Fibromyalgia is a chronic health condition that involves widespread pain throughout your body, tenderness in certain areas, and fatigue.
It can be difficult for your doctor to diagnose fibromyalgia. There are no lab tests or imaging tests available for it. Instead, your doctor will ask you to describe and rate your symptoms.
A number of other conditions can have similar symptoms as fibromyalgia, including:
- Lyme disease
- certain types of cancer
- degenerative diseases of the spine
Your doctor can use clinical tests to rule out many of these conditions. But doing so takes a lot of time, effort, and money. According to the National Fibromyalgia and Chronic Pain Association, it takes an estimated 5 years on average for a patient with fibromyalgia to get a proper diagnosis.
In 2010, the American College of Rheumatology endorsed a new set of criteria for diagnosing fibromyalgia. They published those criteria in the journal Arthritis Care and Research.
According to those criteria, you have fibromyalgia if you meet the following three conditions:
- You have a widespread pain index (WPI) score of seven or higher and a symptom severity scale (SS) score of five or higher. Or you have a WPI score of three to six and a SS score of nine or higher.
- You’ve experienced symptoms at a similar level for at least 3 months.
- You don’t have another disorder that could explain your symptoms.
Before these criteria were adopted, doctors used a “tender point” system to diagnose fibromyalgia. Under the old system, you needed to have widespread pain, as well tenderness when pressure was applied to at least 11 out of 18 points on your body.
Over time, experts realized that many doctors didn’t know how to check for tender points or refused to do so. Plus, the older system didn’t account for many symptoms that have since been recognized as key features of fibromyalgia, like fatigue or depression.
Researchers believe the new system is better for diagnosing fibromyalgia.
Your doctor will likely use the WPI and SS to check you for signs of fibromyalgia.
They’ll use the WPI to check for a history of pain in 19 areas of your body. For each area where you’ve felt pain in the past 7 days, you’ll receive one point. Your doctor will add up all of your points for a final score between 0 and 19.
They’ll use the SS to check for symptoms in four categories unrelated to pain. This includes fatigue, cognitive problems, and other possible signs of fibromyalgia.
Your doctor will also ask you to rate the severity of these symptoms over the past week, on a scale from 0 to 3. Then they’ll add up all of your points for a final score between 0 and 12.
You might have the disorder if you receive a:
- WPI score greater than 7 and SS score greater than 5
- WPI score between 3 and 6 and SS score greater than 9
To be diagnosed with fibromyalgia, you need to have experienced symptoms at a similar level for at least 3 months. Your doctor should also take steps to rule out other possible causes of your symptoms.
The official diagnostic criteria for fibromyalgia no longer requires a tender point examination. But your doctor might still check for 18 tender points associated with the disorder. Tender points feel painful when only a small amount of pressure is applied.
To conduct a tender point exam, your doctor will press on 18 points on your body with their fingertip. They’ll use just enough pressure to whiten their nail bed. Then they’ll ask if you feel any pain.
The locations of these points include:
- between your shoulder blades
- the tops of your shoulders
- the back of your head
- the front of your neck
- your upper chest
- your outer elbows
- your upper hips
- your inner knees
- the sides of your hips
Many conditions can cause symptoms similar to those of fibromyalgia. Your doctor must rule out those conditions to make an accurate diagnosis. To do this, they may use:
- blood tests to check for signs of HIV or AIDS, hypothyroidism, rheumatoid arthritis, or Lyme disease
- X-rays, CT scans, or MRI scans to check for signs of degenerative spinal diseases or certain kinds of cancer
- tissue samples to check for cancer
They may also order other tests, like sleep studies or psychological exams.
If you suspect you may have fibromyalgia, it’s a good idea to keep a pain diary. Use it to track your daily experiences of pain, including its:
This will help your doctor get a full and accurate picture of your pain. They’ll probably use the widespread pain index and symptom severity scale to learn more about your symptoms. They may also check you for tender points.
Finally, it’s important for your doctor to rule out other possible causes of your symptoms.