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X-linked Charcot–Marie–Tooth Disease
X-linked Charcot–Marie–Tooth disease is a group of genetic disorders and a type of Charcot–Marie–Tooth disease characterized by sensory loss associated with muscle weakness and atrophy alongside many other symptoms. Signs and symptoms Symptoms vary between subtypes, but generally they can be condensed into a basic summary: individuals with this condition have symptoms that, once present, progress over time (severity increases over time), these include: muscle weakness and muscle atrophy, atrophy of the distal extremities (mostly involving feet, legs, and the thenar eminence of the hands), loss of sensation of the distal limbs, loss of reflexes of the deep tendon, pes cavus, high-arched feet, and (less commonly) scoliosis. Symptoms that are less frequent among X-linked CMT disease patients include dysfunctions of the transient central nervous system which are associated with dysphagia, dysarthria, ataxia, generalized body weakness, aphasia, and somnolence. Severe cases ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medical Genetics
Medical genetics is the branch of medicine that involves the diagnosis and management of hereditary disorders. Medical genetics differs from human genetics in that human genetics is a field of scientific research that may or may not apply to medicine, while medical genetics refers to the application of genetics to medical care. For example, research on the causes and inheritance of genetic disorders would be considered within both human genetics and medical genetics, while the diagnosis, management, and counselling people with genetic disorders would be considered part of medical genetics. In contrast, the study of typically non-medical phenotypes such as the genetics of eye color would be considered part of human genetics, but not necessarily relevant to medical genetics (except in situations such as albinism). ''Genetic medicine'' is a newer term for medical genetics and incorporates areas such as gene therapy, personalized medicine, and the rapidly emerging new medical specia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Areflexia
Hyporeflexia is the reduction or absence of normal bodily reflexes. It can be detected through the use of a reflex hammer and is the opposite of hyperreflexia. Hyporeflexia is generally associated with a deficit in the lower motor neurons (at the alpha motor neurons from the spinal cord to a muscle), whereas hyperreflexia is often attributed to lesions in the upper motor neurons (along the long, motor tracts from the brain). The upper motor neurons are thought to inhibit the reflex arc, which is formed by sensory neurons from intrafusal fibers of muscles, lower motor neurons (including alpha and gamma motor fibers) and appurtenant interneurons. Therefore, damage to lower motor neurons will subsequently result in hyporeflexia and/or areflexia. In spinal shock, which is commonly seen in the transection of the spinal cord, hyporeflexia can transiently occur below the level of the lesion and can later become hyperreflexic. Cases of severe muscle atrophy or destruction may render ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steppage Gait
Steppage gait (high stepping, neuropathic gait) is a form of gait abnormality characterised by foot drop or ankle equinus due to loss of dorsiflexion. The foot hangs with the toes pointing down, causing the toes to scrape the ground while walking, requiring someone to lift the leg higher than normal when walking. Foot drop can be caused by damage to the deep fibular nerve. Conditions associated with a steppage gait * Foot drop * Charcot–Marie–Tooth disease * Polio * Multiple sclerosis * Syphilis * Guillain–Barré syndrome * Spinal disc herniation * Anterior Compartment Muscle Atrophy * Deep fibular nerve injury * Spondylolisthesis Spondylolisthesis is when one spinal vertebra slips out of place compared to another. While some medical dictionaries define spondylolisthesis specifically as the forward or anterior displacement of a vertebra over the vertebra inferior to it (o ... * Slipped Femoral Epiphysis * ALS/PLS References External links A video of a neuropathic gait ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Claw Toes
A hammer toe, hammertoe or contracted toe is a deformity of the muscles and ligaments of the Anatomical terms of location#Proximal and distal, proximal Interphalangeal articulations of foot, interphalangeal joint of the second, third, fourth, or fifth toe, bending it into a shape resembling a hammer. In the early stage, a flexible hammertoe is movable at the joints; a rigid hammertoe joint cannot be moved and usually requires surgery. Reviewed March 31, 2019 Mallet toe is a similar condition affecting the Anatomical terms of location#Proximal and distal, distal interphalangeal joint. Claw toe is another similar condition, with dorsiflexion of the proximal phalanx on the lesser Metatarsophalangeal articulations, metatarsophalangeal joint, combined with flexion of both the proximal and distal interphalangeal joints. Claw toe can affect the second, third, fourth, or fifth toes. Types There are three types of hammer toe, as categorized by podiatrists. *Flexible hammer toes are whe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optic Neuropathy
Optic neuropathy is damage to the optic nerve from any cause. The optic nerve is a bundle of millions of fibers in the retina that sends visual signals to the brain. Damage and death of these nerve cells, or neurons, leads to characteristic features of optic neuropathy. The main symptom is loss of vision, with colors appearing subtly washed out in the affected eye. A pale disc is characteristic of long-standing optic neuropathy. In many cases, only one eye is affected and a person may not be aware of the loss of color vision until the examiner asks them to cover the healthy eye. Optic neuropathy is often called optic atrophy, to describe the loss of some or most of the fibers of the optic nerve. Signs and symptoms The main symptom is loss of vision, with colors appearing subtly washed out in the affected eye. In many cases, only one eye is affected and the person may not be aware of the loss of color vision until the examiner asks them to cover the healthy eye. People may also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Congenital Hearing Loss
