Causes for inflammation in joints and muscular pain

by Nathan Wei, MD, FACP, FACR

Nathan Wei is a nationally known board-certified rheumatologist and author of the Second Opinion Arthritis Treatment Kit. It's available exclusively at this website... not available in stores.

Click here: Second Opinion Arthritis Treatment Kit



Inflammation is a condition where the body's immune system, which consists largely of special white blood cells and chemicals messengers, protects a person from infection and foreign invaders such as bacteria and viruses.

In some diseases, unfortunately, the immune system triggers an inflammatory response when there are no foreign substances to fight off. In these conditions, called autoimmune diseases, the body's normally protective immune system damages its own tissues. The body responds as if normal tissues are infected or somehow abnormal. This process is termed “autoinflammation.”

Many types of joint and muscle disease are the result of “autoinflammation.” Arthritis is a general term that describes inflammation in joints. Some types of arthritis associated with inflammation include:

• Rheumatoid arthritis
• Psoriatic arthritis
• Gout
• Pseudogout
• Reiter’s disease
• Polymyalgia rheumatica


Other painful conditions of the joints and musculoskeletal system that are generally not considered inflammatory include fibromyalgia and muscle strain. Previously, it was felt that osteoarthritis was not inflammatory; however, that theory has changed.

Inflammation is characterized by:

• Swelling
• Redness
• Heat
• Joint pain

Further symptoms of inflammation include:

• Joint stiffness
• Loss of joint function


Inflammation may also be associated with constitutional symptoms including:

• Fever
• Chills
• Fatigue
• Malaise (loss of energy)
• Headaches
• Loss of appetite
• Muscle stiffness


When inflammation occurs, chemicals from the body's white blood cells- these are called “cytokines”- are released into the blood or affected tissues to protect the host from foreign invaders. This release of chemicals increases the blood flow to the area of injury or infection and results in redness and warmth. Some of the chemicals cause a leak of fluid into the tissues, resulting in swelling. This protective process may stimulate nerves and cause pain.

The increased number of cells and inflammatory substances within the joint causes more inflammation to occur leading to wearing down of cartilage (cushions at the end of bones) and swelling of the joint lining.

Inflammatory diseases are diagnosed with:

• Medical history and physical exam
• Specific diagnostic tests


Inflammation can affect organs. The type of symptoms depend on which organs are affected. For example:

• Inflammation of the heart (myocarditis) may cause shortness of breath or fluid retention (eg., lupus, virus infection)
• Inflammation of the small tubes that transport air to the lungs may cause an asthma attack
• Inflammation of the kidneys (nephritis) may cause high blood pressure or kidney failure (lupus, Wegener’s disease)
• Inflammation of the large intestine (colitis) may cause cramps and diarrhea (Crohn’s)


Pain may not be a primary symptom of systemic inflammatory disease, since many organs do not have many pain-sensitive nerves. Treatment of organ inflammation is directed at the cause of inflammation.

There are a number of treatment options for inflammatory joint diseases including medications, rest and exercise, and surgery to correct joint damage. The type of treatment prescribed will depend on several factors including the type of disease, the person's age, type of medications he or she is taking, overall health, medical history and severity of symptoms.

The goals of treatment are to:

• Avoid or modify activities that aggravate pain
• Relieve pain through analgesics (pain-relieving medications) and anti-inflammatory medications
• Maintain joint movement and muscle strength through physical therapy
• Decrease stress on the joints by using assistive devices such as braces, splints or canes as needed


There are many medications available to decrease joint pain, swelling and inflammation and hopefully prevent or minimize the progression of the inflammatory disease. The medications include:

• Non-steroidal anti-inflammatory drugs (NSAIDs - such as aspirin, ibuprofen or naproxen)
• Corticosteroids (such as prednisone)
• Anti-malarial medications (such as hydroxychloroquine)
• Disease-modifying anti-rheumatic drugs (DMARDS) such as methotrexate, azathioprine, sulfasalazine, cyclophosphamide, cyclosporine
• Biologic Response Modifiers (BRMS) such as etanercept, adalimumab, infliximab, anakinra


Muscle aches and pains are common and can involve more than one muscle. Muscle pain also can involve ligaments, tendons, and fascia, the soft tissues that connect muscles, bones, and organs together.

