Spontaneous rupture of a varicose vein due to thinning of the vein wall as it slowly has enlarged is a good reason to have the veins evaluated by ultrasound and treated to eliminate the problem veins. Swelling over a joint is also a reason to have this evaluated to avoid complications involving the knee.
You possibly have a a small hematoma which will probably heal with time. However if you have varicose veins it would be advisable to seek a consultation with a surgeon experienced in treating vein problems including an ultrasound examination. It is also possible that you have a knee injury which may require an orthopedic evaluation.
See a qualified phlebologist soon for evaluation of your veins. Rupture of small veins in the skin or fatty tissue of the legs usually means that there is very high pressure in the veins. Venous insufficiency, failure of the valves in many veins, causes most of these vein ruptures. The problem will only get worse without treatment.
I would recommend putting a pressure bandage or compression stocking on. You may want to have your varicose veins treated by a specialist to avoid recurrent problems. I would not be concerned of the bruising on your knee. It will go away with time.
Patients with varicosities can develop very friable (easy to rupture) varices called "blue blebs". These are susceptible to injury and rupture, usually while showering or bathing. When this happens, patients can become very scared by the amount of blood the can shoot out to the blood vessel. The first thing you should do is apply finger pressure (will instantly stop the bleeding), ask for help, raise your leg above your chest and apply a moderately tight bandage. Do not remove this bandage until you're seen by the doctor. After this emergency is cared for, you need to have a Venus Duplex study to have your veins mapped and then referred to see a surgeon for final treatment.
The pain and discomfort caused by varicose veins is just one of the many good reasons to get them checked. People often describe they feel like the veins burst and bruise. If you have those symptoms it is best to get them checked out by a vein specialist.
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