Cooked whole chicken has congealed blood around joints and bones, should I worry?
This exact thing happened to me about a month ago - roast whole chicken, bright red leaky blood around the bones and joints.

I looked it up back then.  I didn't find a truly authoritative source like the USDA, but I did find several instances of people saying that this happened even with highly overcooked chicken.  I also found several links similar to this one:

Bloody Chicken

The author (a Ph.D according to that page) did a number of experiments where he cooked a chicken and checked the internal temperature everywhere, ensuring that it was in fact pasteurized and thus free of any bacteria, and parts of it were still bloody on the inside.

According to him (and a few other sources I found), it's because the chickens are very young and their bones have not hardened properly; when you cook them, the marrow seeps out and ends up looking as you describe.

If you're using a meat thermometer to test the chicken for doneness, and you are certain that it got hot enough, then don't worry about the blood.  It's not appetizing, but it's not harmful either.

FWIW, I ate the chicken when it happened to me, and did not get the slightest bit sick.