milo, do you have the davies book? that's a good resource to find where trigger points are located and what the different muscles are, etc. www.triggerpointbook.com according to davies (p. 20), trigger points range in size from a pinhead to a pea, although in a large muscle, like the thigh, it could feel like a lump the size of a thumb. you might be able to feel the knot, or lump, or you may not be able to feel it. however, you will feel pain when you press on a trigger point.