Osteoarthritis, the most common form of arthritis, is a type of arthritis that occurs when flexible tissue at the end of bones gradually wears down. People with osteoarthritis can experience joint pain anywhere, but most commonly it is pain in the hands, neck, lower back, knees, or hips. Osteoarthritis is often referred to as a wear and tear disease that is more common with older age.

Rheumatoid arthritis (RA) is an autoimmune and inflammatory disease, causing a person’s immune system to attack healthy cells in the body by mistake. This causes inflammation and painful swelling in the affected parts of the body. RA most commonly affects joints in the hands, wrists, and knees. The specific causes of RA are unknown, but risk factors can include age, sex, genetics, smoking, and obesity. Treatment for RA usually includes the use of medications that slow disease and prevent joint deformity.

Radicular pain, often called sciatica when affecting a lower extremity nerve, refers to pain that radiates along the path of a nerve. Typically, radicular pain affects only one side of the body. It can occur when a herniated disk, bone spur on the spine or narrowing of the spine compresses a spinal nerve. This causes inflammation, pain and, sometimes, numbness and weakness in the affected leg.

Back pain most commonly occurs in the lower back, or lumbar region. Low back pain can be related to an injury, spinal condition, or muscle strain. There are several risk factors for low back pain, and certain behaviors can cause or worsen the pain, including:

• Habituation and guarding
• Stress
• Age
• Muscle strain
• Smoking
• Excess weight

Tension-type are the most common type of headache. They range in severity from mild to severe, and pain can be experienced in different parts of the head, face, and neck. Certain activities can trigger tension-type headaches, such as:

• Stress
• Insomnia
• Eye strain
• Head and neck pain caused by other conditions

A migraine is a headache that can cause severe throbbing pain or a pulsing sensation, usually on one side of the head. It’s often accompanied by nausea, vomiting, and extreme sensitivity to light and sound.

Endometriosis is a chronic pain condition in which tissue similar to the tissue that normally lines the uterus, the endometrium, grows outside your uterus. This abnormal tissue thickens, breaks down and bleeds with each menstrual cycle. Because this tissue has no way to exit your body, it becomes trapped. People with endometriosis generally describe the pain as severe pain, especially during menstrual periods.

Pelvic inflammatory disease (PID) is an infection of the female reproductive organs including the uterus, fallopian tubes, or ovaries. PID can be a complication when sexually transmitted diseases (STDs) go untreated. Symptoms of PID include pain in the lower abdomen, fever, and a burning sensation when urinating. If PID is not diagnosed and treated early, it can cause scar tissue, infertility, and long-term pelvic pain.

Interstitial Cystitis is a condition that impacts the bladder and can cause bladder pressure, bladder pain, and sometimes pelvic pain. With interstitial cystitis, pelvic nerves in the bladder do not function properly, causing changes to sensation and urination. This condition mostly affects women but can also be present in men.

Peripheral Neuropathy is a chronic condition that is a result of damage to the nerves located outside of the brain and spinal cord (peripheral nerves), often causing weakness, numbness and pain, usually in the hands and feet. It can also affect other areas and body functions including digestion, urination and circulation. People with peripheral neuropathy generally describe the pain as stabbing, burning or tingling.

Multiple sclerosis (MS) is a chronic condition of the brain and spinal cord (central nervous system). MS causes the immune system to attack the protective casing (myelin) that covers nerve fibers, and causes communication problems between the brain and the rest of the body. Eventually, the disease can cause permanent damage or deterioration of the nerves. People with MS generally describe the pain as numbness or weakness in one or more limbs or electric-shock sensations that occur with certain neck movements.

Cancer refers to a large number of chronic conditions that are characterized by the development of abnormal cells that divide uncontrollably and have the ability to destroy normal body tissue. Signs and symptoms caused by cancer will vary depending on what part of the body is affected. This type of pain is sometimes treated differently and more aggressively than other chronic pain conditions.

Fibromyalgia is a disorder characterized by widespread musculoskeletal pain accompanied by fatigue, sleep, memory and mood issues. Researchers believe that fibromyalgia amplifies painful sensations by affecting the way your brain and spinal cord process sensory signals. People with Fibromyalgia generally describe the pain as a constant dull ache that has lasted for at least three months.

Inflammatory Bowel Disease (IBD) is an umbrella term used to describe disorders that involve chronic inflammation of the digestive tract. The most common types of IBD include Ulcerative Colitis and Crohn’s disease. People with IBD can experience diarrhea, rectal bleeding, abdominal pain, fatigue and weight loss.

Sickle cell anemia is an inherited red blood cell disorder in which there aren’t enough healthy red blood cells to carry oxygen throughout the body. Periodic episodes of severe pain, called sickle crises, are a major symptom of sickle cell anemia. Pain develops when abnormally shaped red blood cells block blood flow through tiny blood vessels to the chest, abdomen and joints.

Complex regional pain syndrome (CRPS) is a rare form of chronic pain that usually affects an arm or a leg. CRPS typically develops after an injury, a surgery, a stroke or a heart attack, but can also occur without a clear precipitating event. The pain is out of proportion to any tissue injury and it can involve changes to blood flow, skin color, strength and tissue growth. People with CRPS generally describe the pain as burning or throbbing pain, usually in an arm, leg, hand or foot.