Diagnosing Fibromyalgia
Because a lab test for FM is not available diagnosing FM is done using symptoms
and exclusionary factors. Guidelines developed by the American College of
Rheumatology (ACR) are most often used to diagnose FM. The ACR guidelines specify a FM
patient must have had widespread aching pain for at least three months and
register unusual tenderness under pressure at 11 of 18 points in the muscles
('tender points') around the body.
Widespread pain, as defined by the American College of Rheumatology, requires
having pain in both sides of your body and both below and above your waist, in
your lower back, part of your spine and your chest.
How effective the 1990 diagnostic criteria are has been a subject of debate.
Some physicians believe the criteria are arbitrary and will diagnose FM if not
all tender points are found. They believe it is more important to examine other
indices of widespread pain.
Exclusionary Factors. Because many of FM’s symptoms mimic those found in
disorders such as low thyroid activity (hypothyroidism), polymyalgia rheumatica,
neuropathies, lupus, multiple sclerosis and rheumatoid arthritis, these
disorders need to be excluded before a FM diagnosis is made. Your doctor may
have you take blood tests in order to rule out these disorders.
Tender Points Versus Trigger Points. FM patients may have two types of soreness;
tender points and trigger points, only one of which - tender points - are
diagnostic for FM. While tender points occur only in specific areas of the body
trigger points can occur anywhere. Trigger points are painful lumps or nodules
typically found in taut ropy bands that may twitch or jump when touched. Unlike
tender points they tend to restrict your range of motion.
The pain felt while pressing on a tender point is local while the pain felt upon
pressing a trigger point often ‘triggers’ pain elsewhere. A trigger point in the
shoulder, for instance, can trigger pain in the neck and the head. Trigger
points are diagnostic of a disorder called myofascial pain syndrome which often
co-occurs with FM. One study found that 75% of FM patients had trigger points.
An Under Diagnosed Disease. Like chronic fatigue syndrome FM is greatly under
diagnosed particularly among men. Dr. Clauw, a well known FM researcher and
physician, recently reported that men often recieve improper treatment for FM
because physicians tend to view complaints of pain in men as indicative of
inflammation rather than FM.
It is important, therefore, that people who think they have FM find a
knowledgeable doctor. Local FM support organizations or the FM Network can
assist you in finding one.
The Phoenix Rising website is compiled by a layman. It is not a substitute for a physician and is
for informational uses only. Please discuss any information in these pages with
your physician.