Abduction: Movement of a limb away from the midline of the body.
Acetabulum: The cup portion of the hip socket that sits in the pelvis.
Acetaminophen: A commonly used analgesic medication containing no aspirin.
Acupressure: Eastern medicine practice of applying pressure to certain sites called meridians, as opposed to inserting needles.
Acupuncture: Ancient Chinese practice of inserting needles into specific points of the body for the purpose of healing and relieving pain.
Acute: A disease or condition characterized by sudden onset and limited to short duration.
Adduction: Movement of a limb toward the midline of the body.
Adrenal gland: Small gland located at the top of the kidney producing hormones that regulate many body functions.
Aerobic exercise: Vigorous exercise promoting the circulation of oxygen through the blood.
Analgesic: A medication with pain-relieving properties.
Antibody: An immunoglobulin or immune protein produced by white blood cells. Antibody production is triggered by the presence of an antigen.
Antigen: A substance the body perceives as foreign that stimulates production of antibodies.
Antinuclear antibodies: Antibodies directed against structures inside the nucleus of cells. The presence of antinuclear antibodies serves as markers for some rheumatic diseases.
Arthritis: Inflammation of a joint.
Arthrocentesis: A sterile procedure using a needle to obtain joint fluid.
Arthrodesis: Surgical fusion of a joint.
Arthroplasty: A surgical procedure to replace a joint with an artificial joint.
Arthroscopy: A surgical technique using a thin tube-like instrument inserted into a joint to view and repair damage.
Aspiration: See Arthrocentesis.
Autoantibody: Antibody against the body's own tissues.
Autoimmune disease: A disease in which the immune system of the body turns on itself, targeting its own tissues, joints, and organs.
Bacteria: Single-cell microorganisms causing infection.
B-cell: White blood cells that produce antibodies (immunoglobulins).
Biofeedback: A treatment approach that measures physiological responses and trains the patient to control the responses. Used to relieve stress and various painful conditions.
Biologic-response modifier: A substance used to stimulate or restore the ability of the immune system to fight disease.
Biologic therapy: Treatments employing biologic-response modifiers.
Bursa: A fluid-filled sac between tendon and bone or tendon and skin.
Capsaicin: Found in topical creams, a chemical derived from peppers that has painkilling properties.
Carpal tunnel: A tunnel in the underside of the wrist formed by bone and the transverse ligament that houses the median nerve.
Cartilage: Tissue covering the ends of the bones in a joint, acting as a cushion.
Chiropractor: A practitioner of chiropractic.
Clinical-research trial: Human trials designed to evaluate the efficacy and safety of medications and medical devices yet to be approved.
Combination therapy: When two or more medications are used in combination to treat a disease, as opposed to a single medication.
Comorbid condition: Medical conditions occurring together.
Complement: A complex system of proteins found in blood plasma that combine with antibodies to destroy foreign matter.
Connective tissue: A type of tissue that supports and connects body structures.
Corticosteroid: Steroid hormone made by the cortex of the adrenal gland.
Costochondritis: Inflammation of the cartilage of the chest wall, cartilage of the sternum, and possibly cartilage of a rib. Pain mimics cardiac chest pain.
COX-2 inhibitor: A drug that blocks the actions of COX-2 enzymes.
C-Reactive Protein (CRP): An indicator of the presence and intensity of inflammation, not associated with a specific condition.
Crepitus: A clinical symptom characterized by a peculiar crackling, crinkly, or grating feeling or sound under the skin, lungs, or in the joints.
Cyclooxygenase-1 (COX-1): An enzyme important in the production of prostaglandins. Functions include protecting the stomach and maintaining blood flow to kidneys.
Cyclooxygenase-2 (COX-2): An enzyme that speeds up production of pros-taglandins.
Plays a role in swelling and pain associated with arthritis.
Cytokine: A protein produced by white blood cells, acting as a chemical messenger between cells, either to stimulate or inhibit cellular activity.
Cytoplasm: The substance of a cell outside of the nucleus.
Degenerative joint disease: Synonymous with osteoarthritis.
