What is Arthritis?

The more than 150 forms of arthritis involve not only joints and bones, but also entire organ systems in some cases. Effects of these many forms of arthritis range from fleeting to chronic and from mildly painful to debilitating, even life threatening.

Information about these many conditions is available from many sources in many forms. Following are very basic, brief definitions of each form of arthritis, collected and in some cases adapted from multiple sources, as well as links to several central and local resources.

http://www.arthritis.org/resources/gettingstarted/forms.asp http://www.arthritis.com/ http://arthritis-research.com/ http://www.niams.nih.gov/
http://www.cdc.gov/nccdphp/arthritis/ http://www.medicinenet.com/arthritis/article.htm

Achilles tendonitis

Achilles tendonitis is the inflammation of the large tendon at the back of the ankle, which connects the large calf muscles to the heel bone.

Achondroplasia

Achondroplasia is a condition in which abnormal bone growth results in short stature with unusually short arms and legs, a large head, and compacted facial features.

Acromegalic arthropathy

Acromegaly is the thickening of cartilage related to excess growth hormone activity. This thickened cartilage tends to wear earlier and faster than normal, which leads to arthropathy.

Adhesive capsulitis

Commonly known as “frozen shoulder,” adhesive capsulitis is the formation of excess fibrous tissue in the shoulder joint capsule that causes pain and reduced range of motion.

Adult Onset Still's disease

Still's disease is a form of arthritis that is characterized by high spiking fevers and evanescent (transient) salmon-colored rash. Still's disease was first described in children, but it is now known to occur, much less commonly, in adults (in whom it is referred to as adult-onset Still's disease).

Ankylosing spondylitis

Ankylosing Spondylitis (ANK-ki-low-sing spon-di-LIE-tis) is a chronic, or long-lasting, disease that primarily affects the spine and may lead to stiffness of the back. The joints and ligaments that normally permit the back to move become inflamed. The joints and bones may grow (fuse) together.

Anserine bursitis

Pain and tenderness on the inside of your knee, just about two inches below the joint, are two of the symptoms of pes anserine bursitis of the knee. The pes anserine bursa is a small lubricating sac located between the shinbone (tibia) and three tendons of the hamstrings muscle at the inside of the knee. Because the three tendons splay out on the front of the shinbone and look like the foot of a goose, pes anserine bursitis is also known as "goose foot" bursitis.

Avascular necrosis

Osteonecrosis (OS-tee-oh-knee-CROW-sis), also called Avascular Necrosis (A-vas-cue-lar-knee-CROW-sis), is a bone disorder that decreases the blood supply to the affected area, leads to tiny breaks within the bone, and can eventually cause bones to collapse.

Behcet's syndrome

Behçet's Disease (beh-CHETTS) disease is a rare and chronic condition that affects the inner lining of the mouth and genitals and the small blood vessels throughout the body. Symptoms of Behcet's disease include recurrent ulcers in the mouth (resembling canker sores) and on the genitals, and eye inflammation. The disorder may also cause various types of skin lesions, arthritis, bowel inflammation, meningitis (inflammation of the membranes of the brain and spinal cord), and cranial nerve palsies. Behcet's is a multi-system disease; it may involve all organs and affect the central nervous system, causing memory loss and impaired speech, balance, and movement. Behçet's Disease usually affects more women than men in the U.S. and primarily young adults in their 20s and 30s.

Bicipital tendinitis

Bicipital Tendonitis is an inflammation of a shoulder tendon and is a common cause of pain due to its position and function.

Blount's disease

Blount's disease is a growth disorder of the shinbone that causes the lower leg to angle inward.

Brucellar spondylitis

Brucellosis is a common disease in animals which is transmittable to humans and is particularly common in the Mediterranean countries. Brucella organisms may localize in almost any organ. Spondylitis is considered one of the most serious refractory complications.

Bursitis

Bursitis, tendinitis, and other soft tissue diseases such as myofascial syndrome, are rheumatic diseases that affect the tissues and structures that surround a joint and produce pain, swelling or inflammation. Bursitis is inflammation of the bursa, the small fluid-filled sac that acts like a cushion between muscles and tendons, or between muscles and bones.

Calcaneal bursitis

Calcaneal bursitis is inflammation of the sac connecting the Achilles tendon to the heel.

Calcium pyrophosphate dihydrate (CPPD)

Calcium Pyrophosphate Dihydrate Crystal Deposition (CAL-see-um PIE-row-FOX-fate DIE-high-drate DEH-poo-ZISH-un) is a build up of crystals in the joints where they damage cartilage and cause pain, redness, heat, and swelling. Also referred to as Pseudo Gout or Chondrocalcinosis

Crystal deposition disease

Crystal deposition disease is another common term for the condition caused by calcium pyrophosphate dehydrate deposits.

Caplan's syndrome

Caplan's syndrome is inflammation and scarring of the lungs in people with rheumatoid arthritis who have exposure to coal dust.

Carpal tunnel syndrome

Carpal tunnel syndrome is a painful progressive condition caused by compression of a key nerve in the wrist. It occurs when the nerve that runs from the forearm into the hand becomes pressed or squeezed at the wrist.

Chondrocalcinosis

Chondrocalcinosis is the calcification of cartilage resulting from the build up of crystals in the joint.

Chondromalacia patellae

Chondromalacia (pronounced KON-DRO-MAH-LAY-SHE-AH), also called chondromalacia patellae, refers to softening of cartilage of the kneecap. The cartilage softens when, instead of gliding smoothly across the lower end of the thigh bone, the kneecap rubs against it.

Chronic synovitis

Chronic synovitis is a general term for diseases involving joint inflammation in children.

Chronic recurrent multifocal osteomyelitis

Chronic recurrent multifocal osteomyelitis (CRMO) is a rare disease of children involving swelling of various bony sites, especially bones of the arms and legs and the collar bone. Bacterial cultures of affected tissue report negative in nearly all cases.

Churg-Strauss syndrome

Also known as Allergic granulomatosis, Churg-Strauss Syndrome (CSS) is a swelling of the blood vessels in various organ systems. The condition is often accompanied by a high white blood cell count and fever.

Cogan's syndrome

A condition causing swelling of the cornea and cranial nerves, resulting in blurred vision, eye pain, sensitivity to light, nausea, dizziness, ringing of the ears and deafness.

Corticosteroid-induced osteoporosis

Osteoporosis is a disease that makes bones more porous and easier to break than normal bone. The production of strong healthy bone is dependent on a balance between bone growth and bone break down. Using steroids can decrease the formation of new bone, increase the breakdown of old bone, and decrease the absorption of calcium from the intestine.

Costosternal syndrome

Otherwise known as costochondritis, costosternal syndrome is a painful inflammation of the cartilage connecting the ribs to the sternum.

CREST syndrome

CREST is a form of Systemic Sclerosis (scleroderma or hardening) which is characterized by Calcinosis (calcium deposits), usually in the fingers; Raynaud's syndrome (sudden constriction of the blood vessels in the fingers);loss of muscle control of the Esophagus, which can cause difficulty swallowing; Sclerodactyly, a tapering deformity of the bones of the fingers; and Telangiectasia, small red spots on the skin of the fingers, face, or inside of the mouth.

Cryoglobulinemia

Cryoglobulinemia is the presence of cryoglobulins in the blood, abnormal forms of protein molecules that precipitate at cold temperatures and redissolve at normal body temperature. Hence, when a person with cryoglobulinemia is exposed to cold, he or she may experience impaired circulation in the small blood vessels. This may lead to color changes in the skin, hives, damage to the extremities, bleeding into the skin (purpura), and other problems.

