Hypertonia is a condition where there is too much muscle tone, so that the arms or legs, for example, are stiff and difficult to move. Muscle tone is regulated by signals that go from the brain to the nerves telling the muscle to contract. Hypertonia occurs when the areas of the brain or spinal cord that control these signals are damaged. This can occur for many reasons, such as a blow to the head, stroke, brain tumors, toxins that affect the brain, neurodegenerative processes, such as in multiple sclerosis or Parkinson’s disease, or neurodevelopmental abnormalities, such as in cerebral palsy. Hypertonia often limits how easily the joints can move. If it affects the legs, walking can become stiff and people can fall because it is difficult for the body to react quickly enough to regain balance. If the hypertension is severe, it can cause a joint to become “frozen,” which doctors call a joint contracture. Spasticity is a term often used interchangeably with hypertonia. However, spasticity is a special type of hypertonia, where muscle spasms increase with movement. In this type, patients usually have exaggerated reflex reactions. Rigidity is another type of hypertonia, where the muscles have the same amount of stiffness regardless of the degree of movement. Rigidity usually occurs in diseases such as Parkinson’s disease that involve the basal ganglia (a deep region of the brain). To distinguish between these types of hypertension, a doctor will relax the patient and then move the arm or leg at different speeds and in a variety of directions.
Treatment
Muscle relaxant drugs such as baclofen, diazepam, and dantrolene may be prescribed to reduce spasticity. All of these drugs can be taken by mouth, but baclofen can also be injected directly into the cerebrospinal fluid through an implanted pump. Botulinum toxin is often used to relieve hypertension in a specific area of the body because its effects are local, not whole-body. People with hypertension should try to maintain as much movement as possible by exercising within their limits and using physical therapy. Drugs that affect the dopamine system (dopamine is a brain chemical), such as levodopa/carbidopa or entacapone, are often used to treat the stiffness associated with Parkinson’s disease.
Prognosis
The prognosis depends on the severity of the hypertension and its cause. In some cases, such as cerebral palsy, the hypertension may not change over a lifetime. in other cases, the hypertension may worsen along with the underlying disease. If the hypertension is mild, it has little or no effect on a person’s health. If there is moderate hypertension, falls or joint contractures can affect a person’s health and safety. If the hypertension is severe enough to cause immobility, potential consequences include increased fragility and fracture, infection, bedsores, and pneumonia.
Research
NINDS supports research into brain and spinal cord disorders that can cause hypertension. The goal of this research is to learn more about how the nervous system adapts after injury or disease and to find ways to prevent and treat these disorders.
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investigations
performed on this condition.
Organizations
Dystonia Medical Research Foundation
Non-profit medical research foundation that funds research, promotes awareness, and provides education and support about dystonia, a movement disorder.
1 East Wacker Drive
Suite 2810
Chicago, IL 60601-1905
[email protected]
http://www.dystonia-foundation.org
Phone: Chicago
Fax: 312-803-0138
Christopher and Dana Reeve Foundation
The Reeve Foundation is dedicated to curing spinal cord injury by funding innovative research and improving the quality of life for people living with paralysis through grants, information and advocacy.
636 Morris Turnpike
Suite 3A
Short Hills, NJ 07078
[email protected]
http://www.christopherreeve.org
Tel: Short Hills
Fax: 973-912-9433
Cerebral Palsy Foundation
Dedicated to funding research and educational activities relevant to discovering the cause, cure and evidence-based care for people with CP and related developmental disabilities.
3 Columbus Circle, 15th floor
New York, NY 10019
[email protected]
http://yourcpf.org
Phone: New York
Fax: 917-599-0431
