I have had them off and on. Was told it is damage to my vascular system from the lupus

Does it look like bruising because it may be that. I suffer from bruising and it sometimes is like a blue colour on me because of my skin colour is black and dark and I get it all over my body mainly my thighs, knee, legs, shoulders and back all over just use Deep Relief Gel and Ibuprofen and Levomenthol on it it helps me because it can be sometimes painful and hurt or I use E45 or Lavender Oil. Hope you find out what it is and can do something to help you with the problem.

I was just reading an article on livedo reticularis and livedo racemosa- both caused by swelling of the vasculature. There is also leukocytoclastic vasculitis that can cause purple spots. Maybe it's not exactly what you're describing but it helps to look at images online just to compare I think.

Oh yes, I have blue knees and someone's elbows. Mine is a circulation problem related to Raynaud's.

I still believe it is bruising which is one of the symptoms for SLE Lupus which is in the literature and I have also been told by my Rheumatologist.