Joint pain and muscle aches are common symptoms that can be caused by a variety of conditions. Two of the most common are arthritis and fibromyalgia. While there is some overlap in symptoms, there are key differences between these two chronic pain conditions.
What is Arthritis?
Arthritis refers to joint inflammation and consists of over 100 different types that can affect people of all ages. The two most common types are:
- Osteoarthritis – Wear-and-tear arthritis that occurs with aging. It affects joints like knees, hips, hands, and spine.
- Rheumatoid arthritis – An autoimmune disease where the immune system attacks joint linings, causing inflammation. It often starts in smaller joints like hands and feet.
In both types of arthritis, joint inflammation leads to pain, stiffness, swelling, and decreased range of motion. Symptoms tend to be worse in the morning and after periods of inactivity.
What Causes Arthritis?
The exact cause depends on the type:
- Osteoarthritis occurs from years of wear-and-tear on joints through everyday use or injury/trauma to joints.
- Rheumatoid arthritis is caused by the immune system attacking healthy tissue in the joints.
- Other types can be caused by uric acid crystal buildup (gout) or by infections.
Genetics and lifestyle factors like obesity and repetitive joint use increase arthritis risk. Osteoarthritis risk also rises with age as cartilage breaks down over time.
Who Gets Arthritis?
According to the Arthritis Foundation:
- Osteoarthritis affects over 32.5 million adults in the US.
- Rheumatoid arthritis affects over 1.5 million adults in the US.
- Arthritis is more common in women than men.
- Risk increases with age – over 50% of adults 65+ have some type of arthritis.
What is Fibromyalgia?
Fibromyalgia is a chronic condition causing widespread pain, fatigue, sleep issues, and cognitive difficulties. It affects the central nervous system,leading to hypersensitivity to pain.
Fibromyalgia pain often occurs without inflammation or damage to joints or muscles. Instead, it is believed to arise from the brain and nerves misinterpreting normal sensory signals from the body as painful.
What Causes Fibromyalgia?
The exact cause of fibromyalgia is still unknown. Leading theories include:
- Abnormalities in pain processing pathways in the brain
- Sleep disturbances reducing pain thresholds
- Changes in neurotransmitter function
- Trauma, illness, or stress triggering onset
- Genetic predisposition
While the triggers are unclear, fibromyalgia appears to involve miscommunication between the nervous system and brain leading to increased sensitivity to normal pain signals.
Who Gets Fibromyalgia?
According to the CDC:
- 2-6% of the global population has fibromyalgia – around 10 million in the US.
- Between 75-90% of fibromyalgia patients are women.
- Onset is most common between ages 30-50.
- It often runs in families.
Differences Between Arthritis and Fibromyalgia
While arthritis and fibromyalgia share some general symptoms like pain and fatigue, there are key differences:
Pain Location
- Arthritis: Pain is located in joints affected by inflammation or damage. Common sites are knees, hips, hands, feet, and spine.
- Fibromyalgia: Pain is widespread and felt all over the body – both above and below the waist, on both sides, and along the spine.
Pain Type
- Arthritis: Joint pain that worsens with movement and improves with rest.
- Fibromyalgia: Constant dull ache with heightened responses to pressure that does not improve with rest.
Joint Changes
- Arthritis: Physical joint damage can be seen on x-rays or clinical exam – joint swelling, redness, deformity.
- Fibromyalgia: No inflammation or damage in the joints evident on exams or imaging.
Sleep Disturbance
- Arthritis: Pain can interrupt sleep but does not usually cause insomnia by itself.
- Fibromyalgia: Nonrestorative sleep and insomnia are hallmark symptoms.
Triggers
- Arthritis: Joint overuse, injury, aging, genetics, and autoimmune issues are common triggers.
- Fibromyalgia: Stress, trauma, illness, and mood disorders like anxiety and depression can trigger onset.
Gender Distribution
- Arthritis: Slightly more common in women.
- Fibromyalgia: Up to 90% of patients are women.
Age of Onset
- Arthritis: Onset increases with age, most common after age 45.
- Fibromyalgia: Can occur at any age but peaks between 30-50 years old.
Overlap Between Arthritis and Fibromyalgia
While they have distinct features, arthritis and fibromyalgia can co-occur:
- 20-30% of people with fibromyalgia also have rheumatoid arthritis or osteoarthritis.
- Joint pain from arthritis can trigger fibromyalgia flares.
- People with autoimmune arthritis appear more prone to developing fibromyalgia.
- Both conditions share risk factors like female gender, family history, and mood disorders.
Having both conditions together typically leads to more widespread pain, fatigue, disability, and lower quality of life compared to having only one condition.
Arthritis and Fibromyalgia Diagnosis
Since the diseases share some symptoms, testing is needed to distinguish between them:
Arthritis Diagnosis
- Physical exam checking for joint swelling, redness, warmth, deformities.
- Imaging tests like x-rays, MRI to visualize joint damage.
- Blood tests looking for inflammatory markers or autoantibodies.
- Joint fluid analysis checking for inflammation.
Fibromyalgia Diagnosis
- Physical exam checking for tender points throughout the body.
- Ruling out other conditions like thyroid disorders, rheumatoid arthritis.
- History of widespread pain for over 3 months.
- No evidence of joint swelling or damage on exam or imaging.
There are no blood tests to diagnose fibromyalgia. Diagnosis is based on clinical criteria after excluding other potential causes.
Treating Arthritis vs. Fibromyalgia
Management approaches differ based on the condition:
Arthritis Treatment
- Medications – Non-steroidal anti-inflammatories (NSAIDs), steroids, disease-modifying antirheumatic drugs (DMARDs).
- Surgery – Joint repair or replacement for severe osteoarthritis.
- Lifestyle approaches – Exercise, physical therapy, weight loss, joint protection.
Goals are decreasing inflammation, slowing disease progression, and preserving joint mobility and function.
Fibromyalgia Treatment
- Medications – Antidepressants, anti-seizure drugs, pain relievers.
- Lifestyle approaches – Low impact aerobic exercise, cognitive behavioral therapy (CBT), stress reduction.
- Alternative therapies – Acupuncture, massage, heat/cold therapy.
Goals are reducing widespread pain, regulating sleep, and improving daily function and quality of life.
Can You Have Both Arthritis and Fibromyalgia?
It is definitely possible to have both rheumatoid or osteoarthritis along with fibromyalgia. Some features that may point to having both include:
- You have tender, inflamed joints typical of arthritis.
- You also have widespread muscle pain and achiness above and below the waist.
- Joint pain is localized to affected joints but you have generalized body aches.
- You have exhaustion, nonrestorative sleep, and cognitive issues along with joint pain.
- Arthritis medications help your joint pain but not the overall body aches.
If you have both localized joint symptoms plus diffuse pain and fatigue, be sure to get evaluated for both arthritis and fibromyalgia. Treating both conditions together gives the best chance at relief.
The Bottom Line
While arthritis and fibromyalgia share some common symptoms, they are distinct conditions:
- Arthritis involves joint inflammation and damage leading to pain and stiffness. It shows physical exam and imaging findings.
- Fibromyalgia stems from nerve hypersensitivity causing body-wide pain without joint damage. There are no positive physical findings.
People can have either condition alone or they can co-occur in the same person. Diagnosis is made based on clinical evaluation and characteristic symptoms and pattern of pain. Being aware of overlapping as well as unique features helps distinguish between arthritis and fibromyalgia to guide appropriate treatment.