MCT8-specific thyroid hormone cell transporter deficiency (THCT deficiency) is an inherited disorder that is characterized by severe mental retardation, an impaired ability to speak, diminished muscle tone (hypotonia), and/or movement abnormalitie...

MCT8-specific thyroid hormone cell transporter deficiency (THCT deficiency) is an inherited disorder that is characterized by severe mental retardation, an impaired ability to speak, diminished muscle tone (hypotonia), and/or movement abnormalitie...

Amyotrophic lateral sclerosis facts Amyotrophic lateral sclerosis is a rapidly progressive, invariably fatal neurological disease that attacks the nerve cells responsible for controlling voluntary muscles. Amyotrophic late...

Ankylosing spondylitis facts Ankylosing spondylitis belongs to a group of arthritis conditions that tend to cause chronic inflammation of the spine (spondyloarthropathies). Ankylosing spondylitis affects males two to three...

Polymyalgia rheumatica is a rare inflammatory disease characterized by muscle pain (myalgia), stiffness, and additional generalized systemic symptoms such as fatigue, low-grade fever, and/or a general feeling of ill health (malaise). Polymyalgia r...

Arthritis is the swelling and tenderness of one or more joints. The main symptoms of arthritis are joint pain and stiffness, which typically worsen with age. The most common types of arthritis are osteoarthritis and rheumatoid arthritis. O...

Arthritis is the swelling and tenderness of one or more joints. The main symptoms of arthritis are joint pain and stiffness, which typically worsen with age. The most common types of arthritis are osteoarthritis and rheumatoid arthritis. O...

Infectious arthritis is an inflammation of one or more joints that occurs as a result of infection by bacteria, viruses or, less frequently, fungi or parasites. The symptoms of Infectious arthritis depend upon which agent has caused the infection ...

Juvenile idiopathic arthritis, formerly known as juvenile rheumatoid arthritis, is the most common type of arthritis in children under the age of 16. Juvenile idiopathic arthritis can cause persistent joint pain, swelling and stiffness. So...

Familial articular chondrocalcinosis is a rare inherited metabolic disorder characterized by deposits of calcium pyrophosphate dihydrate crystals (CPPD) in one or more joint cartilages resulting in eventual damage to the joints. Symptoms may devel...

Gordon syndrome is an extremely rare disorder that belongs to a group of genetic disorders known as the distal arthrogryposes. These disorders typically involve stiffness and impaired mobility of certain joints of the lower arms and legs (distal e...

Camptomelic syndrome is a rare congenital disorder in which multiple anomalies are present. It is characterized by bowing and angular shape of the long bones of the legs, especially the tibia; multiple minor anomalies of the face; cleft palate; ot...

Collagenous colitis is a rare digestive disorder that primarily affects females and typically becomes apparent during middle age. The disorder is characterized by inflammatory changes of the mucous membranes (mucosa) of the colon (colitis) and abn...

Mixed connective tissue disease facts Connective tissues are the framework of the cells of the body. Mixed connective tissue disease is an "overlap" combination of connective tissue diseases. Diagnosis of mixed c...

Camurati-Engelmann disease is a rare genetic disorder characterized by progressive widening and malformation of the shafts of the long bones (diaphyseal dysplasia). Major symptoms may include bone pain, particularly in the legs; skeletal abnormali...

Dyggve-Melchior-Clausen (DMC) syndrome is a rare, progressive genetic disorder characterized by abnormal skeletal development, microcephaly and intellectual disability. The condition was first reported by Dyggve, Melchior and Clausen in 1962 in th...

Dysplasia epiphysealis hemimelica, also known as Trevor disease, is a rare skeletal developmental disorder of childhood. It is characterized by an overgrowth of cartilage on the ends (epiphyses) of the long bones of the arms and legs and the bones...

Erythema multiforme (EM) is the name applied to a group of hypersensitivity disorders, affecting mostly children and young adults, and characterized by symmetric red, patchy lesions, primarily on the arms and legs. The cause is unknown, but EM fre...

Cryptococcosis is caused by a fungus known as Cryptococcosis neoformans. The infection may be spread to humans through contact with pigeon droppings or unwashed raw fruit. Contact with an infected individual may also spread the infection. Individu...

Familial idiopathic basal ganglia calcification (FIBGC) is a rare neurological disorder characterized by the presence of abnormal calcium deposits (calcifications) of unknown cause. Associated symptoms include progressive deterioration of cognitiv...

Familial idiopathic basal ganglia calcification (FIBGC) is a rare neurological disorder characterized by the presence of abnormal calcium deposits (calcifications) of unknown cause. Associated symptoms include progressive deterioration of cognitiv...