Degenerative joint disease

A slowly progressive musculoskeletal disorder that typically affects the joints of the hand (especially those involved with a pinch grip), spine and weight-bearing joints (hips, knees) of the lower extremity. It is not associated with systemic symptoms or joint inflammation. Joint pain and loss of function are due to defects in joint cartilage and underlying bone. These defects arise because of excessive loads on normal joints or normal loads on abnormal joints. It is sometimes called erosive inflammatory osteoarthritis.

Dermatomyositis

Dermatomyositis is one of a group of acquired muscle diseases called inflammatory myopathies. The disease, which has a somewhat severe onset, affects both children and adults. Females are more often affected than males. Dermatomyositis is characterized by a rash accompanying, or more often, preceding muscle weakness. The rash looks like patchy, bluish-purple discolorations on the face, neck, shoulders, upper chest, elbows, knees, knuckles, and back. Some people may also develop calcium deposits, which appear as hard bumps under the skin.

Diabetic finger sclerosis

Otherwise known as digital sclerosis, this condition involves a thickening and hardening of the skin on the fingers (or toes), which in turn causes stiffness.

Diffuse idiopathic skeletal hyperostosis (DISH)

DISH (sometimes called Forestier’s disease) is considered a form of degenerative arthritis and is characterized by excessive bone growth along the sides of the vertebrae of the spine. It is also associated with inflammation and calcification (bone growth) at other areas of the body where tendons and ligaments attach to bone, such as at the elbow, knee and the heel of the foot. These can lead to bone spurs. Heel spurs, for example, are common among people with DISH.

Discitis

Discitis is inflammation of an intervertebral disc due to infection.

Discoid lupus erythematosus

Discoid lupus erythematosus is a chronic skin condition characterized by inflammation and scarring type skin lesions which occur on the face, ears, scalp and at times on other body areas. These lesions develop as an inflamed growth with scaling and a warty like appearance. The center areas may appear lighter in color surrounded by an area darker than the normal skin. When lesions occur in hairy areas such as the scalp, permanent scarring and hair loss can occur. A small percentage of patients with discoid lupus can develop disease of the internal organs which can make the person sick.

Drug-induced lupus

Lupus-inducing drugs are typically those used to treat chronic diseases. No obvious common denominator links the drugs that are likely to cause lupus. The list includes medicines used to treat heart disease, thyroid disease, hypertension, neuropsychiatric disorders, certain anti-inflammatory agents and antibiotics.

Duchenne's muscular dystrophy

Duchenne muscular dystrophy (DMD) is one of a group of muscular dystrophies characterized by the enlargement of muscles. DMD is one of the most prevalent types of muscular dystrophy and is characterized by rapid progression of muscle degeneration that occurs early in life.

Dupuytren's contracture

Dupuytren's contracture is an abnormal thickening of tough tissue in the palm and fingers that can cause the fingers to curl. It is more common in men than in women and becomes more common as we grow older.

Ehlers-Danlos syndrome

Ehlers-Danlos Syndrome (A-lerz-DAN-los SIN-drome) describes a group of hereditary disorders which mainly affect the skin and joints, but may affect other organs. EDS affects the connective tissues -- the tissues that support various parts of the body such as skin, muscles, tendons and ligaments. In EDS, the fibrous protein collagen is faulty, causing the connective tissue to not be elastic or strong.

Enteropathic arthritis

Enteropathic arthritis involves the peripheral joints, usually in the lower extremities such as the knees or ankles. It commonly involves only a few or a limited number of joints and may closely follow the bowel condition. This occurs in approximately 11 percent of patients with ulcerative colitis and 21 percent of those with Crohn's disease. The synovitis is generally self-limited and non-deforming.

Epicondylitis

Commonly known either as tennis or golf elbow depending upon the orientation of symptoms, is inflammation or degeneration of the tendon that attaches to the bony bit (lateral or medial epicondyle) on the outside or inside of the arm or elbow.

Erosive inflammatory osteoarthritis

A slowly progressive musculoskeletal disorder that typically affects the joints of the hand (especially those involved with a pinch grip), spine and weight-bearing joints (hips, knees) of the lower extremity. It is not associated with systemic symptoms or joint inflammation. Joint pain and loss of function are due to defects in articular cartilage and underlying bone. These defects arise because of excessive loads on normal joints or normal loads on abnormal joints. It is sometimes called degenerative joint disease (DJD).

Exercise-induced compartment syndrome

Exercise induced compartment syndrome, also called exertional compartment syndrome and chronic compartment syndrome, is a condition that causes pain over the front of the shin bone. Patients typically experience the pain after a period of activity or exercise, and it is quickly relieved by rest. The pain from exercise induced compartment syndrome can be quite severe, and it often limits a patient's activity level.

Fabry's disease

Fabry's disease is a fat storage disorder caused by a deficiency of an enzyme involved in the biodegradation of lipids. There is some evidence of a link between Fabry’s disease and connective disorders including osteoarthritis.

Familial Mediterranean fever

Familial Mediterranean fever (FMF), usually characterized by recurrent episodes of fever and peritonitis (inflammation of the abdominal membrane), occurs most commonly in people of non-Ashkenazi Jewish, Armenian, Arab, and Turkish background.

Farber's lipogranulomatosis

Farber's Disease is a rare inherited metabolic disorder. Major symptoms may include hoarseness, painful and swollen joints, nodules under the skin, and growths in the lungs and other parts of the body. The heart and lymph nodes may also be involved. Difficulty in breathing may necessitate the implantation of a breathing tube (tracheotomy) in the throat.

Felty's syndrome

A typical form of rheumatoid arthritis with fever, splenomegaly and leukopenia and, in some cases, anaemia and thrombocytopenia. Other features can include anorexia, weight loss, recurrent infections, brown pigmentation of exposed skin surfaces, peripheral neuropathy, carpal tunnel syndrome, arteritis, general malaise, pain in the upper left quadrant of the abdomen, Raynaud's syndrome and scleritis. Occurs most often in patients with a sustained period of illness, more often in women than in men. Still disease or syndrome, also called Still-Chauffard-Felty syndrome, is a juvenile form.

Fibromyalgia

FMS (fibromyalgia syndrome) is a widespread musculoskeletal pain and fatigue disorder for which the cause is still unknown. Fibromyalgia means pain in the muscles, ligaments, and tendons – the soft fibrous tissues in the body.

Fifth's disease

Fifth’s disease is a viral illness in children that is among the most common causes of arthritis in children. Known as "post-viral arthritis," painful swelling develops in one or more joints one to two weeks after a child has contracted Fifth’s disease or various other common viral ailments. The arthritis may last for a few days or even several weeks but passes without any permanent damage. Any virus can lead to an arthritis, but the most common causes are Parvovirus, the agent of Fifth's Disease, and Epstein Barr Virus, the agent of infectious mononucleosis.

Flat feet

Feet with lower arches and higher than normal degree of flexibility in the arch can lead to biomechanical wear and tear on various joints including toes, heels, knees and even the hips and back.

Foreign body synovitis

Foreign body synovitis is a painful swelling of joint tissues because of irritation from a “foreign body” such as a thorn or other sharp object.

Freiberg's disease

Freiberg’s disease involves enlargement of the head of a bone in the foot. The enlargement results from regeneration after and injury and blood loss to the bone during formative years.

Fungal arthritis

Fungal arthritis usually results from the spread of an invasive fungal infection from another organ in the body, more often in patients who are especially vulnerable to infection. The fungal infection creates swelling when it reaches the joint or bone tissue. Load bearing joints, particularly the knees, are the more common locations.

