Hypertonia is a term sometimes used synonymously with spasticity and rigidity in the literature surrounding damage to the central nervous system, namely upper motor neuron lesions. Impaired ability of damaged motor neurons to regulate descending pathways gives rise to disordered spinal reflexes, increased excitability of muscle spindles, and decreased synaptic inhibition. These consequences result in abnormally increased muscle tone of symptomatic muscles. Some authors suggest that the current definition for spasticity, the velocity-dependent over-activity of the stretch reflex, is not sufficient as it fails to take into account patients exhibiting increased muscle tone in the absence of stretch reflex over-activity. They instead suggest that "reversible hypertonia" is more appropriate and represents a treatable condition that is responsive to various therapy modalities like drug and/or physical therapy.
Symptoms associated with central nervous systems disorders are classified into positive and negative categories. Positive symptoms include those that increase muscle activity through hyper-excitability of the stretch reflex (i.e., rigidity and spasticity) where negative symptoms include those of insufficient muscle activity (i.e. weakness) and reduced motor function. Often the two classifications are thought to be separate entities of a disorder; however, some authors propose that they may be closely related.
Hypertonia is caused by upper motor neuron lesions which may result from injury, disease, or conditions that involve damage to the central nervous system. The lack of or decrease in upper motor neuron function leads to loss of inhibition with resultant hyperactivity of lower motor neurons. Different patterns of muscle weakness or hyperactivity can occur based on the location of the lesion, causing a multitude of neurological symptoms, including spasticity, rigidity, or dystonia.
Spastic hypertonia involves uncontrollable muscle spasms, stiffening or straightening out of muscles, shock-like contractions of all or part of a group of muscles, and abnormal muscle tone. It is seen in disorders such as cerebral palsy, stroke, and spinal cord injury. Rigidity is a severe state of hypertonia where muscle resistance occurs throughout the entire range of motion of the affected joint independent of velocity. It is frequently associated with lesions of the basal ganglia. Individuals with rigidity present with stiffness, decreased range of motion and loss of motor control. Dystonic hypertonia refers to muscle resistance to passive stretching (in which a therapist gently stretches the inactive contracted muscle to a comfortable length at very low speeds of movement) and a tendency of a limb to return to a fixed involuntary (and sometimes abnormal) posture following movement.
Therapeutic interventions are best individualized to particular patients.
Basic principles of treatment for hypertonia are to avoid noxious stimuli and provide frequent range of motion exercise.
Physiotherapy has been shown to be effective in controlling hypertonia through the use of stretching aimed to reduce motor neuron excitability. The aim of a physical therapy session could be to inhibit excessive tone as far as possible, give the patient a sensation of normal position and movement, and to facilitate normal movement patterns. While static stretch has been the classical means to increase range of motion, PNF stretching has been used in many clinical settings to effectively reduce muscle spasticity.
Icing and other topical anesthetics may decrease the reflexive activity for short period of time in order to facilitate motor function. Inhibitory pressure (applying firm pressure over muscle tendon) and promoting body heat retention and rhythmic rotation (slow repeated rotation of affected body part to stimulate relaxation) have also been proposed as potential methods to decrease hypertonia. Aside from static stretch casting, splinting techniques are extremely valuable to extend joint range of motion lost to hypertonicity. A more unconventional method for limiting tone is to deploy quick repeated passive movements to an involved joint in cyclical fashion; this has also been demonstrated to show results on persons without physical disabilities. For a more permanent state of improvement, exercise and patient education is imperative. Isokinetic, aerobic, and strength training exercises should be performed as prescribed by a physiotherapist, and stressful situations that may cause increased tone should be minimized or avoided.
Baclofen, diazepam and dantrolene remain the three most commonly used pharmacologic agents in the treatment of spastic hypertonia. Baclofen is generally the drug of choice for spinal cord types of spasticity, while sodium dantrolene is the only agent which acts directly on muscle tissue. Tizanidine is also available. Phenytoin with chlorpromazine may be potentially useful if sedation does not limit their use. Ketazolam, not yet available in the United States, may be a significant addition to the pharmacologic set of options. Intrathecal administration of antispastic medications allows for high concentrations of drug near the site of action, which limits side effects.
