Pigmented villonodular synovitis (PVNS)

Discussion

Findings:

Simple : Right shoulder lateral oblique view shows mild sclerotic change at lateral aspect of axillary margin of scapula.

MRI : There are T1WI & T2WI intermediate SI, extensive lobular synovial proliferation with low SI foci at the glenohumeral joint, extending to subcoracoid recess. Humeral head shows subchondral cystic defects with bone marrow edema at the anterolateral aspect.

Differential Diagnosis:

Synovial chondromatosis

Diagnosis:  

Pigmented villonodular synovitis (PVNS)

Discussion:

Locally destructive fibrohistiocytic proliferation, characterized by many villous and nodular synovial protrusions, which affects joints, bursae, and tendon sheath.

Epidemiology

-Predominantly in early to middle age (2nd to 5th decades)

-No gender predilection (intraarticular)

-Slight female predominance (extra-articular disease)

Clinical presentation

-Joint swelling, pain and occasionally joint dysfunction

Location

-knee (by far the most frequently affected joint ): 66-80%

-hip: 4-16%

-ankle, shoulder, elbow, spine, other joints 

Classification

-Localized (discrete intraarticular mass): most common and usually extra-articular (PVN in bursa  and PVN in tendon sheath)

-Diffuse (involves all of the contiguous synovium): most common form of an intra-articular disease. 

Treatment

-Surgical open or arthroscopic synovectomy, external beam radiotherapy

References:

Adam Greenspan, Javier Beltran: Orthopedic Imaging 6th edition

Murphey MD et al: Pigmented villonodular synovitis: radiologic-pathologic correlation. Radiographics. 28 (5): 1493-518.