Gaucher's disease

Gaucher disease is an inherited metabolic disorder in which harmful quantities of a fatty substance called glucocerebroside accumulate in the spleen, liver, lungs, bone marrow, and sometimes in the brain. The disease can lead to bone pain and loss of blood to the bone, creating arthritic symptoms, most often in the hips, shoulders and spine.

Giant cell arteritis

Giant cell arteritis, also known as temporal arteritis and cranial arteritis, involves swelling of arteries in the head (most often the temporal arteries, which are located on the temples on each side of the head), neck, and arms. This swelling causes the arteries to narrow, reducing blood flow. Though it has not been determined why, the condition is often present in people also experiencing polymyalgia rheumatica.

Gonococcal arthritis

Gonoccal arthritis is an infection of one or more joints that occurs in people who have been infected with gonorrhea.

Goodpasture's syndrome

Goodpasture's syndrome is a disease in which the immune system makes antibodies that attack the lungs and kidneys.

Gout

Gout (gowt) causes sudden, severe attacks of pain and tenderness, redness, warmth, and swelling in some joints. Usually affects one joint at a time -- often the big toe.

Granulomatous arteritis

Another name for giant cell arteritis.

Hemarthrosis

Hemarthrosis results from bleeding in the joints, either from injury or hemophilia or both. Presence of blood in the joint leads to inflammation and can lead to erosion of bone.

Hemochromatosis

Hemochromatosis, the most common form of iron overload disease, is an inherited disorder that causes the body to absorb and store too much iron. Arthritis is one among many conditions resulting from such iron build-up.

Henoch-Schonlein purpura

Also known as Anaphylactoid purpura or Vascular purpura, Henoch-Schonlein is a swelling of blood vessels caused by an abnormal response of the immune system. The exact cause for this disorder is unknown. Symptoms include purple spots on the skin, joint pain, gastrointestinal symptoms, and glomerulonephritis (a type of kidney disorder).

Hip dysplasia

Hip dysplasia is a general term used to describe a group of hip problems, often related to loose connective tissues and positions that stress the area (for example, baby swaddling). While the problems may not be symptomatic in early stages, they can result in arthritis later in life.

Hurler syndrome

Hurler syndrome is an inherited disease that belongs to a group of diseases called mucopolysaccharidoses. Storage of abnormal quantities of this material (mucopolysaccharide) in different body tissues is responsible for the symptoms and appearance of the disease.

Hypermobility syndrome

The joint hypermobility syndrome is a condition that features joints that easily move beyond the normal range expected for a particular joint. Joint hypermobility can also be related to a rare, but more significant medical condition called Ehlers-Danlos syndrome that is characterized by weakness of the connective tissues of the body.

Hypersensitivity vasculitis

Leukocytoclastic vasculitis (LCV) is a term commonly used to describe swelling of the small blood vessels. Many possible causes exist for this condition, but a cause is not found in as many as 50% of patients. The problem may be localized to the skin, or it may occur in other organs. The internal organs most commonly affected include the gastrointestinal tract or the kidneys. Joints are also commonly affected.

Hypertrophic osteoarthropathy

Hypertrophic osteoarthropathy (HOA) is a clinical syndrome of clubbing of the fingers and toes, enlargement of the extremities, and painful swollen joints. The condition causes pain in the fibrous tissue that wraps the bones of the legs and feet.

Immune complex disease

Immune complexes are clusters of interlocking antigens and antibodies. Under normal conditions immune complexes are rapidly removed from the bloodstream by the spleen and liver. In some circumstances, however, immune complexes continue to circulate. Eventually they become trapped in the tissues of the kidneys, lung, skin, joints, or blood vessels. There they set off reactions that lead to inflammation and tissue damage.

Impingement syndrome

Impingement syndrome is a condition that affects the rotator cuff, causing shoulder pain. The rotator cuff is a group of muscles and tendons that secures the arm to the shoulder joint and allows the arm to rotate.

Jaccoud's arthropathy

Named after French physician Sigismond Jaccoud, Jacoud’s arthropathy is joint disease that occurs after rheumatic fever, often in the hands and feet. The same type of reversible joint deformities can occur after the onset of several other rheumatic conditions including rheumatoid arthritis and lupus.

Juvenile ankylosing spondylitis

Juvenile ankylosing spondylitis (JAS) is a type of arthritis that affects the spine and the sites where the muscles, tendons, and ligaments are attached to bone. "Ankylosing" means stiff or rigid, "spondyl" means spine, and "itis" refers to inflammation. The disease causes inflammation of the spine and large joints, resulting in stiffness and pain. The disease may result in erosion at the joint between the spine and the hip bone (the sacroiliac joint), and the formation of bony bridges between vertebrae in the spine, fusing those bones. In addition, bones in the chest may fuse.

Juvenile dermatomyositis

Juvenile dermatomyositis is thought to be an autoimmune disease in which the immune system fights infections or injuries through inflammation (IN fluh MAY shun), or swelling. The first sign of JM is usually a skin rash. JM patients can have weak muscles at the same time they see the skin rash, or the weak muscles may come after the rash over days, weeks or months. The weaker muscles are usually closer to the body (for example, neck, shoulders, back, and stomach), and you may notice your child having trouble climbing or standing from a seated position. The skin rash and weak muscles are caused by inflammation or swelling in the blood vessels under the skin and in the muscles, also called vasculitis (vas kyoo LIE tis).

Juvenile rheumatoid arthritis

Juvenile rheumatoid arthritis is arthritis that causes joint inflammation and stiffness for more than 6 weeks in a child of 16 years of age or less. Inflammation causes redness, swelling, warmth, and soreness in the joints, although many children with JRA do not complain of joint pain. Any joint can be affected and inflammation may limit the mobility of affected joints. One type of JRA can also affect the internal organs. Doctors classify JRA into three types by the number of joints involved, the symptoms, and the presence or absence of certain antibodies found by a blood test.

Kawasaki disease

Also known as mucocutaneous lymph node syndrome because it affects the mucous membranes (the lining of the mouth and breathing passages), the skin, and the lymph nodes (part of the immune system), Kawasaki disease can also lead to vasculitis, which is an inflammation of the blood vessels. This can affect all major arteries in the body - especially the coronary arteries, which supply blood to the heart. It can also cause inflammation of the heart muscle, a condition called myocarditis. However, the degree to which the heart and blood vessels are involved varies from child to child.

Kienbock's disease

Kienbock's Disease is deterioration of a bone in the wrist (the lunate bone) from loss of blood supply.

Legg-Calve-Perthes disease

Legg-Calvé-Perthes disease (LCPD) is the name given to unexplained bone damage in the thigh from loss of blood supply to the bone. The goal of treatment is to avoid severe degenerative arthritis.

Lesch-Nyhan syndrome

Lesch-Nyhan syndrome (LNS) is a rare, inherited disorder caused by a deficiency of the enzyme hypoxanthine-guanine phosphoribosyltransferase (HPRT). The lack of HPRT causes a build-up of uric acid in all body fluids, and leads to symptoms such as severe gout, poor muscle control, and moderate retardation, which appear in the first year of life. Abnormally high uric acid levels can cause sodium urate crystals to form in the joints, kidneys, central nervous system, and other tissues of the body, leading to gout-like swelling in the joints and severe kidney problems.

Linear scleroderma

Linear Scleroderma is a line of thickened skin which can affect the bones and muscles underneath it, thus limiting the motion of the affected joints and muscles. It most often occurs in the arms, legs, or forehead, and may occur in more than one area.

Lipoid dermatoarthritis

Multicentric reticulohistiocytosis (MRH) is a rare disease in which skin lesions are associated with arthritis that involves the finger and toe joints and becomes severe enough to cause extensive destruction of the joints (known as arthritis mutilans). The disease can involve the bones, the tendons, the muscles, the joints, and nearly any other organ (eg, eyes, larynx, thyroid, salivary glands, bone marrow, heart, lung, kidney, liver, gastrointestinal tract) and can sometimes be associated with cancer.