DMARDs: Disease-modifying antirheumatic drugs; used to slow progression of rheumatoid arthritis or other forms of inflammatory arthritis.
DNA: Deoxyribonucleic acid; the basis for encoding genetic information.
Double-blinded study: Neither the study participants nor the researchers know who in the test groups got the medication with the active ingredients.
Efficacy: Effectiveness of a drug or treatment.
Effusion: An abnormal accumulation of fluid.
Embryonic stem cells: Stems cells derived from the inner mass of cells of a young embryo.
Enbrel: The first anti-TNF alpha drug approved for the treatment of rheumatoid arthritis in 1998.
Endorphins: Natural painkillers produced by the nervous system.
Enzyme: A protein that catalyzes or speeds up chemical reactions in living organisms.
Erosion: Holes in bone or cartilage from chronic inflammation.
Erythema: Redness of skin due to inflammation or drug reactions.
Erythrocyte sedimentation rate (ESR): A laboratory test using a special tube to test the rate of falling red blood cells over a period of time. A high ESR is an indicator of inflammation.
Fatigue: Lack of energy, tired, physically drained.
FDA: The United States Food and Drug Administration; the federal agency that regulates food, drugs, and medical devices.
Flexibility exercise: Exercises to prevent stiffness, such as muscle stretches.
Folic acid: B vitamin prescribed for people who also take methotrexate, since methotrexate depletes folic acid.
Gait: The way you walk. Stride.
Gene: A sequence of chromosomal DNA.
Gene therapy: Treatment of disease by replacing, altering, or supplementing a gene that is abnormal and causing disease.
Glucosamine: A component of cartilage.
Health assessment questionnaire (HAQ): Clinical assessment of quality of life for people living with rheumatoid arthritis. Also assesses difficulty with everyday tasks.
Heberden's node: Calcified spur of the DIP joint of the finger seen with osteoarthritis.
Herbal remedy: Medications derived from plants.
Heredity: Genetic transmission from parent to child.
Human leukocyte antigen (HLA): The histocompatibility system can also serve as genetic markers for rheumatic diseases.
Humira: The third anti-TNF alpha drug approved for the treatment of rheumatoid arthritis. A fully human monoclonal antibody.
Hyaluronan: Substance used for viscosupplementation injections.
Hydrotherapy: Synonymous with water therapy or water exercise. The warmth and buoyancy of the water helps people with arthritis exercise.
Hyperuricemia: Abnormally elevated level of uric acid in the blood.
Immune: Protected against infection or foreign substances by antibodies.
Immune response: Activation of the immune system against foreign substances (i.e., antigens).
Immune system: A complex system that detects anything foreign to the body, and the organs and cells protecting the body from foreign substances and infection.
Immunocompromised: Immune system impaired by disease.
Immunoglobulins: Proteins that are antibodies.
Immunosuppressive agent: Medication that halts immune system activity.
Infection: The invasion and multiplication of bacteria, viruses, and parasites in the body.
Inflammation: Localized redness, swelling, pain, and warmth due to infection or injury.
Interleukin: Proteins that communicate between white blood cells.
Intravenous: Into a vein. Given through a vein.
Isometric exercise: Exercises that tighten muscle without moving joints.
Isotonic exercise: Exercises that strengthen muscle by moving joints.
Joint: The area where the ends of two bones come together, facilitating movement.
Joint aspiration: See Arthrocentesis.
Joint replacement surgery: Also known as arthroplasty. Replacing a joint with an artificial one.
Leukocyte: A white blood cell.
Ligament: A band of connective tissue connecting two bones.
Lymphocytes: A type of white blood cell, including T and B cells.
Lymphoma: A tumor of lymphoid tissue.
Macrophage: A type of white blood cell that ingests foreign substances.
Median: In the middle. The median nerve runs through the middle of the wrist.
Methotrexate: A DMARD used to treat rheumatoid arthritis and some other rheumatic diseases.
Mixed connective tissue disease (MCTD): A combination of systemic lupus erythematosus, scleroderma, and polymyositis.
Monoclonal antibody: Antibodies produced in a laboratory that bind to specific cells. Made from a single clone of cells.
