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Contractures
In pathology, a contracture is a permanent shortening of a muscle or joint. It is usually in response to prolonged hypertonia, hypertonic spasticity in a concentrated muscle area, such as is seen in the tightest muscles of people with conditions like spastic diplegia, spastic cerebral palsy, but can also be due to the congenital abnormal development of muscles and connective tissue in the womb. Contractures develop when normally elastic tissues such as muscles or tendons are replaced by inelastic tissues (fibrosis). This results in the shortening and hardening of these tissues, ultimately causing rigidity, joint deformities and a total loss of movement around the joint. Most of the physical therapy, occupational therapy and other exercise regimens targeted towards people with spasticity focuses on trying to prevent contractures from happening in the first place. However, research on sustained traction of connective tissue in approaches such as adaptive yoga has demonstrated that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthrogryposis
Arthrogryposis (AMC) describes congenital joint contracture in two or more areas of the body. It derives its name from Greek, literally meaning "curving of joints" (', "joint"; ', late Latin form of late Greek ', "hooking"). Children born with one or more joint contractures have abnormal fibrosis of the muscle tissue causing muscle shortening, and therefore are unable to perform active extension and flexion in the affected joint or joints. AMC has been divided into three groups: amyoplasia, distal arthrogryposis, and syndromic. Amyoplasia is characterized by severe joint contractures and muscle weakness. Distal arthrogryposis mainly involves the hands and feet. Types of arthrogryposis with a primary neurological or muscle disease belong to the syndromic group. Signs and symptoms Often, every joint in a patient with arthrogryposis is affected; in 84% all limbs are involved, in 11% only the legs, and in 4% only the arms are involved. Every joint in the body, when affected, displays ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscle Contracture
Muscle contractures can occur for many reasons, such as paralysis, muscular atrophy, and forms of muscular dystrophy. Fundamentally, the muscle and its tendons shorten, resulting in reduced flexibility. For example, in the case of partial paralysis (i.e. poliomyelitis) the loss of strength and muscle control tend to be greater in some muscles than in others, leading to an imbalance between the various muscle groups around specific joints. Case in point: when the muscles which dorsiflex (flex the foot upward) are less functional than the muscles which plantarflex (flex the foot downward) a contracture occurs, giving the foot a progressively downward angle and loss of flexibility. Various interventions can slow, stop, or even reverse muscle contractures, ranging from physical therapy to surgery. A common cause for having the ankle lose its flexibility in this manner is from having sheets tucked in at the foot of the bed when sleeping. The weight of the sheets keep the feet plantar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dupuytren's Contracture
Dupuytren's contracture (also called Dupuytren's disease, Morbus Dupuytren, Viking disease, palmar fibromatosis and Celtic hand) is a condition in which one or more fingers become progressively bent in a flexed position. It is named after Guillaume Dupuytren, who first described the underlying mechanism of action, followed by the first successful operation in 1831 and publication of the results in ''The Lancet'' in 1834. It usually begins as small, hard nodules just under the skin of the palm, then worsens over time until the fingers can no longer be fully straightened. While typically not painful, some aching or itching may be present. The ring finger followed by the little and middle fingers are most commonly affected. It can affect one or both hands. The condition can interfere with activities such as preparing food, writing, putting the hand in a tight pocket, putting on gloves, or shaking hands. The cause is unknown but might have a genetic component. Risk factors includ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marden–Walker Syndrome
Marden–Walker syndrome (MWS) is a rare autosomal recessive congenital disorder. It is characterized by blepharophimosis, microcephaly, micrognathia, multiple joint contractures, arachnodactyly, camptodactyly, kyphoscoliosis and delayed motor development and is often associated with cystic dysplastic kidneys, dextrocardia, Dandy–Walker malformation and agenesis of corpus callosum. Signs and symptoms Most of the signs of MWS are present during the neonatal period. The most common signs at this state are multiple congenital joint contractures, dysmorphic features with mask-like face, blepharophimosis, ptosis, micrognathia, cleft or high arched palate, low-set ears, arachnodactyly, chest deformation as pectus, kyphoscoliosis and absent deep tendon reflexes are frequent minor malformations have also been described and consist of renal anomalies, cardiovascular abnormalities, hypospadias, omphalomesenteric duct, hypertriphic pyloric stenosis, duodenal bands, hyoplastic right low ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spasticity
Spasticity () is a feature of altered skeletal muscle performance with a combination of paralysis, increased tendon reflex activity, and hypertonia. It is also colloquially referred to as an unusual "tightness", stiffness, or "pull" of muscles. Clinically, spasticity results from the loss of inhibition of motor neurons, causing excessive velocity-dependent muscle contraction. This ultimately leads to hyperreflexia, an exaggerated deep tendon reflex. Spasticity is often treated with the drug baclofen, which acts as an agonist at GABA receptors, which are inhibitory. Spastic cerebral palsy is the most common form of cerebral palsy, which is a group of permanent movement problems that do not get worse over time. GABA's inhibitory actions contribute to baclofen's efficacy as an anti-spasticity agent. Cause Spasticity mostly occurs in disorders of the central nervous system (CNS) affecting the upper motor neurons in the form of a lesion, such as spastic diplegia, or upper mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clubfoot
