Intra-articular post-traumatic ankle joint mass imitating localized pigmented villonodular synovitis (LPVS), the aid of ankle arthroscopy for diagnosis and treatment-a case report.

Intra-articular post-traumatic ankle joint mass is a rare entity that may mimic other pathologies, mainly localized form of pigmented villonodular synovitis (LPVS) regarding the clinical and imaging characteristics. We report the case of a 16-year-old female patient that presented an intra-articular ankle joint mass 8 months after an ankle joint sprain for which magnetic resonance imaging (MRI) suggested LPVS as possible diagnosis due to the presence of hemosiderin deposits. Diagnosis of a post-traumatic hematoma of her ankle joint was made via fine needle aspiration (FNA) biopsy and anterior ankle arthroscopy. At one-year-follow-up after the arthroscopic excision of the hematoma, the patient remained asymptomatic and pain free while MRI revealed no pathologic findings. This case demonstrates that LPVS is not always the diagnosis when hemosiderin deposits are depicted on the MRI of a solitary intra-articular mass. The FNA biopsy under direct arthroscopic view assists the diagnosis and guides the treatment plan in cases that no definite diagnosis has been reached preoperatively by MRI. Level of evidence IV, case report.

Localized Pigmented Villonodular Synovitis in an Unusual Location in the Knee: A Case Report / 대한정형외과연구학회지

Localized pigmented villonodular synovitis (LPVNS) is a rare lesion that can affect any joint, although it is most frequently found in the knee. When LPVNS affects the knee, it is usually a single mass of pedunculated appearance. We present a LPVNS occurred from the junction of the anterior horn of the lateral meniscus and the joint capsule in the knee. It detached and then moved at an unusual location, which caused pain, limitation of knee flexion and locking.

Localized Pigmented Villonodular Synovitis with Recurrent Subluxation of the Patella: A Case Report / 대한정형외과학회잡지

Pigmented villonodular synovitis is a slow, usually monoarticular, progressive proliferative disorder of uncertain etiology involving joint tissue, tendon sheath, and bursae. Pigmented villonodular synovitis has been divided in two forms-diffuse and localized. Localized pigmented villonodular synovitis of the knee joint can present with symptoms of pain, locking and instability. We report a case of a patient who presented with symptoms of recurrent subluxation of patella due to a localized pigmented villonodular synovitis occurring in the medial patellofemoral joint.

Localized Pigmented Villonodular Synovitis of the Posterior Compartment of the Knee: A Case Report / 대한정형외과학회잡지

Localized pigmented villonodular synovitis is a monoarticular proliferative condition that may affect any joint but is frequently found in the knee. The locaiized form was less frequent than the diffuse one. The estimated frequency of localized pigmented villonodular synovitis among patients performed an arthroscopic procedure was known one case lor each 2,500 cases. Previous reports pointed that the lower recurrence rate after the arthroscopic excision for localized form. We also experienced a case of localized pigmented viilonodular synovitis located at the posterior compartment of the knee, so we report this case with review of literatures.