Monotherapy: Use of a single treatment or medication.
Morning stiffness: Characteristic of having rheumatoid arthritis; patients wake very stiff in their joints and it can take more than an hour to be relieved.
MRI: Magnetic resonance imaging.
Musculoskeletal: Of the skeletal system, including muscles, bones, tendons, ligaments, and cartilage.
Myalgia: Muscle pain.
Myositis: Inflammation of muscle tissue.
Narcotic: Drugs that block pain by blocking signals from the central nervous system to the brain.
National Institutes of Health (NIH): An agency in the United States devoted to medical research. Consists of twenty-four individual institutes.
Nephritis: Inflammation of the kidney.
Nerve: A fiber bundle using electrical and chemical signals to transmit sensory and motor information throughout the body.
NIAMS: The National Institute of Arthritis and Musculoskeletal and Skin Diseases; a part of the NIH.
Nodule: A collection of tissue that can be felt and can exist at any level of skin.
NSAIDs: Nonsteroidal anti-inflammatory drugs; used to treat inflammation.
Nucleus: The structure of the cell containing the chromosomes.
Obese: People who are more than 20 percent over their ideal weight.
Occupational therapist: A trained and licensed therapist who teaches patients how to relearn skills required for daily living tasks.
Opiate: A medication derived from the opium poppy acting as narcotic sedatives, suppressing the central nervous system.
Opioids: Synthetic narcotics that resemble natural opiates.
Orthovisc: A substance used for viscosupplementation injections.
Osteophytes: Bone spurs.
Osteoporosis: Bone-thinning disease resulting in abnormally low bone mass.
Osteotomy: Cutting into or through a bone to remove a part.
Palindromic rheumatism: A type of joint inflammation where the affected joint changes periodically from one part of the body to another and back again.
Paraffin wax: Hands are dipped into warm, melted paraffin wax to relieve pain and stiffness.
Parathyroid gland: The gland that regulates calcium metabolism.
Pauciarticular: Affects four or fewer joints.
Peripheral neuropathy: Abnormal functioning of the nerves outside the spinal cord.
Pheresis: Procedure where blood is filtered, separated, and a portion is returned to the patient.
Photosensitivity: A medication side effect of conditions like lupus. Sensitivity of the skin to light.
Placebo: A sugar pill or pill with no active ingredients, used in clinical trials as a control for comparative purposes.
Placebo effect: The person receiving an inactive ingredient reports a decrease in symptoms.
Plasma: The liquid portion of blood, without the red and white blood cells.
Podagra: Gout in the big toe.
Polyarthritis: Arthritis in many joints.
Polyarticular: Involvement of many joints.
Polymyalgia rheumatica: A condition affecting muscles and joints, characterized by pain and stiffness on both sides of the body, involving shoulders, arms, neck, and buttocks.
Polymyositis: An inflammatory disease of the muscle.
Pronation: Rotation of the arm or leg inward.
Prosorba: Antibodies are removed from blood of a rheumatoid arthritis patient using a special filtering machine.
Prostaglandin: A hormone-like substance that modulates inflammation as well as having other functions.
Prosthesis: An artificial replacement for a joint or other body part.
Purines: Proteins found in most foods and in all human tissues.
Quality of life: A patient's ability to lead and enjoy a normal life and normal activities.
Radiograph: An x-ray.
Randomized: Determined by chance, as in a clinical trial.
Range of motion: The full normal movement potential for a joint.
Refractory: Resistant to treatment.
Regimen: A planned course of action.
Remicade: The second anti-TNF alpha drug approved for the treatment of rheumatoid arthritis. Administered by infusion.
Remission: A period when symptoms subside.
Repetitive-stress injury: An injury that develops following overuse of a joint or muscle.
Research, controlled: A clinical trial comparing a treated group of study participants to a control group.
Restless leg syndrome: Uncomfortable sensations in the legs while sitting or lying still, resulting in a painful condition.
Revision: A surgery required to revise a previous joint replacement because of failure of the prosthesis.
Rheumatic disease: Conditions characterized by pain and stiffness of joints and muscles.
