Venolymphatic malformation (VLM) manifestation in the knee: An uncommon encounter

An uncommon congenital disorder known as venolymphatic malformation (VLM) of the knee develops from improper venous and lymphatic system development. It is a specific kind of vascular abnormality that affects lymphatic and veins, causing abnormal growth and dilation of these vessels. These types of malformations do not directly connect to the main channels but instead appear as swelling or other characteristic features depending on the specific type of malformation. Diagnosis can be particularly challenging when the skin covering the area appears normal. We present a 12-year-old male who presented with pain and swelling on the supra-patellar part of right knee for three months. He experienced some painonly during movements. Magnetic resonance imaging (MRI) and ultrasound were used for evaluation. It was confirmed that the patient had a VLM in the vastus medialis, vastus lateralis, and vastus intermedis muscles, intermuscular plane, and suprapatellar bursa region, along with a Morrant Baker cyst. The diagnostic modalities of MRI can be used with confidence to diagnose VLM swellings in the extremities.