Lofgren's syndrome

Lofgren's syndrome is the association of swollen lymph tissue and small, painful red nodules under the skin and joint pain. It is commonly found in women of Irish, Puerto Rican, and Swedish heritage. It occurs in only about 10 to 15% of patients with sarcoidosis. Patients usually have a good response to corticosteroids as well as good prognosis.

Lyme disease

Lyme disease is a bacterial illness caused by a bacterium called a "spirochete." The actual name of the bacterium is Borrelia burgdorferi. Lyme disease is spread by ticks when they bite the skin permitting the bacterium to infect the body. Lyme disease can cause abnormalities in the skin, joints, heart and nervous system. When joints are affected, arthritis, or inflammation in the joints, begins with swelling, stiffness, and pain. Usually, only one or a few joints become affected, most commonly the knees. The arthritis of Lyme disease can look like many other types of arthritis and can become chronic.

Malignant synovioma

A cancerous tumor that develops in tendon and joint tissues, usually in the legs, malignant synovioma can also occur in the abdominal wall and other trunk muscles.

Marfan's syndrome

The Marfan syndrome is a heritable condition that affects the connective tissue. The primary purpose of connective tissue is to hold the body together and provide a framework for growth and development. In the Marfan syndrome, the connective tissue is defective and does not act as it should. Because connective tissue is found throughout the body, the Marfan syndrome can affect many body systems, including the skeleton, eyes, heart and blood vessels, nervous system, skin and lungs.

Medial plica syndrome

Plica syndrome of the knee is a constellation of signs and symptoms that occur secondary to injury or overuse. An otherwise normal structure, a plica can be a significant source of pain in the back of the knee. Once swelling sets in, the normal plical tissue may enlarge and become problematic.

Metastatic carcinomatous arthritis

Arthritis is sometimes, though rarely, caused by cancerous tissues in and about joints.

Mixed connective tissue disease (MCTD)

Mixed connective tissue disease (MTCD) describes what may be an overlapping group of connective tissue disorders that cannot be diagnosed in more specific terms. These disorders include systemic lupus erythematosus, polymyositis, and scleroderma. Individuals with MCTD have symptoms of each of these disorders including arthritic, cardiac, pulmonary and skin manifestations; kidney disease; muscle weakness; and dysfunction of the esophagus. The exact cause of mixed connective tissue disease is unknown.

Mixed cryoglobulinemia

Mixed cryoglobulinemia (MC) is a chronic autoimmune disorder (when the body’s defenses turn on itself) that is almost always associated with chronic liver inflammation due to hepatitis C virus (HCV) infection. It is believed to develop when chronic liver inflammation causes B cells to grow out of control and produce excessive amounts of antibodies, especially anti-IgG antibodies known as rheumatoid factors.

Mucopolysaccharidosis

The mucopolysaccharidoses (MPSs) are a group of inherited lysosomal storage disorders, meaning conditions in which cells cannot adequately digest and eliminate waste. MPSs are caused by a deficiency of specific lysosomal enzymes required for the degradation of glycosaminoglycans (GAGs) (mucopolysaccharides).

Multicentric reticulohistiocytosis

Multicentric reticulohistiocytosis is a rare systemic disease in cells designed to digest and eliminate waste grow out of control and attack joint and skin tissues.

Multiple epiphyseal dysplasia

Multiple epiphyseal dysplasia (MED) is a rare inherited spectrum of disorders characterized by malformation (dysplasia) of the "growing portion" or head of the long bones (epiphyses). Affected individuals may have an abnormally short thighbone (femur), unusually short hands and fingers, mild short stature, a waddling gait, and/or pain in the hips and knees. In some cases, painful swelling and inflammation of certain joints (arthritis) may be present as early as five years of age.

Mycoplasmal arthritis

Mycoplasmal arthritis is inflammation of joint and bone tissues due to infection by a mycoplasmal microorganisms.

Myofascial pain syndrome

Myofascial Pain Syndrome (MPS) is a painful musculoskeletal condition, a common cause of musculoskeletal pain. MPS is characterized by the development of Myofascial trigger points (TrPs) that are locally tender when active, and refer pain through specific patterns to other areas of the body. A trigger point or sensitive, painful area in the muscle or the junction of the muscle and fascia (hence, myofascial pain) develops due to any number of causes. Trigger points are usually associated with a taut band, a ropey thickening of the muscle tissue. Typically a trigger point, when pressed upon, will cause the pain to be felt elsewhere. This is what is considered "referred pain".

Neonatal lupus

Neonatal lupus is a rare autoimmune disorder that is present at birth (congenital). Affected infants often develop a characteristic red rash or skin eruption. In addition, infants with neonatal lupus may develop liver disease, a heart condition known as congenital heart block, and/or low numbers of circulating blood platelets that assist in blood clotting functions (thrombocytopenia). The symptoms associated with neonatal lupus, with the exception of congenital heart block, usually resolve within the first several months of life.

Neuropathic arthropathy

Neuropathic osteoarthropathy can be defined as bone and joint changes (damage, deformity, debris in the joints) that occur secondary to loss of sensation and that accompany a variety of disorders.

Nodular panniculitis

Weber-Christian disease is a skin condition that features recurring inflammation in the fat layer of the skin. The lesions are symmetric in distribution, and the thighs and lower legs are affected most frequently. Fatigue, fever, and joint pain frequently occur. Nausea, vomiting, abdominal pain, weight loss, and liver enlargement may also occur. Because its cause is unknown, Weber-Christian disease is often referred to as idiopathic lobular or nodular panniculitis.

Ochronosis

A condition often associated with alkaptonuria and marked by pigment deposits in cartilages, ligaments, and tendons.

Olecranon bursitis

Olecranon bursitis causes fluid to collect in a sac that lies behind the elbow, called the olecranon bursa. A bursa is a slippery, sac-like tissue that normally allows smooth movement around bony prominences, such as the point behind the elbow. When a bursa becomes inflamed for some reason, the sac fills with inflammatory fluid. This can cause pain and a noticeable swelling behind the elbow.

Osgood-Schlatter's disease

Osgood-Schlatter's disease usually occurs in teenagers. It causes pain and swelling just below the knee. It is named after the two people who first described it. It is not serious and usually goes away in time. Overuse of the quadriceps muscle can cause repeated stress and strain on the attachment of the patella ligament to the growing tibia. This can cause inflammation and pain at the site of the ligament attachment. In some cases, a small flake of bone is pulled off the tibia by the pulling ligament. Healing bone (callus) then forms which may cause a hard bony bump to develop. Osteoarthritis

Osteoarthritis

Osteoarthritis (AH-stee-oh-ar-THREYE-tis) is the most common type of arthritis, especially among older people. Sometimes it is called degenerative joint disease or osteoarthrosis. Osteoarthritis is a joint disease that mostly affects the cartilage (KAR-til-uj). Cartilage is the slippery tissue that covers the ends of bones in a joint. Healthy cartilage allows bones to glide over one another. It also absorbs energy from the shock of physical movement. In osteoarthritis, the surface layer of cartilage breaks down and wears away. This allows bones under the cartilage to rub together, causing pain, swelling, and loss of motion of the joint. Over time, the joint may lose its normal shape. Also, bone spurs--small growths called osteophytes--may grow on the edges of the joint. Bits of bone or cartilage can break off and float inside the joint space. This causes more pain and damage.

