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"What is this mysterious, perfectly circular, black and blue spot on my leg?"

ZocdocAnswersWhat is this mysterious, perfectly circular, black and blue spot on my leg?


It is a Perfect circle and purple/blue in color (Very dark). It appeared out of nowhere, and as it is a very significant bruise (and in an awkward area which is not easily bumped) it concerns me. It bulges outward from the leg which can easily be seen and felt, has a hard "knot" in the middle of it, and is very painful and tender to touch. I have also noticed new pain in my right foot and ankle. The bruise is fading out very slowly, and is still purple/blue around the outer edge and is now turning a bright red in the center. I have never had such a strange bruise with accompanying symptoms before-what do you think is going on? Thank you!


Thanks for your question. It is hard to say what is causing this specific bruise and the other associated symptoms that go with it. So it is important to speak with a doctor. The first thing that comes to mind is trauma, as you have discussed in your question. Usually, trauma and the associated injuries that go with it tend to happen in the parts of the body that are readily wounded. On the legs, this is often the front part of the lower legs, or the shins. On the forearms, it is the accompanying or synonymous area (ie, distal and anterior). That is because these areas are in regions of the body that are most prone to injury. Bruises and wounds to other body parts can obviously happen as well, but it does make doctors consider other things that can cause injury. For example, there are bites that can come from some spiders and wounds that can come from some toxins. Perhaps more common are other things that are happening on the inside and manifest themselves on the outside as bruises and spots. Purpura are one example of this, and there are many others. If you are having other symptoms, it is especially important to speak with your doctor. Please speak with your doctor.

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