What causes burst veins and bruising behind your knees?

Age Pressure Reflux: Varicose veins of the lower extremities can have various sources. The varicose veins are a result of pooling of blood with increased venous blood pressure. The best way to close the varicose veins can be determined on physical exam and a focus venous ultrasound examination by a physician skill in treating venous disease. Check out the american venous forum or american college of phlebology.

Vein fragility: Popliteal veins are more thin walled and fragile with numerous interconnections. It is easily traumatized by clothing or sitting. Bending and hyperextension can cause vein obstruction & pressure.

Baker cyst: This is a common ailment. An ultrasound is definitive.