Rheumatism: An older term referring to painful conditions of muscles, bones, joints, and tendons.
Rheumatoid arthritis: An inflammatory type of arthritis that is also classified as an autoimmune disease. The pattern of joints affected is usually symmetric.
Rheumatoid factor: An antibody measurable in the blood. It is detectable in 80 percent of rheumatoid arthritis patients and used to help diagnose the condition.
Rheumatoid nodule: Lumps of skin, usually around pressure points, common to rheumatoid arthritis patients.
Rheumatologist: A medical doctor specializing in the diagnosis and treatment of arthritis and other related conditions.
Rheumatologist, pediatric: A rheumatologist who specializes in treating children with arthritic conditions.
Rheumatology: A specialty of internal medicine focusing on rheumatic diseases and conditions.
Salicylates: A subgroup of NSAIDs that does include aspirin.
Scleritis: Inflammation of the sclera (the white outer coat of the eyeball).
Sclerodactyly: Localized thickening of the skin of the fingers and toes.
Sclerosis: Localized hardening of the skin.
Sedimentation rate: See Erythrocyte sedimentation rate.
Seronegative rheumatoid arthritis: Rheumatoid arthritis patients who are negative for rheumatoid factor. About 20 percent of people with rheumatoid arthritis are seronegative.
Side effect: Undesirable consequences of treatment.
Soft-tissue rheumatism: Rheumatic conditions affecting the soft tissues of the body (bursitis, tendonitis).
Spirochete: A bacterial organism with a spiral shape.
Spondylitis: Inflammation of one or more vertebrates.
Spontaneous remission: A disappearance of symptoms, usually rare and early in the disease.
Stem cell: A cell which has the ability to grow into any of the body's cell types, of which there are more than 200. Stem cells are unspecialized cells.
Steroid: Potent drugs used to relieve swelling and inflammation, such as prednisone and cortisone.
Subcutaneous: Under the skin, as in an injection given under the skin.
Supination: Rotation of the arm or leg outward.
Supplement: Dietary supplements include vitamins, minerals, herbals, botanicals, amino acids, and enzymes.
Symmetric arthritis: Arthritis affecting same joints on both sides of the body.
Symptom: Subjective evidence of a disease or medical condition.
Syndrome: A combination of signs and symptoms that together present a disease state.
Synovectomy: Surgical removal of the synovium (lining of the joint).
Synovial fluid: The slippery fluid that lubricates the joints.
Synovial lining: The lining of the joints responsible for producing joint fluid.
Synovitis: Inflammation of the synovial lining of the joints.
Synvisc: One of the hyaluronates used for viscosupplementation injections.
Systemic disease: Throughout the body, meaning organs as well as joints.
T cell: A type of white blood cell made in the bone marrow, which migrates to the thymus gland, where it matures and differentiates into other types of T cells and plays a role in the immune system.
Temporomandibular Joint Syndrome (TMJ): Causes pain in the jaw and in front of the ear.
Tendon: Connects muscle to bone.
Therapeutic: Of or relating to treatment.
Therapy: Treatment of disease.
THR: Total hip replacement.
Tick bite: Bite from a bloodsucking parasitic insect; method of transmission for Lyme disease.
Tissue: A layer of cells that have certain functions.
TKR: Total knee replacement.
Tophi: The plural of tophus, indicative of more than one.
Tophus: A nodule comprised of uric acid crystals.
Topical creams: Applied to the surface of the skin.
Tumor necrosis factor-alpha (TNF-alpha): An inflammatory cytokine.
Ulcer: Erosion of skin or of the mucous membrane.
Ulnar deviation: Hand deformity associated with rheumatoid arthritis. The fingers drift in the opposite direction of the thumb or away from the thumb.
Uric acid: A substance resulting from protein metabolism.
Uveitis: Inflammation of the inner eye.
Vasculitis: A group of diseases that cause inflammation of the blood vessels.
Viscosupplementation: Injection of gel-like substances into a joint to supplement the viscous properties of synovial fluid.
Yoga: Through movements and deep breathing, yoga brings together mind, body, and spirit.