Congenital hearing loss is a hearing loss present at birth. It can include hereditary hearing loss or hearing loss due to other factors present either in-utero (prenatal) or at the time of birth. Genetic factors Genetic factors are thought to cause more than 50% of all incidents of congenital hearing loss. Genetic hearing loss may be autosomal dominant, autosomal recessive, or X-linked (related to the sex chromosome). Hearing loss Autosomal dominant hearing loss In autosomal dominant hearing loss, one parent who carries the dominant gene for hearing loss and typically has a hearing loss passes it on to the child. In this case there is at least a 50% probability that the child will also have a hearing loss. The probability is higher if both parents have the dominant gene (and typically both have hearing loss) or if both grandparents on one side of the family have hearing loss due to genetic causes. Because at least one parent usually has a hearing loss, there is prior exp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hammer Toes
A hammer toe, hammertoe or contracted toe is a deformity of the muscles and ligaments of the proximal interphalangeal joint of the second, third, fourth, or fifth toe, bending it into a shape resembling a hammer. In the early stage, a flexible hammertoe is movable at the joints; a rigid hammertoe joint cannot be moved and usually requires surgery. Reviewed March 31, 2019 Mallet toe is a similar condition affecting the distal interphalangeal joint. Claw toe is another similar condition, with dorsiflexion of the proximal phalanx on the lesser metatarsophalangeal joint, combined with flexion of both the proximal and distal interphalangeal joints. Claw toe can affect the second, third, fourth, or fifth toes. Types There are three types of hammer toe, as categorized by podiatrists. *Flexible hammer toes are where patients are still able to bend and move the affected toes, but where a noticeable curl has begun to form. *Semi-rigid hammer toes are where the affected toes are hard t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spastic Paraparesis
Hereditary spastic paraplegia (HSP) is a group of inherited diseases whose main feature is a progressive gait disorder. The disease presents with progressive stiffness (spasticity) and contraction in the lower limbs. HSP is also known as hereditary spastic paraparesis, familial spastic paraplegia, French settlement disease, Strumpell disease, or Strumpell-Lorrain disease. The symptoms are a result of dysfunction of long axons in the spinal cord. The affected cells are the primary motor neurons; therefore, the disease is an upper motor neuron disease. HSP is not a form of cerebral palsy even though it physically may appear and behave much the same as spastic diplegia. The origin of HSP is different from cerebral palsy. Despite this, some of the same anti-spasticity medications used in spastic cerebral palsy are sometimes used to treat HSP symptoms. HSP is caused by defects in transport of proteins, structural proteins, cell-maintaining proteins, lipids, and other substances ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paresthesia
Paresthesia is a sensation of the skin that may feel like numbness (''hypoesthesia''), tingling, pricking, chilling, or burning. It can be temporary or Chronic condition, chronic and has many possible underlying causes. Paresthesia is usually painless and can occur anywhere on the body, but most commonly in the arms and legs. The most familiar kind of paresthesia is the sensation known as ''pins and needles'' after having a limb "fall asleep" (''obdormition''). A less common kind is formication, the sensation of insects crawling on the skin. Causes Transient Paresthesias of the hands, feet, legs, and arms are common transient symptoms. The briefest electric shock type of paresthesia can be caused by tweaking the ulnar nerve near the elbow; this phenomenon is colloquially known as bumping one's "funny bone". Similar brief shocks can be experienced when any other nerve is tweaked (e.g. a pinched neck nerve may cause a brief shock-like paresthesia toward the scalp). In the older a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-linked Recessive
''Main Article'': Sex linkage X-linked recessive inheritance is a mode of Mendelian inheritance, inheritance in which a mutation in a gene on the X chromosome causes the phenotype to be always expressed in males (who are necessarily hemizygous for the gene mutation because they have one X and one Y chromosome) and in females who are homozygous for the gene mutation (see zygosity). Females with one copy of the mutated gene are carriers. X-linked inheritance means that the gene causing the trait or the disorder is located on the X chromosome. Females have two X chromosomes while males have one X and one Y chromosome. Carrier females who have only one copy of the mutation do not usually express the phenotype, although differences in X-chromosome inactivation (known as skewed X-inactivation) can lead to varying degrees of clinical expression in carrier females, since some cells will express one X allele and some will express the other. The current estimate of sequenced X-linked genes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intellectual Disabilities
Intellectual disability (ID), also known as general learning disability (in the United Kingdom), and formerly mental retardation (in the United States), Rosa's Law, Pub. L. 111-256124 Stat. 2643(2010).Archive is a generalized neurodevelopmental disorder characterized by significant impairment in intellectual and adaptive functioning that is first apparent during childhood. Children with intellectual disabilities typically have an intelligence quotient (IQ) below 70 and deficits in at least two adaptive behaviors that affect everyday living. According to the DSM-5, intellectual functions include reasoning, problem solving, planning, abstract thinking, judgment, academic learning, and learning from experience. Deficits in these functions must be confirmed by clinical evaluation and individualized standard IQ testing. On the other hand, adaptive behaviors include the social, developmental, and practical skills people learn to perform tasks in their everyday lives. Deficits in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tendons
A tendon or sinew is a tough band of dense fibrous connective tissue that connects muscle to bone. It sends the mechanical forces of muscle contraction to the skeletal system, while withstanding tension. Tendons, like ligaments, are made of collagen. The difference is that ligaments connect bone to bone, while tendons connect muscle to bone. There are about 4,000 tendons in the adult human body. Structure A tendon is made of dense regular connective tissue, whose main cellular components are special fibroblasts called tendon cells (tenocytes). Tendon cells synthesize the tendon's extracellular matrix, which abounds with densely-packed collagen fibers. The collagen fibers run parallel to each other and are grouped into fascicles. Each fascicle is bound by an endotendineum, which is a delicate loose connective tissue containing thin collagen fibrils and elastic fibers. A set of fascicles is bound by an epitenon, which is a sheath of dense irregular connective tissue. The wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