Muscle pain is most frequently related to tension, overuse, or muscle injury from exercise or physically-demanding work. In these situations, the pain tends to involve specific muscles and starts during or just after the activity. It is usually obvious which activity is causing the pain.

Muscle pain also can be a sign of conditions affecting the whole body, like some infections (including the flu) and disorders that affect connective tissues throughout the body (such as lupus).

One common cause of muscle aches and pain is fibromyalgia, a condition that includes tenderness in the muscles and surrounding soft tissue, sleep difficulties, fatigue, and headaches.

The most common causes are:

• Tension or stress
• Overuse: using a muscle too much, too soon, too often
• Injury or trauma including sprains and strains

Muscle pain may also be due to:

• Polymyositis
• Dermatomyositis
• Lupus
• Fibromyalgia
• Polymyalgia rheumatica
• Infections, including:
o An abscess in the muscle
o Trichinosis (roundworm)
o Influenza (the flu)
o Lyme disease
o Malaria
o Rocky Mountain spotted fever
o Polio
o Many others
• Electrolyte imbalances like too little potassium or calcium
• Rhabdomyolysis
• Drugs, including:
o Cocaine
o Statins for lowering cholesterol (such as atorvastatin, simvastatin, and lovastatin)
o ACE inhibitors for lowering blood pressure (such as enalapril and captopril)
o Many others

For muscle pain from overuse or injury, rest that body part and take acetaminophen or ibuprofen. Apply ice for the first 24 - 72 hours of an injury to reduce pain and inflammation. After that, heat often feels more soothing.

Muscle aches from overuse and fibromyalgia often respond well to massage. Gentle stretching exercises after a long rest period are also helpful.

Regular exercise can help restore proper muscle tone. Walking, cycling, and swimming are good aerobic activities to try. A physical therapist can teach the patient stretching, toning, and aerobic exercises to feel better and stay pain-free. Begin slowly and increase workouts gradually. Avoid high-impact aerobic activities and weight lifting when injured or while in pain.

Be sure to get plenty of sleep and try to reduce stress. Yoga and meditation are excellent ways to help with sleep and relaxation.

If these measures aren't working, call the doctor, who will consider prescription medication, physical therapy referral, or referral to a specialized pain clinic.

If muscle aches are due to a specific disease, follow the instructions of the doctor to treat the primary illness.

Call the doctor if:

• muscle pain persists beyond 3 days
• there is severe, unexplained pain
• there is any sign of infection, like swelling or redness around the tender muscle
• there is poor circulation in the area where the muscles aches You have a tick bite or a rash
• the muscle pain has been associated with starting or changing doses of a medicine, such as a statin (atorvastatin, simvastatin, or lovastatin)


The doctor will perform a physical examination and ask questions about muscle pain, such as:

• When did it start? How long did it last?
• Where is it exactly? Is it all over or only in a specific area?
• Is it always in the same location?
• What makes it better or worse?
• Do other symptoms occur at the same time, like joint pain, fever, vomiting, weakness, malaise, or difficulty using the affected muscle?
• Is there a pattern to the occurrences?
• Have there been any new medications lately?


Diagnostic tests that may be performed include:

• Blood tests to look at CBC, muscle enzymes (creatine kinase), and possibly a test for Lyme disease or a connective tissue disorder


Physical therapy may be helpful.

Prevention

• Warm up before exercising and cool down afterward.
• Stretch before and after exercising.
• Drink lots of fluids before, during, and after exercise.
• Stretch at least every hour while at work.

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