6-Pyruvoyltetrahydropterin synthase deficiency is an autosomal recessive disorder that causes malignant hyperphenylalaninemia due to tetrahydrobiopterin deficiency.
It belongs to the rare diseases. It is a recessive disorder that is accompanied by hyperphenylalaninemia. Commonly reported symptoms are initial truncal hypotonia, subsequent appendicular hypertonia, bradykinesia, cogwheel rigidity, generalized dystonia, and marked diurnal fluctuation. Other reported clinical features include difficulty in swallowing, oculogyric crises, somnolence, irritability, hyperthermia, and seizures. Chorea, athetosis, hypersalivation, rash with eczema, and sudden death have also been reported. Patients with mild phenotypes may deteriorate if given folate antagonists such as methotrexate, which can interfere with a salvage pathway through which dihydrobiopterin is converted into tetrahydrobiopterin via dihydrofolate reductase. Treatment options include substitution with neurotransmitter precursors (levodopa, 5-hydroxytryptophan), monoamine oxidase inhibitors, and tetrahydrobiopterin. Response to treatment is variable and the long-term and functional outcome is unknown. To provide a basis for improving the understanding of the epidemiology, genotype/phenotype correlation and outcome of these diseases their impact on the quality of life of patients, and for evaluating diagnostic and therapeutic strategies a patient registry was established by the noncommercial International Working Group on Neurotransmitter Related Disorders (iNTD).Chlorophenoxy herbicide
Chlorophenoxy herbicides are a class of herbicide which includes: MCPA, 2,4-D, 2,4,5-T and mecoprop. Large amounts have been produced since the 1950s for agriculture. Acute toxic effects after oral consumption are varied and may include: vomiting, abdominal pain, diarrhoea, gastrointestinal haemorrhage acutely followed by coma, hypertonia, hyperreflexia, ataxia, nystagmus, miosis, hallucinations and convulsions. Treatment with urinary alkalinization may be helpful but evidence to support this practice is limited.Eperisone
Eperisone (formulated as the eperisone hydrochloride salt) is an antispasmodic drug.
Eperisone acts by relaxing both skeletal muscles and vascular smooth muscles, and demonstrates a variety of effects such as reduction of myotonia, improvement of circulation, and suppression of the pain reflex. The drug inhibits the vicious circle of myotonia by decreasing pain, ischaemia, and hypertonia in skeletal muscles, thus alleviating stiffness and spasticity, and facilitating muscle movementEperisone also improves dizziness and tinnitus associated with cerebrovascular disorders or cervical spondylosis.
Eperisone has a relatively low incidence of sedation when compared with other antispasmodic drugs; this simplifies the clinical application of the drug and makes it an attractive choice for patients who require antispasmodic therapy without a reduction in alertness.
Eperisone also facilitates voluntary movement of the upper and lower extremities without reducing muscle power; it is therefore useful during the initial stage of rehabilitation and as a supporting drug during subsequent rehabilitative therapy.Hyperekplexia
Hyperekplexia ("exaggerated surprise") is a neurologic disorder classically characterised by pronounced startle responses to tactile or acoustic stimuli and hypertonia. The hypertonia may be predominantly truncal, attenuated during sleep and less prominent after a year of age. Classic hyperekplexia is caused by genetic mutations in a number of different genes, all of which play an important role in glycine neurotransmission. Glycine is used by the central nervous system as an inhibitory neurotransmitter. Hyperekplexia is generally classified as a genetic disease, but some disorders can mimic the exaggerated startle of hyperekplexia.Lower motor neuron lesion
A lower motor neuron lesion is a lesion which affects nerve fibers traveling from the ventral horn or anterior grey column of the spinal cord to the relevant muscle(s) – the lower motor neuron.One major characteristic used to identify a lower motor neuron lesion is flaccid paralysis – paralysis accompanied by loss of muscle tone. This is in contrast to an upper motor neuron lesion, which often presents with spastic paralysis – paralysis accompanied by severe hypertonia.Momin Prohod
Momin Prohod (Bulgarian: Момин проход) is located in western Bulgaria and is part of the Kostenets Municipality in the Sofia Province, about 70 km (43 mi) from city of Sofia. In 2006 it obtained administrative autonomy and the status of town (град).