People with osteoarthritis usually have joint pain and limited movement. Unlike some other forms of arthritis, osteoarthritis affects only joints and not internal organs. For example, rheumatoid arthritis--the second most common form of arthritis--affects other parts of the body besides the joints. It begins at a younger age than osteoarthritis, causes swelling and redness in joints, and may make people feel sick, tired, and (uncommonly) feverish.

Osteochondromatosis

Synovial osteochondromatosis (SOC), also called synovial chondromatosis, is a non-cancerous condition in which the synovial lining of a joint, bursa, or tendon sheath grows excessively, and fragments may break off from the synovial surface into the joint. In this location and nourished by synovial fluid, the fragments may grow, calcify, or ossify.

Osteogenesis imperfecta

Osteogenesis imperfecta (OI) is a genetic disorder characterized by bones that break easily, often from little or no apparent cause. There are at least four recognized forms of the disorder, representing a range of severities. For example, a person may have just a few or as many as several hundred fractures in a lifetime. Signs of the disease can include bones that break easily, loose joints and muscle weakness, a bluish tint to the whites of the eyes, a triangular face, a tendency toward spinal curvature and brittle teeth. Symptoms of the mildest forms of this condition can be confused with evidence of child abuse.

Osteomalacia

Osteomalacia involves softening of the bones caused by a deficiency of vitamin D or problems with the metabolism of this vitamin.

Osteomyelitis

Osteomyelitis (pronounced: os-tee-oh-my-uh-lie-tus) is a bone infection that is often caused by a bacteria called Staphylococcus aureus (pronounced: sta-fuh-low-kah-kus are-ee-us). Depending on how the bone becomes infected and the age of the person, other types of bacteria can cause it, too. In kids and teens, osteomyelitis usually affects the long bones of the arms and legs.

Osteonecrosis

Also called avascular necrosis, a condition in which part of the bone is no longer alive and cannot regenerate itself due to a lack of blood supply, sometimes following a traumatic injury to the bone. The juvenile version of osteonecrosis is known as PerthesDisease and usually afflicts children from ages four through twelve.

Osteoporosis

Osteoporosis is a disease in which bones become fragile and more likely to break. If not prevented or if left untreated, osteoporosis can progress painlessly until a bone breaks. These broken bones, also known as fractures, occur typically in the hip, spine, and wrist.

Overlap syndrome

Overlap syndrome is the term used to describe when Systemic Sclerosis (thickening or hardening of tissues) appears in conjunction with features of one or more other connective tissue diseases (such as Systemic Lupus Erythematosus, Polymyositis, Dermatomyositis).

Pachydermoperiostosis

Pachydermoperiostosis is a rare inherited condition that typically appears during childhood or adolescence and progresses slowly for about ten years. Symptoms of Pachydermoperiostosis may be enlargement of the fingers and toes (clubbing), a condition in which there is a fibrous covering on the ends of the long bones (periostosis), coarse facial features, increased bulk of the skin on the scalp forming folds, depressions or furrows (cutis verticis gyrata), and/or excessive sweating of the hands and feet.

Paget's disease of bone

Paget’s disease is a chronic disorder that can result in enlarged and misshapen bones. The excessive breakdown and formation of bone tissue causes affected bone to weaken – resulting in bone pain, misshapen bones, fractures, and arthritis in the joints near the affected bones. Paget’s disease typically is localized, affecting just one or a few bones, as opposed to osteoporosis, for example, which affects all the bones in the body. Scientists do not know for sure what causes Paget’s disease. In some cases, the disease runs in families, and so far two genes have been identified that predispose affected people to develop Paget’s disease. In most cases, however, scientists suspect that environmental factors play a role. For example, scientists are studying the possibility that a slow-acting virus may cause Paget’s disease.

Palindromic rheumatism

Palindromic rheumatism is a rare type of inflammatory arthritis. It's characterized by recurrent attacks of painful swelling of the joints and surrounding tissues.

The attacks usually affect only one or two joints at a time. They start abruptly and can last for hours or days. The attacks may recur with unpredictable frequency — from every few days to every few months. Although palindromic rheumatism can recur over many years, it doesn't usually cause permanent joint damage.

Palindromic rheumatism typically affects people between the ages of 20 and 50. No single test can confirm a diagnosis. A doctor may make a diagnosis based on medical history and signs and symptoms.

Patellofemoral pain syndrome

Patellofemoral pain is a common knee problem. If you have this condition, you feel pain under and around your kneecap. The pain can get worse when you're active or when you sit for a long time. You can have the pain in only one knee, or you can have pain in both knees.

The exact cause of patellofemoral pain isn't known. It probably has to do with the way your kneecap (patella) moves on the groove of your thigh bone (femur).

Pellegrini-Stieda syndrome

Pellegrini-Stieda syndrome is a hardening of a the top part of one of the ligaments in the middle of the knee, sometimes occurring as a complication of athletic injuries. Clinically there is swelling, pain, and limitation of motion of the joints with tenderness where the thigh bone connects to the knee.

Pigmented villonodular synovitis

Pigmented villonodular synovitis (called PVNS for short) is a joint problem that usually affects the hip or knee. It can also occur in the shoulder, ankle, elbow, hand or foot. When you have PVNS, the lining of a joint becomes swollen and grows. This growth harms the bone around the joint. The lining also makes extra fluid that can cause swelling and make the joint hurt. Piriformis syndrome

The piriformis syndrome is a condition in which the piriformis muscle (the muscle we use to rotate our thigh) irritates the sciatic nerve, causing pain in the buttocks and referring pain along the course of the sciatic nerve. This referred pain, called "sciatica", often goes down the back of the thigh and/or into the lower back. Patients generally complain of pain deep in the buttocks, which is made worse by sitting, climbing stairs, or performing squats.

Plantar fasciitis

Plantar fasciitis, which may cause the heel to hurt, feel hot or swell, is inflammation of the plantar fascia, a thin layer of tough tissue supporting the arch of the foot. Repeated microscopic tears of the plantar fascia cause pain. Sometimes plantar fasciitis is called "heel spurs", but this is not always accurate, since bony growths on the heel may or may not be a factor.

Polyarteritis nodosa

Polyarteritis nodosa (PAN) is an inflammation throughout an entire arterial wall. It is sometimes also called “systemic necrotizing vasculitis”, but this term is non-specific as other forms of vasculitis also have systemic and necrotizing features.

Polymyalgia rheumatica

Polymyalgia rheumatica is a rheumatic disorder that is associated with moderate to severe muscle pain and stiffness in the neck, shoulder, and hip area. Stiffness is most noticeable in the morning. This disorder may develop rapidly--in some patients, overnight. In other people, polymyalgia rheumatica develops more gradually.

Polymyositis

Polymyositis is a disease of muscle featuring inflammation of the muscle fibers. The cause of the disease is not known. It begins when white blood cells, the immune cells of inflammation, spontaneously invade muscles. The muscles affected are mostly those closest to the trunk or torso. This results in weakness which can be severe. It is a chronic illness with periods of increased symptoms, called flares or relapses, and decreased symptoms, known as remissions.

Polymyositis can be associated with skin rash and is then referred to as "dermatomyositis." It also can affect other areas of the body and is, therefore, a systemic illness. Occasionally, it is associated with cancer, or with other diseases of connective tissue (see systemic lupus erythematosus, scleroderma and rheumatoid arthritis).

Popliteal cysts

Popliteal or Baker's cyst is a fluid collection behind the knee. This cyst may be formed by the connection of a normal bursa (a normal lubricating fluid sac) with the knee joint. This type is more common in children. The condition can also be caused by the herniation of the knee joint capsule out into the back of the knee, which is more common in adults. This type of Baker's cyst is commonly associated with a tear in the meniscal cartilage of the knee. In older adults, this condition is frequently associated with degenerative arthritis of the knee.

