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Pigmented villonodular synovitis causing painless chronic knee swelling in an adolescent
1Department of Pediatrics, Sports Medicine and Adolescent Medicine Division, Eastern Virginia Medical School, Norfolk, Virginia 23507, USA. jsbrenner@aap.net
Clinical Pediatrics
|April 10, 2007
Summary
A painless chronic knee effusion in adolescents is rare and requires a broad differential diagnosis. Pigmented villonodular synovitis is an uncommon cause, diagnosed with imaging and biopsy, and treated with synovectomy.
Area of Science:
- Orthopedics
- Pediatric Rheumatology
- Pediatric Oncology
Background:
- Painless chronic knee effusions in adolescents are uncommon and typically not associated with trauma.
- Differential diagnosis includes common causes like internal derangement and uncommon conditions such as juvenile rheumatoid arthritis and pigmented villonodular synovitis.
Observation:
- This case highlights an adolescent presenting with a chronic, painless knee effusion.
- The diagnostic process involved evaluating various rare conditions affecting the knee joint.
Findings:
- Pigmented villonodular synovitis (PVNS) is a rare cause of chronic knee effusion in adolescents.
- Diagnostic tools like plain radiographs, magnetic resonance imaging (MRI), and biopsy are crucial for differentiating PVNS from other conditions.
Implications:
- Early and accurate diagnosis of PVNS is essential for appropriate management in adolescents.
- Treatment options, including arthroscopic or open synovectomy, aim to remove the affected synovial tissue.
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