It is a health resort and spa in southwest part of Sredna Gora mountain. The resort is an important therapeutic and rehabilitation centre for several diseases. The water of Momin Prohod is second to that of the Narechenski Bani spa in its radioactivity. Third in Europe, and 25th in the world.Its fame owes to the achievements of the local specialists in the healing of diseases of the respiratory, the cardiovascular, the nervous and the digestive systems, of metabolic and different kinds of allergic conditions.Specialists have provided the favourable influence of the rich in radon mineral waters on diseases of the cardiovascular system. What is more, some ten years ago, they developed and presently successfully apply a methodology for the treatment of pulmonary diseases and hypertonia, including a complex of taking mineral vane, inhalation and negative ionization in rooms specially equipped for that purpose. For years on end curement of post poliomyelitis conditions of children is practised here.The treatment with rich in radon mineral waters accelerates the reporative and regenerative processes and influences the antiseptic processes and conditions of aggravation of the peripheral nervous system. The rich in radon mineral water of Momin Prohod is successfully applied for the treatment of skin diseases, light forms of diabetes, obesity and joint disturbance. Some recent investigations proved the prognosis of the scientists about the favourable influence of the water on the immune reactivity of human organism and its strengthened resistance to ray injuries.Monosomy 9p
Monosomy 9p (also known as Alfi's Syndrome or simply 9P-) is a rare chromosomal disorder in which there is deletion (monosomy) of a portion of chromosome 9. Symptoms include microgenitalia, intellectual disability with microcephaly and dysmorphic features.
The location has recently been narrowed to 9p22.2-p23.Various clinical features have been associated with this disease including trigonocephaly, flattened occiput, prominent forehead, broad flat nasal bridge, anteverted nares, malformed external ears, hypertelorism, and hypertonia.Muscle tone
In physiology, medicine, and anatomy, muscle tone (residual muscle tension or tonus) is the continuous and passive partial contraction of the muscles, or the muscle's resistance to passive stretch during resting state. It helps to maintain posture and declines during REM sleep.Paralympic Games
The Paralympics is a very major international multi-sport event involving athletes with a range of disabilities, including impaired muscle power (e.g. paraplegia and quadriplegia, muscular dystrophy, post-polio syndrome, spina bifida), impaired passive range of movement, limb deficiency (e.g. amputation or dysmelia), leg length difference, short stature, hypertonia, ataxia, athetosis, vision impairment and intellectual impairment. There are Winter and Summer Paralympic Games, which since the 1988 Summer Games in Seoul, South Korea, are held almost immediately following the respective Olympic Games. All Paralympic Games are governed by the International Paralympic Committee (IPC).
The Paralympics has grown from a small gathering of British World War II veterans in 1948 to become one of the largest international sporting events by the early 21st century. The Paralympics has grown from 400 athletes with a disability from 23 countries in 1960 to thousands of competitors from over 100 countries in the London 2012 Games. Paralympians strive for equal treatment with non-disabled Olympic athletes, but there is a large funding gap between Olympic and Paralympic athletes.
