It can be confusing to talk about fibromyalgia tender points and myofascial trigger points, especially since a lot of people (even medical folks) use the term trigger point for both of them. They've typically been regarded as different things, but new research is looking at whether they're actually the same -- at least, in some of us.

First, some quick definitions:

Tender Point: 18 designated spots on the body (9 pairs) that are abnormally painful when a small amount of pressure is applied. Doctors use them to diagnose fibromyalgia (FMS). (See image, top right.)

Trigger Point: A small, hard knot of tissue that typically forms after trauma. The knot is often painful, especially when poked, but it may also cause pain in another area (called referred pain.) The electrical activity (from nerves) in trigger points is abnormal.

Myofascial Pain Syndrome (MPS): People with this condition have chronic pain from trigger points. It's common for people with MPS to later develop fibromyalgia. MPS may also be misdiagnosed as FMS, especially because it can be hard to trace referred pain to its cause.

Research recently published in The Journal of Pain examines whether FMS tender points are actually myofascial trigger points. In 30 people with FMS, they looked at the electrical activity in tender points and found that most tender points actually were trigger points. When researchers pushed on the trigger points, the referred pain mimicked FMS pain.

They're not saying that FMS is the same thing as MPS, but they are saying trigger points are more important than has been thought, and they're saying that trigger points should be treated in people with FMS.

Source: About.com