I wore one this past winter and it kept my sore elbow warm. But it does add blood to the forearm which I found somewhat engorged it. So there were times I took it off because it bothered me. Seems like it works opposite of icing the joint.
So when I needed warmth from poor circulation/ cold conditions etc I used it. When the area was more inflammed and raw from abuse I iced. The brand I have are McDavid and they were like 12 $