Posterior tibial tendinitis

Posterior tibial tendonitis is an uncommon problem of the foot. When this tendon is inflamed in posterior tibial tendonitis or if the posterior tibial tendon ruptures, it can cause serious problems. Most commonly, patients with posterior tibial tendonitis complain of pain in the inside of the foot and ankle, and occasionally have problems associated with an unstable gait.

Pott's disease

Tuberculosis (TB) has been around since the beginning of time but for the past decade has experienced an increasing prevalence. TB starts in the lungs but can travel to any organ or structure of the body. The vertebrae are the most often afflicted sites of extra- pulmonary lesions. Pott’s disease is the name given to TB of the spine.

Prepatellar bursitis

Plumbers, carpet layers and other people who spend a lot of time on their knees often experience swelling in the front of the knee. The constant friction irritates a small lubricating sac (bursa) located just in front of the kneecap (patella). The bursa enables the kneecap to move smoothly under the skin. If the bursa becomes inflamed, it fills with fluid and causes swelling at the top of the knee. This condition is called prepatellar bursitis.

Prosthetic joint infection

Infection, one of the most devastating complications of prosthetic joint surgery, can kill or permanently cripple. At the very least, it usually subjects the patient to severe pain and prolonged antibiotic therapy.

Pseudoxanthoma elasticum

Pseudoxanthoma elasticum (PXE) is an inherited connective tissue disorder characterized by progressive calcification and fragmentation of elastic fibers in the skin, the retina, and the cardiovascular system. Typically, cutaneous lesions begin in childhood, but, because of their asymptomatic nature, they are not noted until adolescence. In some individuals, skin lesions do not develop until later in life. This disease is important to recognize early to minimize the occurrence of retinal or gastrointestinal hemorrhage and cardiovascular complications.

Psoriatic arthritis

Psoriatic (sore-EE-AA-tick) arthritis causes pain and swelling in some joints and scaly skin patches on some areas of the body. It is related to the skin condition psoriasis.

Raynaud's phenomenon

Raynaud's phenomenon is a condition resulting from poor circulation in the extremities (i.e., fingers and toes). In a person with Raynaud's phenomenon, when his or her skin is exposed to cold or the person becomes emotionally upset, the blood vessels under the skin tighten and the blood flow slows. This is called vasospasm. Hands and feet have fewer large blood vessels and, therefore, when a vasospasm occurs, it is harder for the blood to keep flowing and these areas may turn blue because less oxygen is reaching the skin. The skin will also feel cold because less blood is reaching the skin to keep it warm. While attacks of vasospasm may last from minutes to hours, only rarely do they cause severe tissue damage.

Reactive arthritis/Reiter's syndrome

Reactive arthritis is a type of arthritis that occurs as a reaction to an infection elsewhere in the body. Reactive arthritis is also known as Reiter's syndrome, and your doctor may refer to it by yet another term, as a seronegative spondyloarthropathy.

Reflex sympathetic dystrophy syndrome

Reflex Sympathetic Dystrophy Syndrome (RSD) - also known as Complex Regional Pain Syndrome (CRPS) - is a chronic neurological syndrome characterized by severe burning pain, pathological changes in bone and skin, excessive sweating, tissue swelling, and extreme sensitivity to touch.

Relapsing polychondritis

Relapsing polychondritis (RP) is an uncommon and severe episodic inflammatory condition involving cartilaginous structures, predominantly those of the ear, nose, and laryngotracheobronchial tree. Other affected structures may include the eye, cardiovascular system, peripheral joints, middle ear, and inner ear.

Retrocalcaneal bursitis

Pain at the posterior heel or ankle most commonly is caused by pathology at either the posterior calcaneus (at the calcaneal insertion site of the Achilles tendon) or associated bursae. Two bursae are located just superior to the insertion of the Achilles (calcaneal) tendon. Anterior or deep to the tendon is the retrocalcaneal (subtendinous) bursa, which is located between the Achilles tendon and the calcaneus. Posterior or superficial to the Achilles tendon is the subcutaneous calcaneal bursa, also called the Achilles bursa. This bursa is located between the skin and posterior aspect of the distal Achilles tendon. Inflammation of either or both of these bursae can cause pain at the posterior heel and ankle region.

Rheumatic fever

Rheumatic (roo-MAT'ik) heart disease is a condition in which the heart valves are damaged by rheumatic fever. Rheumatic fever begins with a strep throat from streptococcal (STREP'to-KOK'al) infection. Rheumatic fever is an inflammatory disease. It can affect many of the body's connective tissues — especially those of the heart, joints, brain or skin. Anyone can get acute rheumatic fever, but it usually occurs in children five to 15 years old. The rheumatic heart disease that results can last for life.

Rheumatoid arthritis

Rheumatoid arthritis (rue-ma-TOYD arth-write-tis) is a chronic disease, mainly characterized by inflammation of the lining, or synovium, of the joints. It can lead to long-term joint damage, resulting in chronic pain, loss of function and disability.

Rheumatoid vasculitis

Rheumatoid Vasculitis (RV) is an unusual complication of longstanding, severe rheumatoid arthritis. The active vasculitis associated with rheumatoid disease occurs in about 1% of this patient population. RV is a manifestation of “extra-articular” (beyond the joint) rheumatoid arthritis and involves the small and medium-sized arteries in the body. In many of its disease features, RV resembles polyarteritis nodosa. Other common extra-articular manifestations of rheumatoid arthritis, such as inflammation in the sac surrounding the heart (pericarditis), inflammation in the lining of the lungs (pleuritis), and interstitial lung disease (resulting in fibrosis or scarring of the lungs).

Rotator cuff tendinitis

Also known as swimmer's shoulder; pitcher's shoulder; shoulder impingement syndrome and tennis shoulder, rotator cuff tendinitis is an inflammation (irritation and swelling) of the tendons of the shoulder.

Sacroiliitis

Sacroiliitis is an inflammation of the sacroiliac joint (a joint formed by a group of vertebrae at the back of the pelvis). Patients are often ill, limping, in pain and showing a decreased range of motion, but the symptoms are still generally vague. The sacroiliac joint is encompassed in a large amount of ligamentous and fibrous tissue for added stability. Conditions that can predispose patients to sacroiliitis include trauma, pregnancy, infections of the skin, osteomyelitis, urinary tract infection, endocarditis and drug addition. This type of infection is seen with some frequency in intravenous drug users.

Salmonella osteomyelitis

Salmonella osteomyelitis is a rare bone infection. The lumbar spine is the most common spinal location affected. The organism most frequently found is a staphylococcus, but the infection can be caused by any other organism. Salmonella osteomyelitis usually develops in immunocompromised patients, most typically in the ones with sickle cell disease.

Sarcoidosis

Sarcoidosis is a disease that causes inflammation of the body's tissues. Inflammation is a basic response of the body to injury and usually causes reddened skin, warmth, swelling, and pain. Inflammation from sarcoidosis is different. In sarcoidosis, the inflammation produces small lumps (also called nodules or granulomas) in the tissues.

Saturnine gout

Saturnine gout is the accumulation of uric acid crystals in the joints, most often in the knees, associated with the absorption of lead into the body. Lead inteferes with the normal excretion of uric acid, and therefore promotes the formation of uric acid crystals which then irritate joint tissues.

Scheuermann's osteochondritis

Also known as Scheuermann’s kyphosis and Scheuermann’s syndrome, spinal osteochondrosis, is the deterioration of the end of a bone from lack of blood supply, with onset at about 12 years of age. It usually involves the seventh and tenth thoracic vertebrae, and presents with backache and spinal curvature. The disturbance affects both sexes, but males more often than females. The course is usually benign and self-limiting but orthopaedic measures are sometimes required.