Frozen shoulder facts Frozen shoulder is the result of scarring, thickening, and shrinkage of the joint capsule. Any injury to the shoulder can lead to a frozen shoulder. A frozen shoulder is usually diagnosed du...

Krabbe's Leukodystrophy is a rare inherited lipid storage disorder caused by a deficiency of the enzyme galactocerebrosidase (GALC), which is necessary for the breakdown (metabolism) of the sphingolipids galactosylceremide and psychosine. Failure ...

Krabbe's Leukodystrophy is a rare inherited lipid storage disorder caused by a deficiency of the enzyme galactocerebrosidase (GALC), which is necessary for the breakdown (metabolism) of the sphingolipids galactosylceremide and psychosine. Failure ...

Krabbe's Leukodystrophy is a rare inherited lipid storage disorder caused by a deficiency of the enzyme galactocerebrosidase (GALC), which is necessary for the breakdown (metabolism) of the sphingolipids galactosylceremide and psychosine. Failure ...

Pseudo-Hurler polydystrophy (mucolipidosis type III) is a rare genetic metabolic disorder characterized by a defective enzyme known as UPD-N-acetylglucosamine-1-phosphotransferase. This defective enzyme ultimately results in the accumulation of ce...

L1 syndrome is an inherited, X-linked disorder occurring in males that primarily affects the nervous system. The disease is mainly characterized by hydrocephalus (increased fluid in the center of the brain), spasticity of the lower limbs (muscle s...

Krabbe's Leukodystrophy is a rare inherited lipid storage disorder caused by a deficiency of the enzyme galactocerebrosidase (GALC), which is necessary for the breakdown (metabolism) of the sphingolipids galactosylceremide and psychosine. Failure ...

Gout is a type of arthritis that causes inflammation, usually in one joint, that begins suddenly. Gouty arthritis is caused by the deposition of crystals of uric acid in a joint. Gout can cause symptoms and signs such as ...

Gout is a type of arthritis that causes inflammation, usually in one joint, that begins suddenly. Gouty arthritis is caused by the deposition of crystals of uric acid in a joint. Gout can cause symptoms and signs such as ...

Sjogren-Larsson syndrome is an inherited disorder characterized by scaling skin (ichthyosis), mental retardation, speech abnormalities, and spasticity. Affected infants develop various degrees of reddened skin with fine scales soon after birth. Af...

Familial idiopathic basal ganglia calcification (FIBGC) is a rare neurological disorder characterized by the presence of abnormal calcium deposits (calcifications) of unknown cause. Associated symptoms include progressive deterioration of cognitiv...

West syndrome is a type of epilepsy characterized by spasms, abnormal brain wave patterns called hypsarrhythmia and sometimes mental retardation. The spasms that occur may range from violent jackknife or "salaam" movements where the whole body ben...

West syndrome is a type of epilepsy characterized by spasms, abnormal brain wave patterns called hypsarrhythmia and sometimes mental retardation. The spasms that occur may range from violent jackknife or "salaam" movements where the whole body ben...

The spinal muscular atrophies (SMAs), are characterized by degeneration of nerve cells (motor nuclei) within the lowest region of the brain (lower brainstem) and certain motor neurons in the spinal cord (anterior horn cells) leading to muscle weak...

Acquired neuromyotonia is an inflammatory disorder characterized by abnormal nerve impulses from the peripheral nerves that result in continuous muscle fiber activity. Affected individuals often experience progressive muscle stiffness and cramping...

Acquired neuromyotonia is an inflammatory disorder characterized by abnormal nerve impulses from the peripheral nerves that result in continuous muscle fiber activity. Affected individuals often experience progressive muscle stiffness and cramping...

Osteonecrosis, also known as avascular necrosis, is a disease resulting from the temporary or permanent loss of the blood supply to the bones. Without blood, the bone tissue dies and causes the bone to collapse. If the process involves the bones n...

wJansen type metaphyseal chondrodysplasia is an extremely rare progressive disorder in which portions of the bones of the arms and legs develop abnormally with unusual cartilage formations and subsequent abnormal bone formation at the large (bulbo...

Jansen type metaphyseal chondrodysplasia is an extremely rare progressive disorder in which portions of the bones of the arms and legs develop abnormally with unusual cartilage formations and subsequent abnormal bone formation at the large (bulbou...

Jansen type metaphyseal chondrodysplasia is an extremely rare progressive disorder in which portions of the bones of the arms and legs develop abnormally with unusual cartilage formations and subsequent abnormal bone formation at the large (bulbou...

