Glossary of Arthritis Definitions - Rehabilitation Institute of Chicago

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Arthritis Glossary

Ankylosing spondylitis
A disease that affects the spine, causing the bones of the spine to grow together.
Aquatic Therapy
Therapy that is done in a pool, preferably in warm water, to restore movement and strength through the use of heat, buoyancy, and resistance.
Arthritis
Inflammation of a joint, usually accompanied by pain, swelling, and sometimes change in structure.
Arthroscopy
A minimally invasive diagnostic and treatment procedure used for conditions of a joint. This procedure uses a small, lighted, optic tube (arthroscope) which is inserted into the joint through a small incision in the joint. Images of the inside of the joint are projected onto a screen; used to evaluate any degenerative and/or arthritic changes in the joint; to detect bone diseases and tumors; to determine the cause of bone pain and inflammation.
Bursa
A sac filled with fluid located between a bone and a tendon or muscle.
Bursitis
Repeated small stresses and overuse that cause the bursa to swell and become irritated.
Carpal tunnel syndrome
A condition in which the median nerve is compressed as it passes through the carpal tunnel in the wrist, a narrow confined space. Since the median nerve provides sensory and motor functions to the thumb and three middle fingers, many symptoms may result.
Cartilage
A smooth material that covers bone ends of a joint to cushion the bone and allow the joint to move easily without pain.
Chiropractic
From the Greek word “chiropraktikos” meaning “effective treatment by hand.” The purpose is to locate and adjust musculoskeletal areas of the body that are functioning improperly and to restore normal function to muscles, joints, and nerves.
Computerized tomography scan (Also called a CT or CAT scan.)
A diagnostic imaging procedure that uses a combination of x-rays and computer technology to produce cross-sectional images (often called slices), both horizontally and vertically, of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat, and organs. CT scans are more detailed than general x-rays.
Electromyogram (EMG)
A test to evaluate nerve and muscle function.
Erythrocyte sedimentation rate (ESR)
A measurement of how quickly red blood cells fall to the bottom of a test tube. When swelling and inflammation are present, the blood's proteins clump together and become heavier than normal. Thus, when measured, they fall and settle faster at the bottom of the test tube. Generally, the faster the blood cells fall, the more severe the inflammation.
Fibromyalgia (Also called fibrositis.)
A chronic, widespread pain in muscles and soft tissues surrounding the joints throughout the body.
Gout
A result of a defect in body chemistry (such as uric acid in the joint fluid), this painful condition most often attacks small joints, especially the big toe. It can usually be controlled with medication and changes in diet.
Infectious arthritis
An infection in the joint fluid and tissues.
Inflammation
A normal reaction to injury or disease, which results in swelling, pain and stiffness.
Joint
Where the ends of two or more bones meet.
Juvenile rheumatoid arthritis (JRA)
A form of arthritis in children ages 16 or younger that causes inflammation and stiffness of joints for more than six weeks. Unlike adult rheumatoid arthritis, which is chronic and lasts a lifetime, children often outgrow juvenile rheumatoid arthritis. However, the disease can affect bone development in the growing child.
Lateral epicondylitis (Also known as tennis elbow.)
Pain is caused by damage to the tendons that bend the wrist backward away from the palm.
Ligaments
A white, shiny, flexible band of fibrous tissue that binds joints together and connects various bones and cartilage.
Magnetic resonance imaging (MRI)
A diagnostic procedure that uses a combination of large magnets, radiofrequencies and a computer to produce detailed images of organs and structures within the body.
Medial epicondylitis (Also known as golfer's elbow, baseball elbow, suitcase elbow, or forehand tennis elbow.)
Pain caused by damage to the tendons that bend the wrist toward the palm.
Musculoskeletal system
The complex system involving the body's muscles and skeleton and including the joints, ligaments, tendons and nerves.
Myelogram
Involves the injection of a dye or contrast material into the spinal canal; a specific x-ray study that also allows careful evaluation of the spinal canal and nerve roots.
Nodule
A bump that can appear around the joints that are affected by arthritis.
Occupational Therapist
A professional trained to help people develop skills for tasks and activities related to daily life, such as using facilities and objects around the house and the job. Occupational therapists can also provide evaluation and assistance for adaptive equipment and can help educate family members and caregivers.
Orthopaedic surgeon (Also called an orthopaedist.)
A physician who diagnoses, treats, manages the rehabilitation process and provides prevention protocols for patients who suffer from injury or disease in any of the components of the musculoskeletal system.
Orthopaedic surgery (Also called orthopaedics.)
The medical specialty devoted to the diagnosis, treatment, rehabilitation and prevention of injuries and diseases of the body's musculoskeletal system.
Osteoarthritis
A condition caused by wear and tear that causes inflammation of the joint, causing swelling, pain and stiffness.
Osteoporosis
A condition that develops when bone is no longer replaced as quickly as it is removed.
Physical Therapist
A rehabilitation clinician trained in the prevention, diagnosis and treatment of movement dysfunctions and the enhancement of a person's physical well being.
Polymyalgia Rheumatica
A rheumatic disorder that is associated with moderate to severe muscle pain and stiffness in the neck, shoulder and hip areas. It is seen almost exclusively in people over the age of 50.
Polymyositis
A rare disease that involves inflammation that results in damage to the muscle fibers.
Pseudogout
Resembles gout and, like gout, is caused by the formation of crystals in the joints, thus the name. Instead of uric acid crystals, as true gout, the pseudogout crystals are composed of a salt called calcium pyrophosphate dehydrate (CPPD).
Psoriatic arthritis
A form of arthritis associated with psoriasis, a skin and nail disease.
Raynaud’s Phenomenon
A condition in which poor blood flow results in discomfort and skin color changes in affected parts of the body. There is no cure, but it can be controlled in most cases.
Reactive arthritis (Also called Reiter's syndrome.)
A type of arthritis that occurs as a reaction to an infection.
Rheumatoid arthritis
An inflammatory disease that involves the lining of the joint (synovium). The inflammation often affects the joints of the hands and the feet and tends to occur equally on both sides of the body.
Scleroderma
A very serious disease of the body's connective tissue that causes thickening and hardening of the skin.
Soft tissues
The ligaments, tendons and muscles in the musculoskeletal system.
Spondylitis
Inflammation of the spine.
Synovial fluid
A clear, sticky fluid that is released by the synovial membrane and acts as a lubricant for joints and tendons.
Synovial membrane
A tissue that lines and seals the joint.
Systemic juvenile rheumatoid arthritis
A form of juvenile rheumatoid arthritis that affects joints and sometimes internal organs.
Systemic lupus erythematosus (lupus)
A very serious, chronic, autoimmune disorder characterized by periodic episodes of inflammation of and damage to the joints, tendons, other connective tissues and organs, including the heart, lungs, blood vessels, brain, kidneys and skin.
Tendon
The tough cords of tissue that connect muscles to bones.
Tendonitis
An inflammation in a tendon or the tendon covering.
x-ray
A diagnostic test which uses invisible electromagnetic energy beams to produce images of internal tissues, bones and organs onto film.