Scleroderma

Derived from the Greek words "sklerosis," meaning hardness, and "derma," meaning skin, scleroderma literally means hard skin. Though it is often referred to as if it were a single disease, scleroderma is really a symptom of a group of diseases that involve the abnormal growth of connective tissue, which supports the skin and internal organs. It is sometimes used, therefore, as an umbrella term for these disorders. In some forms of scleroderma, hard, tight skin is the extent of this abnormal process. In other forms, however, the problem goes much deeper, affecting blood vessels and internal organs, such as the heart, lungs, and kidneys.

Septic arthritis

Infective arthritis may represent a direct invasion of joint space by a variety of microorganisms, including a variety of bacteria, viruses, mycobacteria, and fungi. Reactive arthritis, a sterile inflammatory process, may be the consequence of an infectious process located somewhere else in the body. Although any infectious agent may cause arthritis, bacterial pathogens are the most rapidly destructive.

Seronegative arthritis

Seronegative arthritides are a heterogeneous group of diseases that includes rheumatoid arthritis with negative rheumatoid factor.

Shigella arthritis

Shigella species are aerobic, nonmotile, glucose-fermenting, gram-negative rods that are highly contagious, causing diarrhea after ingestion of as few as 180 organisms. Shigella species cause damage by 2 mechanisms, invasion of the colonic epithelium, which is dependent on a plasmid-mediated virulence factor, and production of enterotoxin, which is not essential for colitis but enhances virulence. The organism is spread by fecal-oral contact; via infected food or water; during travel; or in long-term care facilities, day care centers, or nursing homes.

Shoulder-hand syndrome

Reflex sympathetic dystrophy syndrome (RSDS) is a condition that features a group of typical symptoms, including pain (often "burning" type), tenderness, and swelling of an extremity associated with varying degrees of sweating, warmth and/or coolness, flushing, discoloration, and shiny skin.

Sickle cell arthropathy

Sickle-cell arthropathy is a deformation of one or more joints related to the presence of sickle cell disease.

Sjogren's syndrome

Sjogren's syndrome classically features a combination of dry eyes, dry mouth, and another disease of the connective tissues, most commonly rheumatoid arthritis.

Sjogren's syndrome is an autoimmune disease, characterized by the abnormal production of extra antibodies in the blood that are directed against various tissues of the body. This particular autoimmune illness is caused by inflammation in the glands of the body. Inflammation of the glands that produce tears (lacrimal glands) leads to decreased water production for tears and eye dryness. Inflammation of the glands that produce the saliva in the mouth (salivary glands, including the parotid glands) leads to mouth dryness.

Sjogren's syndrome that involves the gland inflammation (resulting in dryness of the eyes and mouth, etc.), but not associated with a connective tissue disease, is referred to as primary Sjogren's syndrome. Secondary Sjogren's syndrome involves not only gland inflammation, but is associated with a connective tissue disease, such as rheumatoid arthritis, systemic lupus erythematosus, or scleroderma.

Slipped capital femoral epiphysis

Slipped capital femoral epiphysis (SCFE) is an unusual disorder of the adolescent hip. It is not rare. For reasons that are not well understood, the ball at the upper end of the femur (thigh bone) slips off in a backward direction. This is due to weakness of the growth plate. Most often, it develops during periods of accelerated growth, shortly after the onset of puberty.

The condition is diagnosed based on a careful history, physical examination, observation of the gait/walking pattern and hip X-rays. The X-rays help confirm the diagnosis by demonstrating that the upper end of the thigh bone does not line up with the portion called the femoral neck.

Spinal stenosis

Spinal stenosis is a narrowing of spaces in the spine (backbone) that results in pressure on the spinal cord and/or nerve roots. This disorder usually involves the narrowing of one or more of three areas of the spine: (1) the canal in the center of the column of bones (vertebral or spinal column) through which the spinal cord and nerve roots run, (2) the canals at the base or roots of nerves branching out from the spinal cord, or (3) the openings between vertebrae (bones of the spine) through which nerves leave the spine and go to other parts of the body. The narrowing may involve a small or large area of the spine. Pressure on the lower part of the spinal cord or on nerve roots branching out from that area may give rise to pain or numbness in the legs. Pressure on the upper part of the spinal cord (that is, the neck area) may produce similar symptoms in the shoulders, or even the legs.

Spondylolysis

The most common X-ray identified cause of low back pain in adolescent athletes is a stress fracture in one of the bones (vertebrae) that make up the spinal column. Technically, this condition is called spondylolysis (spon-dee-low-lye-sis). It usually affects the fifth lumbar vertebra in the lower back, and much less commonly, the fourth lumbar vertebra.

If the stress fracture weakens the bone so much that it is unable to maintain its proper position, the vertebra can start to shift out of place. This condition is called spondylolisthesis (spon-dee-low-lis-thee-sis). If too much slippage occurs, the bones may begin to press on nerves and surgery may be necessary to correct the condition.

Staphylococcus arthritis

Infective arthritis may represent a direct invasion of joint space by a variety of microorganisms, including a variety of bacteria, viruses, mycobacteria, and fungi. Reactive arthritis, a sterile inflammatory process, may be the consequence of an infectious process located somewhere else in the body. Although any infectious agent may cause arthritis, bacterial pathogens are the most rapidly destructive.

Stickler syndrome

Stickler syndrome is a subtype of collagenopathy, types II and XI. A characteristic feature of Stickler syndrome is a somewhat flattened facial appearance. This is caused by underdeveloped bones in the middle of the face, including the cheekbones and the bridge of the nose. A particular group of physical features, called Robin sequence, is common in children with Stickler syndrome. Robin sequence includes a U-shaped cleft palate (an opening in the roof of the mouth) with a tongue that is too large for the space formed by the small lower jaw. Children with a cleft palate are also prone to frequent ear infections and swallowing difficulties. Nearsightedness and hearing loss can also accompany the disease.

Subacute cutaneous lupus

Subacute cutaneous lupus erythematosus (SCLE) is a nonscarring non–atrophy-producing light-sensitive skin condition. SCLE may occur in patients with systemic lupus erythematosus (SLE), Sjögren syndrome, and deficiency of the second component of complement (C2d), or it may be drug induced. Some patients also have the lesions of discoid lupus erythematosus (DLE), and some may develop small vessel vasculitis.

Patients with SCLE frequently fulfill 4 or more of the criteria used to classify SLE (see Systemic Lupus Erythematosus). Serologic abnormalities are common. Therapy with sunscreens, topical corticosteroids, and antimalarials usually is effective.

Sweet's syndrome

Also known as Sweet's disease, acute febrile neutrophilic dermatosis, and febrile neutrophilic dermatosis, Sweet’s syndrome is a skin disease of unknown aetiology characterized by abrupt onset of fever, raised painful scaly patches of skin on the limbs, face, and neck and an increase in white blood cells.

Additional symptoms may include headache, joint pain, and swelling and hardening of the eyes. Upper respiratory tract infection, tonsillitis, or influenza like illness often precede the appearance of skin lesions.

Sydenham's chorea

Also known as Chorea St. Viti, St. Vitus’ dance, Sydenham’s disease, Sydenham’s syndrome or acute chorea, chorea infectiosa, chorea minor, chorea naturalis, chorea rheumatica, infectious chorea, minor chorea, or rheumatic chorea, Sydenham’s chorea is an infectious disease of the central nervous system commonly occurring between 5 and 15 years of age that is characterized by involuntary purposeless contractions of the muscles of the trunk and extremities, initially in one limb; face movements that simulate smirking expressions, anxiety; impairment of memory and sometimes of speech. Besides in rheumatic fever, it has also been reported in association with hyperthyroidism, systemic lupus erythematosus and some other common erythemas.