Clubfoot is a birth defect where one or both feet are rotated inward and downward. Congenital clubfoot is the most common congenital malformation of the foot with an incidence of 1 per 1000 births. In approximately 50% of cases, clubfoot affects both feet, but it can present unilaterally causing one leg or foot to be shorter than the other. Most of the time, it is not associated with other problems. Without appropriate treatment, the foot deformity will persist and lead to pain and impaired ability to walk, which can have a dramatic impact on the quality of life. The exact cause is usually not identified. Both genetic and environmental factors are believed to be involved. There are two main types of congenital clubfoot: idiopathic (80% of cases) and secondary clubfoot (20% of cases). The idiopathic congenital clubfoot is a multifactorial condition that includes environmental, vascular, positional, and genetic factors. There appears to be hereditary component for this birth d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freeman–Sheldon Syndrome
Freeman–Sheldon syndrome (FSS) is a very rare form of multiple congenital contracture (MCC) syndromes ( arthrogryposes) and is the most severe form of distal arthrogryposis (DA). It was originally described by Ernest Arthur Freeman and Joseph Harold Sheldon in 1938.James, William; Berger, Timothy; Elston, Dirk (2005). ''Andrews' Diseases of the Skin: Clinical Dermatology''. (10th ed.). Saunders. . As of 2007, only about 100 cases had been reported in medical literature. Signs and symptoms The symptoms of Freeman–Sheldon syndrome include drooping of the upper eyelids, strabismus, low-set ears, a long philtrum, gradual hearing loss, scoliosis and walking difficulties. Gastroesophageal reflux has been noted during infancy, but usually improves with age. The tongue may be small, and the limited movement of the soft palate may cause nasal speech. Often there is an H- or Y-shaped dimpling of the skin over the chin. Cause FSS is caused by genetic changes. Krakowiak et al. (1998) ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Burn Scar Contracture
Burn scar contracture is the tightening of the skin after a second or third degree burn. When skin is burned, the surrounding skin begins to pull together, resulting in a contracture. It needs to be treated as soon as possible because the scar A scar (or scar tissue) is an area of fibrous tissue that replaces normal skin after an injury. Scars result from the biological process of wound repair in the skin, as well as in other organs, and tissues of the body. Thus, scarring is a n ... can result in restriction of movement around the injured area. This is mediated by myofibroblasts. __TOC__ Diagnosis Treatment Burn scar contractures do not go away on their own, although may improve with the passage of time, with occupational therapy and physiotherapy, and with splinting. If persistent the person may need the contracture to be surgically released. Techniques may include local skin flaps (z-plasty) or skin grafting (full thickness or split thickness). There are also phar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscle Contraction
Muscle contraction is the activation of tension-generating sites within muscle cells. In physiology, muscle contraction does not necessarily mean muscle shortening because muscle tension can be produced without changes in muscle length, such as when holding something heavy in the same position. The termination of muscle contraction is followed by muscle relaxation, which is a return of the muscle fibers to their low tension-generating state. For the contractions to happen, the muscle cells must rely on the interaction of two types of filaments which are the thin and thick filaments. Thin filaments are two strands of actin coiled around each, and thick filaments consist of mostly elongated proteins called myosin. Together, these two filaments form myofibrils which are important organelles in the skeletal muscle system. Muscle contraction can also be described based on two variables: length and tension. A muscle contraction is described as isometric if the muscle tension changes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myofibroblast
A myofibroblast is a cell phenotype that was first described as being in a state between a fibroblast and a smooth muscle cell. Structure Myofibroblasts are contractile web-like fusiform cells that are identifiable by their expression of α-smooth muscle actin within their cytoplasmic stress fibers. In the gastrointestinal and genitourinary tracts, myofibroblasts are found subepithelially in mucosal surfaces. Here they not only act as a regulator of the shape of the crypts and villi, but also act as stem-niche cells in the intestinal crypts and as parts of atypical antigen-presenting cells. They have both support as well as paracrine function in most places. Location Myofibroblasts were first identified in granulation tissue during skin wound healing. Typically, these cells are found in granulation tissue, scar tissue (fibrosis) and the stroma of tumours. They also line the gastrointestinal tract, wherein they regulate the shapes of crypts and villi. Markers Myofibroblasts ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Capsular Contracture
Capsular contracture is a response of the immune system to foreign materials in the human body. Medically, it occurs mostly in context of the complications from breast implants and artificial joint prosthetics. The occurrence of capsular contraction follows the formation of capsules of tightly-woven collagen fibers, created by the immune response to the presence of foreign objects surgically installed to the human body, e.g. breast implants, artificial pacemakers, orthopedic prostheses; biological protection by isolation and toleration. Capsular contracture occurs when the collagen-fiber capsule shrinks, tightens and compresses the breast implant, much like the collapse of a bubble gum bubble.Dr. Ted Eisenberg and Joyce K. Eisenberg, ‘’The Scoop on Breasts: A Plastic Surgeon Busts the Myths,’’ Incompra Press, 2012, It is a medical complication that can be painful and discomforting, and might distort the aesthetics of the breast implant and the breast. Although the cau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Matrix Metalloproteinase
Matrix metalloproteinases (MMPs), also known as matrix metallopeptidases or matrixins, are metalloproteinases that are calcium-dependent zinc-containing endopeptidases; other family members are adamalysins, serralysins, and astacins. The MMPs belong to a larger family of proteases known as the metzincin superfamily. Collectively, these enzymes are capable of degrading all kinds of extracellular matrix proteins, but also can process a number of bioactive molecules. They are known to be involved in the cleavage of cell surface receptors, the release of apoptotic ligands (such as the FAS ligand), and chemokine/cytokine inactivation. MMPs are also thought to play a major role in cell behaviors such as cell proliferation, migration (adhesion/dispersion), differentiation, angiogenesis, apoptosis, and host defense. They were first described in vertebrates (1962), including humans, but have since been found in invertebrates and plants. They are distinguished from other endopeptidase ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
