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 doctors
">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.