Syphilitic arthritis

Joint disease associated with congenital and acquired syphilitic infections is now rare. In infants with congenital disease, musculoskeletal complaints are related to periostitis and osteochondritis.

Systemic lupus erythematosus (SLE)

Systemic Lupus Erythematosus (sis-TEM-ick LOO-pus err-ah-theme-ahTOE-sus) is a chronic (long-lasting) rheumatic disease which affects joints, muscles and other parts of the body. Lupus involves inflammation (the immune system's response to kill foreign agents, virus, bacteria). Systemic lupus erythematosus involves chronic inflammation that can affect many parts of the body, including the heart, lungs, skin, joints, blood-forming organs, kidneys and nervous system.

• There are several types of lupus:
• Discoid lupus affects the skin.
• Drug-induced lupus occurs because of a reaction to drugs. Symptoms, however, disappear once the drugs are discontinued.
• Crossover, or overlap, syndromes indicate features that overlap with another rheumatic disease.

Takayasu's arteritis

The first case of Takayasu’s arteritis was described in 1908 by Dr. Mikito Takayasu at the Annual Meeting of the Japan Ophthalmology Society. Dr. Takayasu described a peculiar "wreathlike" appearance of blood vessels in the back of the eye (retina). Two Japanese colleagues at the same meeting reported similar eye findings in patients whose wrist pulses were absent. It is now known that the blood vessel malformations that occur in the retina are a response (new blood vessel growth) to arterial narrowings in the neck, and that the absence of pulses noted in some patients occur because of narrowings of blood vessels to the arms. The eye findings described by Dr. Takayasu are rarely seen in patients from North America.

Tarsal tunnel syndrome

Tarsal tunnel syndrome is caused by the entrapment of the tibial nerve. The tibial nerve follows a long, curving route down the back of the leg to the ankle, where it turns and curls below the inside of the ankle. There are four compartments in this region. In three of them, muscles are routed from the leg to the foot. In the fourth, the tibial nerve and the posterior tibial artery are surrounded by muscles. Along the top of these structures lies the laciniate ligament, which forms the roof of the four compartments. There is little room for expansion if any of these structures becomes enlarged or if a foreign object intrudes into the area. If anything impinges on the space occupied by the tibial nerve (i.e., the tarsal tunnel), entrapment occurs.

Tennis elbow

Tennis elbow is an injury to the muscles and tendons on the outside (lateral aspect) of the elbow that results from overuse or repetitive stress. The narrowing of the muscle bellies of the forearm as they merge into the tendons create highly focused stress where they insert into the bone of the elbow.

Tietze's (Tietse’s) syndrome

Also known as chondrodynia costosternalis, costal chondritis syndrome, costochondritis, chondropathia tuberosa, costochondral junction syndrome and peristernal perichondritis, Tietze’s syndrome is an inflammation of the costochondral cartilages in the rib and sternal areas. Tietze's syndrome and costochondritis are not identical, as the Tietze syndrome is associated with swelling, whereas costochondritis is not.

Transient osteoporosis

Transient osteoporosis of the hip is a condition that occurs for unknown reasons. The condition is characterized by spontaneous onset of hip pain associated with X-Ray evidence of osteoporosis of the hip. Transient osteoporosis of the hip usually resolves on its own within six months to a year.

Traumatic arthritis

Traumatic arthritis is a joint disease resulting from direct or indirect injury to a joint. As bones or joint soft tissues heal, various structures may regrow abnormally, causing friction and damage.

Trochanteric bursitis

Trochanteric bursitis is characterized by painful inflammation of the bursa located just superficial to the greater trochanter of the femur. Patients typically complain of lateral hip pain, although the hip joint itself is not involved. The pain may radiate down the lateral aspect of the thigh.

Tuberculosis arthritis

Tuberculous arthritis is an infection of the joints caused by tuberculosis. (See also spondylitis.)

Arthritis of Ulcerative colitis

Inflammatory Bowel Disease. IBD is a general term that covers two distinct disorders: Ulcerative Colitis (UC) and Crohn's disease (CD). However, some evidence suggests they are part of a biologic continuum. Arthritis (the spine is commonly affected) and osteoporosis are common extraintestinal complications of IBD.

Undifferentiated connective tissue syndrome (UCTS)

Several efforts have been made to group and label these coexisting autoimmune disorders. The term Overlap Syndromes has been used to describe the group of patients exhibit features of more than one established autoimmune disorders. Several combinations of definite connective tissue diseases have been reported.

Undifferentiated connective tissue disease (UCTS) is used for patients who have features strongly suggestive of connective tissue disease but not definitely diagnostic of any one disorder.

Mixed connective tissue disease (MCTD) was initially described by Sharp as a new syndrome with features of systemic lupus erythematosus (SLE), systemic sclerosis, polymyositis and rheumatoid arthritis and high titers of circulating antibody to nuclear ribonucleoprotein (RNP) antigen. It should be noted that the classification of overlap, UCTS and MCTD is based on descriptive phenomena. This classification usually has only a loose statistical relationship with prognosis and outcome and is frequently confusing when applied to the individual patient. Multiple autoimmune syndromes (MAS) is the combination of at least three autoimmune diseases in the same patient. This new classification based on 91 reported cases of morbid associations concerns the grouping of autoimmune conditions in the same patient.

Urticarial vasculitis

Urticarial vasculitis is an eruption of reddened bumps on the skin that clinically resemble hives but histologically show changes in white blood cells. Systemic symptoms can include swelling of the heart, joint pain, chest pain, fever and pulmonary disease or renal disease. The hypocomplementemic form more often is associated with systemic symptoms and has been linked to connective-tissue disease (ie, systemic lupus erythematosus [SLE]).

Viral arthritis

Arthritis may be a symptom of many viral illnesses. The duration is usually short, and it usually disappears on its own without any lasting effects. It may be associated with mumps, rubella, human parvovirus, and Hepatitis B. It may also occur after immunization with rubella vaccine. This is a common form of childhood joint discomfort.

Wegener's granulomatosis

Wegener's granulomatosis is an uncommon disease, in which the blood vessels are inflamed (vasculitis). This inflammation damages important organs of the body by limiting blood flow to those organs and destroying normal tissue.

Although the disease can involve any organ system, Wegener's granulomatosis mainly affects the respiratory tract (sinuses, nose, trachea [windpipe], and lungs) and kidneys. This disorder can affect people at any age and strikes men and women equally. It is rare in African Americans compared to Caucasians. Health experts do not know what causes Wegener's granulomatosis.

Whipple's disease

Whipple's disease is a rare infectious disease that typically infects the bowel. It causes malabsorption primarily but may affect any part of the body including the heart, lungs, brain, joints, and eyes. It interferes with the body's ability to absorb certain nutrients. Whipple's disease causes weight loss, incomplete breakdown of carbohydrates or fats, and malfunctions of the immune system.

Wilson's disease

Wilson's disease causes the body to retain copper. The liver of a person who has Wilson's disease does not release copper into bile as it should. Bile is a liquid produced by the liver that helps with digestion. As the intestines absorb copper from food, the copper builds up in the liver and injures liver tissue. Eventually, the damage causes the liver to release the copper directly into the bloodstream, which carries the copper throughout the body. The copper buildup leads to damage in the kidneys, brain, and eyes. If not treated, Wilson's disease can cause severe brain damage, liver failure, and death.

Yersinial arthritis

A disease of joints – acute mono- or oligoarthritis – caused by Yersinia enterocolitica or Yersinia pseudotuberculosis.