Atrophy is the wasting of tissue, muscle or nerve cells. It is a symptom of many medical conditions. Atrophy most often occurs in the muscles, although it can also occur in the brain, organs, mucous membranes (moist lining of body passageways) and nerves. People who have atrophy may also experience dementia, seizures, paralysis and aphasia (loss of language skills).

Atrophy can be caused by various factors such as:

• Disease (e.g., muscular dystrophy, polio)
• Age
• Injury
• Lack of exercise

Treatment of muscular atrophy often relies on physical therapy to rebuild the muscle mass. Brain atrophy (cerebral atrophy) may recover on its own as the brain cells regenerate. However, the damage caused by brain atrophy may be permanent.

Atrophy is a symptom of many medical conditions. It causes the wasting of tissue, muscle or nerve cells. In healthy bodies, cells die and are replaced at a constant rate. Atrophy occurs when cells begin to die without being replaced. Eventually, the associated tissue begins to shrink and lose its ability to function effectively.

Atrophy can occur anywhere in the body, although the most common types of atrophy affect the muscles and the brain (cerebral atrophy). Muscular atrophy can be caused by diseases (e.g. muscular dystrophy, Lou Gehrig’s disease), malnutrition or simple lack of muscle use. Muscular atrophy is particularly common following the injury of a part of the body that is usually active (e.g. an arm or a leg). When the body part remains inactive, the muscles begin to waste. Muscular atrophy is also common in older people who are not active, where it leads to frailty and an increased risk of falls.

Cerebral atrophy is a symptom that accompanies many diseases and injuries of the brain. It occurs following the loss of brain neurons (nerve cells) and their connections, which are essential for most aspects of thought and action. Atrophy can also occur in other areas of the body (e.g. optical atrophy, vaginal atrophy, breast atrophy) and in mucous membranes, the moist lining of passageways in the body (e.g., mouth, nose, eyes and intestines).

Atrophy can range from mild to severe. For example, people with mild muscle atrophy may barely notice a difference in strength, although they may find it more difficult to perform certain tasks such as carrying heavy items or climbing stairs. Severe atrophy, on the other hand, can affect many aspects of a person’s life. Severe brain atrophy, for example, may cause dementia, paralysis or even result in coma.

Depending on the underlying cause, other symptoms may be associated with atrophy, such as:

• Dementia. A decline in mental function that may interfere with the ability to perform daily functions. Dementia is not a disease. Instead it is the name given to a collection of symptoms that generally occur together and may be caused by certain medical conditions. These symptoms include memory loss, behavioral changes and problems with language. Atrophy to certain parts of the brain, particularly the frontal and temporal lobes, may cause dementia.
  
  
• Paralysis. The loss of movement in one or more body parts. It may be a symptom of a disease of or injury to the nerves, muscles, brain or spine. In some cases, paralysis is also accompanied by the loss of sensation in the affected area. Atrophy of the brain, spinal cord, nerves or muscles may lead to paralysis.
  
  
• Seizures. A sudden change in behavior or consciousness caused by abnormal brain activity. Seizures occur when neurons in the brain suddenly increase activity, causing an electrical storm that can overwhelm the brain. This can result in various symptoms depending on the area of the brain affected. These symptoms range from slight changes in taste or smell to loss of consciousness and involuntary muscle contractions that affect the whole body.
  

  

• Aphasia. A loss of the ability to use and understand language. It is the result of damage to the part of the brain that is associated with language, which, for most people, is the left side of the brain. Some people describe aphasia as being similar to visiting a foreign country and being surrounded by people speaking a language that is not understood.

There are many factors that can cause atrophy. Some potential causes include:

• Disease. Numerous diseases can cause atrophy of the brain (cerebral atrophy), muscles and other parts of the body. Examples of diseases that may cause atrophy include:
  
  
• • Muscular dystrophy
    
    
  • Multiple system atrophy
    
    
  • Osteoarthritis
    
    
  • Amyotrophic lateral sclerosis (ALS or Lou Gehrig's disease)
    
    
  • Guillain-Barré syndrome
    
    
  • Polio
    
    
  • Alzheimer's disease
    

    

  • Cerebral palsy
    
    
  • Stroke
    

    

  • AIDS (acquired immunodeficiency syndrome)
    
    
  • Multiple sclerosis
    

    

  • Myopathy
    
    
  • Neuropathy
    
    
  • Epilepsy
    
    
• Age. As the body ages, a certain amount of muscle atrophy naturally occurs. This is sometimes called sarcopenia. In addition to natural muscle loss, muscle atrophy in elderly people can also be due to malnutrition, lengthy immobilization and inactivity. Older people are also more susceptible to conditions that can cause atrophy, such as Alzheimer's disease, osteoarthritis and stroke.
  
  
• Injury. Muscle atrophy is common following an injury, especially injury to a part of the body that is usually active, such as an arm or a leg. As the body part remains inactive, the muscles begin to waste. Most people with injuries that inhibit movement of a certain body part require physical therapy to rebuild the muscle mass. A spinal cord injury can also result in atrophy and paralysis. Additionally, a head injury may cause cerebral atrophy.
  
  
• Lack of exercise. People who do not use their muscles on a regular basis increase their risk of developing muscle atrophy. This may be difficult to recognize, especially in people who are obese and who may not show distinct muscle definition.

Many cases of muscular atrophy can be treated and reversed with physical therapy.

In mild cases of atrophy, this usually involves the adoption of an exercise routine. Severe cases of atrophy may require professional attention. Physical therapists use exercises designed to slowly build muscle mass without incurring further injury.

Cerebral atrophy may not be as easily reversible, although, in some cases, brain cells may regenerate over time. The amount of recovery from cerebral atrophy depends on the location and severity of the atrophy. Sometimes, treating the underlying condition may slow or stop the atrophy.    

Some types of atrophy can be prevented by remaining active and engaging in a regular exercise routine. It may be difficult to prevent atrophy that is caused by disease or injury.

Preparing questions in advance can help patients have more meaningful discussions with healthcare providers regarding their condition. Patients may wish to ask their doctor the following questions related to atrophy:

1. Do I have atrophy?
   
   
2. How severe is my atrophy?
   
   
3. What can I do to prevent atrophy?
   
   
4. What has caused my atrophy?
   
   
5. What will be the effect of my atrophy?
   
   
6. Is there anything I will not be able to do because of my atrophy?
   
   
7. How will you treat my atrophy?
   
   
8. How do I stop my atrophy from getting worse?
   
   
9. Can you recommend a physical therapist?
   
   
10. How soon after my injury/disease should I start physical therapy?