Causes
Bone pain is usually deep, penetrating, or dull. It commonly results from injury. Other less common causes of bone pain include bone infection (osteomyelitis), hormone disorders, and tumors.
Muscle pain(known as myalgia) is often less intense than bone pain but can be very unpleasant. For example, a muscle spasm or cramp (a sustained painful muscle contraction) in the calf is an intense pain that is commonly called a charley horse. Pain can occur when a muscle is affected by an injury, loss of blood flow to the muscle, infection, or a tumor.
Tendon and ligament painis often less intense than bone pain. It is often described as "sharp" and is worse when the affected tendon or ligament is stretched or moved and is usually relieved by rest. Common causes of tendon pain include tendinitis, tenosynovitis, lateral epicondylitis or medial epicondylitis, and tendon injuries. The most common cause of ligament pain is injury (sprains).
Bursae paincan be caused by trauma, overuse, gout, or infection. Bursae are small fluid-filled sacs that provide a protective cushion around joints. Usually, pain is worse with movement involving the bursa and is relieved by rest. The affected bursa may swell.
Joint pain(called arthralgia) may or may not be related to joint inflammation (called arthritis). Arthritis may cause swelling as well as pain. A wide variety of disorders can cause arthritis, including inflammatory arthritis (such as rheumatoid arthritis), osteoarthritis, infectious arthritis, gout and related disorders, autoimmune disorders (such as systemic lupus erythematosus) and vasculitic disorders (such as immunoglobulin A–associated vasculitis), osteonecrosis, and injuries affecting the part of a bone inside a joint. Arthritic pain can be new (acute, for example, when caused by infections, injuries, or gout), or longstanding (chronic, for example, when caused by rheumatoid arthritis or osteoarthritis). Pain resulting from arthritis is typically worse when the joint is moved but usually is present even when the joint is not being moved. Sometimes pain originating in structures near the joint, such as ligaments, tendons, and bursae, seems to be coming from the joint.
Testing
Blood tests are useful only in supporting the diagnosis made by the doctor after an examination. A diagnosis is not made or confirmed by a blood test alone. Examples of such blood tests include rheumatoid factor and antinuclear antibodies, which are used to help diagnose common causes of arthritis, such as rheumatoid arthritis and systemic lupus erythematosus. Usually, such tests are recommended only if symptoms specifically suggest such a disorder.
X-rays are primarily used to take images of bones, but they do not show muscles, tendons, and ligaments. X-rays are usually taken if the doctor suspects a fracture or, less commonly, a bone tumor or infection or to look for changes that confirm a person has a certain kind of arthritis (for example, rheumatoid arthritis or osteoarthritis).
Magnetic resonance imaging (MRI) unlike plain x-rays, can identify abnormalities of soft tissues, such as muscles, bursae, ligaments, and tendons. Thus, MRI may be used when the doctor suspects damage to a major ligament or tendon or damage to important structures inside a joint; it may not be better than a standard x-ray in the evaluation of many painful conditions. MRI can detect fractures that are not visible on x-rays.
Computed tomography (CT) is more sensitive than an x-ray and is often used to obtain more detail about a fracture or bone problem that was found with plain x-rays. A CT scan is useful if MRI cannot be done or is unavailable.
Other imaging tests include ultrasonography, arthrography (an x-ray procedure in which a radiopaque dye is injected into a joint space to outline the structures, such as ligaments inside the joint), and bone scanning. These tests may help doctors diagnose certain conditions. Doctors may remove a sample of bone, the lining of the joint (synovium), or other tissues for examination under a microscope (biopsy).
Treatment
Pain relievers
Other measures to relieve pain
Pain is usually best relieved by treating its cause. The doctor may recommend pain relievers such as acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs), or if the pain is severe, opioids. Depending on the cause, applying cold or heat or immobilizing the joint may help relieve musculoskeletal pain.