Jaw clicking is a common symptom of temporomandibular joint (TMJ) disorder, which is a condition that affects the jaw joint and surrounding muscles. When a person with TMJ disorder opens or closes their mouth, the jaw joint may make a clicking or ...

Jaw pain is discomfort or soreness in the jaw area, which can be caused by a variety of factors such as teeth grinding, temporomandibular joint (TMJ) disorder, dental issues, or muscle tension. It can range from mild to severe and may be accompani...

Kienbock Disease is an acquired bone disorder. Abnormalities of the lunate bone in the wrist develops following an injury or inflammation. Recurrent pain and stiffness occur in conjunction with thickening, swelling and tenderness in soft tissue ov...

Knee bursitis facts A bursa is a fluid-filled sac that functions as a gliding surface to reduce friction between moving tissues of the body. There are three major bursae of the knee. Bursitis is usually not infec...

Knee pain facts Knee pain is a common problem with many causes, from acute injuries to medical conditions. Knee pain can be localized or diffuse throughout the knee. Knee pain is often accompanied by physical res...

Kniest dysplasia is one of several forms of dwarfism that is caused by a change (mutation) in a gene known as COL2A1. This gene is involved in the production of a particular protein that forms type 2 collagen, which is essential for the normal dev...

Kniest dysplasia is one of several forms of dwarfism that is caused by a change (mutation) in a gene known as COL2A1. This gene is involved in the production of a particular protein that forms type 2 collagen, which is essential for the normal dev...

Hyperekplexia is a rare hereditary, neurological disorder that may affect infants as newborns (neonatal) or prior to birth (in utero). It may also affect children and adults. Individuals with this disorder have an excessive startle reaction (eye b...

Kyphosis facts There are three main types of kyphosis: postural, Scheuermann's, and congenital. Most cases of kyphosis do not require any treatment. Physical therapy and exercise are often effective in postural a...

Legg-Calvé-Perthes Disease (LCPD) is one of a group of disorders known as the Osteochondroses. The Osteochondroses typically are characterized by degeneration (avascular necrosis) and subsequent regeneration of the growing end of a bone (ep...

Von Hippel-Lindau syndrome (VHL) is an autosomal dominant genetic disorder characterized by the abnormal growth of blood vessels in certain parts of the body (angiomatosis). Very small blood vessels (capillaries) "knot" together to form benign gro...

Low back pain facts Functions of the low back, or lumbar area, include structural support, movement, and protection of certain body tissues. Pain in the low back can be a result of conditions affecting the bony lumbar spin...

Osteopetrosis may be inherited as either a dominant or recessive trait and is marked by increased bone density, brittle bones, and, in some cases, skeletal abnormalities. Although symptoms may not initially be apparent in people with mild forms of...

Stiff-person syndrome (SPS) is a rare acquired neurological disorder characterized by progressive muscle stiffness (rigidity) and repeated episodes of painful muscle spasms. Muscular rigidity often fluctuates (i.e., grows worse and then improves) ...

The Mucopolysaccharidoses (MPS Disorders) are a group of rare genetic disorders caused by the deficiency of one of the lysosomal enzymes, resulting in an inability to metabolize complex carbohydrates (mucopolysaccharides) into simpler molecules. H...

Muscle sprains and strains facts A sprain is abnormal stretching or tearing of a ligament that supports a joint. A strain is abnormal stretching or tearing of a muscle or tendon. Sprains and strains may be caused...

Myofascial pain syndrome facts Muscle pain, tenderness, and spasm are characteristics of myofascial pain syndrome. Myofascial pain syndrome typically affects muscle in asymmetric areas of the body. The precise ca...

Pain located in the neck is a common medical condition. Neck pain can come from a number of disorders and diseases and can involve any of the tissues in the neck. Examples of common conditions causing neck pain are degenerative disc disease, neck ...

Nonketotic hyperglycinemia is an inborn error of metabolism characterized by the accumulation of large amounts of the amino acid glycine in blood, urine and, particularly, the cerebrospinal fluid (CSF). The metabolic block occurs in the conversion...

Oral fibrosis, also known as oral submucous fibrosis, is a chronic, progressive condition that affects the mucous membranes in the mouth. It is characterized by the formation of fibrous bands of tissue in the mouth, which can lead to restricted mo...

Osteoarthritis facts Osteoarthritis is a joint inflammation that results from cartilage degeneration. Osteoarthritis can be caused by aging, heredity, and injury from trauma or disease. The most common symptom of...

Osteoarthritis facts Osteoarthritis is a joint inflammation that results from cartilage degeneration. Osteoarthritis can be caused by aging, heredity, and injury from trauma or disease. The most common symptom of...

