Pigmented Villonodular Synovitis
What is it? Pigmented villonodular synovitis (PVNS) is a joint problem that usually affects the knee or hip and is caused by abnormal growth of the synovial lining.
How does it present? The patient may notice pain, swelling and stiffness of the knee. Occasionally a "popping" sensation may occur if the PVNS growth is affecting joint movement. Symptoms may wax and wane over time and may develop gradually.
Common exam findings: Exam finding may show an effusion and exam finding similar to those of a meniscal injury can be seen if the growth is affecting movement of the joint. Otherwise, findings may be nonspecific.
Tests and treatment: Knee x-rays may be done, but often a magnetic resonance imaging (MRI) is needed to help with diagnosis. Biopsy and surgical treatment may be needed. Surgical intervention includes a synovectomy.