The Paralympic Games are organized in parallel with the Olympic Games, while the IOC-recognized Special Olympics World Games include athletes with intellectual disabilities, and the Deaflympics include deaf athletes.Given the wide variety of disabilities that Paralympic athletes have, there are several categories in which the athletes compete. The allowable disabilities are broken down into ten eligible impairment types. The categories are impaired muscle power, impaired passive range of movement, limb deficiency, leg length difference, short stature, hypertonia, ataxia, athetosis, vision impairment and intellectual impairment. These categories are further broken down into classifications, which vary from sport to sport.Paratriathlon
Paratriathlon is a variant of the triathlon for athletes with a physical disability. The sport is governed by the International Triathlon Union (ITU), and was first held as a Paralympic event at the 2016 Summer Paralympics in Rio de Janeiro, Brazil.The annual ITU Triathlon World Championships includes a paratriathlon sprint distance event with a 750 m swim, 20 km cycling using handcycles, bicycles or tandem bicycles with a guide and a 5 km wheelchair or running race. Athletes compete in six categories according to the nature of their physical impairments, with variations made to the traditional event structure commensurate with their disability.Paratriathlon at the Summer Paralympics will be a sprint race consisting of 750 m swimming, 20 km cycling and 5 km running stages.At the 2018 Commonwealth Games, paratriathlon was staged with athletes across multiple categories, with staggered starts introduced to ensure fair competition between categories.Paratriathlon classification
Paratriathlon classification is the classification system for athletes participating in paratriathlon. It is governed by the International Triathlon Union (ITU) The sport has been included in the 2016 Summer Paralympics.Spastic quadriplegia
Spastic quadriplegia, also known as spastic tetraplegia, is a subset of spastic cerebral palsy that affects all four limbs (both arms and legs).
Compared to quadriplegia, spastic tetraplegia is defined by spasticity of the limbs as opposed to strict paralysis. It is distinguishable from other forms of cerebral palsy in that those afflicted with the condition display stiff, jerky movements stemming from hypertonia of the muscles.Spastic quadriplegia, while affecting all four limbs more or less equally, can still present parts of the body as stiffer than others, such as one arm being tighter than another arm, and so forth. Spastic triplegia, meanwhile, involves three limbs (such as one arm and two legs, or one leg and two arms, etc.); spastic diplegia affects two limbs (commonly just the legs), spastic hemiplegia affects one or another entire side of the body (left or right); and spastic monoplegia involves a single limb.Spasticity
Spasticity (from Greek, Modern spasmos-, meaning 'drawing, pulling') 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.T32 (classification)
T32 is disability sport classification for track events in disability athletics. This is a wheelchair racing class. The classification is one of three classes of wheelchair racing for people with athetosis, ataxia or hypertonia. The number of events available to people in this class has decreased since the 1980s, with no T32 events at the 2016 Summer Paralympics. While undergoing classification, T32 competitors both undergo a bench test of muscle coordination and demonstrate their skills in athletics.T34 (classification)
T34 is a disability sport classification for disability athletics. The classification is one of eight specifically for athletes with cerebral palsy, and one of four for athletes with cerebral palsy who use a wheelchair. People in this class have hypertonia, ataxia and athetosis. This class includes people who have cerebral palsy, or who have had a stroke or traumatic brain injury.T35 (classification)
T35 (T for track) is a disability sport classification for disability athletics' running competitions. It includes people who have coordination impairments such as hypertonia, ataxia and athetosis. This includes people with cerebral palsy. The classification is used at the Paralympic Games. The corresponding F35 classification (F for (in)Field) includes club and discus throw, shot put, and javelin.T36 (classification)
T36 is a disability sport classification for disability athletics. It includes people who have coordination impairments such as hypertonia, ataxia and athetosis. It includes people with cerebral palsy. T36 is used by the International Paralympic Committee. This classification competes at the Paralympic Games.T37 (classification)
T37 is a disability sport classification for disability athletics in track and jump events. It includes people who have coordination impairments such as hypertonia, ataxia and athetosis. It is the athletics equivalent of the more general CP7 classification.T38 (classification)
T38 and CP8 are disability sport classification for disability athletics intended for people with cerebral palsy. It includes people who have coordination impairments such as hypertonia, ataxia and athetosis. Runners in this class may appear to have a slight limp when they are running but otherwise have a stride similar to able-bodied runners. Events for this class include 100 meters, 400 meters, 1,500 meters, and the long jump.