Osteochondritis dissecans facts Osteochondritis dissecans is a joint condition whereby a variable amount of bone and its adjacent cartilage loses its blood supply. The cause of osteochondritis dissecans is often unknown....

Different types of manual therapy, or mobilization, can be used to treat people with spinal alignment problems. For acute musculoskeletal pain, these techniques have been shown to speed recovery. In patients with musculoskeletal disorders ...

Polio, short for poliomyelitis, is a highly contagious viral infection that can lead to paralysis, muscle weakness, and in severe cases, death. It primarily affects children under the age of 5. The virus is spread through contaminated food and wat...

Polymyalgia rheumatica and giant cell arteritis facts Polymyalgia rheumatica causes pain and stiffness in muscles and joints. Polymyalgia rheumatica is diagnosed by characteristic symptoms associated with abnormal blood te...

Acquired neuromyotonia is an inflammatory disorder characterized by abnormal nerve impulses from the peripheral nerves that result in continuous muscle fiber activity. Affected individuals often experience progressive muscle stiffness and cramping...

Reflex sympathetic dystrophy syndrome (RSDS), also known as complex regional pain syndrome, is a rare disorder of the sympathetic nervous system that is characterized by chronic, severe pain. The sympathetic nervous system is that part of the auto...

Reflex sympathetic dystrophy (RSD) facts Reflex sympathetic dystrophy (RSD) is characterized by a group of symptoms including pain (often "burning" type), tenderness, and swelling of an extremity associated with varying degrees of s...

Reflex sympathetic dystrophy syndrome (RSDS), also known as complex regional pain syndrome, is a rare disorder of the sympathetic nervous system that is characterized by chronic, severe pain. The sympathetic nervous system is that part of the auto...

Rheumatoid arthritis is a chronic inflammatory disorder that can affect more than just your joints. In some people, the condition can damage a wide variety of body systems, including the skin, eyes, lungs, heart and blood vessels. An autoi...

Rheumatoid arthritis is a chronic inflammatory disorder that can affect more than just your joints. In some people, the condition can damage a wide variety of body systems, including the skin, eyes, lungs, heart and blood vessels. An autoi...

Stiff-person syndrome (SPS) is a rare acquired neurological disorder characterized by progressive muscle stiffness (rigidity) and repeated episodes of painful muscle spasms. Muscular rigidity often fluctuates (i.e., grows worse and then improves) ...

Familial idiopathic basal ganglia calcification (FIBGC) is a rare neurological disorder characterized by the presence of abnormal calcium deposits (calcifications) of unknown cause. Associated symptoms include progressive deterioration of cognitiv...

Diffuse idiopathic skeletal hyperostosis (DISH), also known as Forestier's disease, affects the ligaments around the spine. Sections of the ligaments turn into bone in this disorder, which is considered to be a form of degenerative arthritis. ...

Spinal headaches are a fairly common complication in those who undergo a spinal tap (lumbar puncture) or spinal anesthesia. Both procedures require a puncture of the membrane that surrounds the spinal cord and, in the lower spine, the lumbar and s...

Tetanus, also known as lockjaw, is a serious bacterial infection caused by the bacterium Clostridium tetani. The bacteria usually enter the body through a wound or cut, where they produce a toxin that affects the nervous system, leading to muscle ...

Torus mandibularis is a bony growth that develops on the inner surface of the lower jaw, near the premolar and molar teeth. It is a benign, non-cancerous growth that is usually painless and does not require treatment unless it causes discomfort or...

Trismus, also known as lockjaw, is a condition characterized by difficulty opening the mouth due to muscle spasms in the jaw. It can be caused by a variety of factors, including dental procedures, trauma to the jaw, infections, or neurological con...

Diffuse idiopathic skeletal hyperostosis (DISH), also known as Forestier's disease, affects the ligaments around the spine. Sections of the ligaments turn into bone in this disorder, which is considered to be a form of degenerative arthritis. ...

General DiscussionRomano-Ward syndrome is an inherited heart (cardiac) disorder characterized by abnormalities affecting the electrical system of the heart. The severity of Romano-Ward syndrome varies greatly from case to case. Some indiv...

Whiplash is a relatively common injury that is often ignored or mistreated due to lack of understanding of the condition. Whiplash is usually the result of a rear impact while in a stationary position. Early range of motio...

L1 syndrome is an inherited, X-linked disorder occurring in males that primarily affects the nervous system. The disease is mainly characterized by hydrocephalus (increased fluid in the center of the brain), spasticity of the lower limbs (muscle s...