Muscle atrophy, or disuse atrophy, is defined as a decrease in the mass of the muscle; it can be a partial or complete wasting away of muscle.

When a muscle atrophies, this leads to muscle weakness
Muscle atrophy results from a co-morbidity of several common diseases, including cancer, AIDS ,congestive heart failure, COPD( Chronic obstructive pulmonary disease), Renal failure and severe burns; patients who have “cachexia “ in these disease settings have a poor prognosis. Moreover, starvation eventually leads to muscle atrophy. Disuse of the muscles will also lead to atrophy.

CAUSES

Muscle atrophy, or muscle wasting, results from loss of muscle tissue.

Little or no physical exercise and a sedentary lifestyle are common causes of muscle atrophy, in this case called disuse atrophy.

Other common causes of disuse atrophy include medical conditions that decrease mobility, such as rheumatoid arthritis (chronic autoimmune disease characterized by joint inflammation)or osteoarthritis (thinning and weakening of the bones), and injuries, such as broken bones and burns.

The aging process often leads to slow but progressive muscle atrophy.

Common causes include neuromuscular diseases, such as spinal cord atrophy, multiple sclerosis (disease that affects the brain and spinal cord causing weakness, coordination, balance difficulties, and other problems),

Amyotrophic lateral sclerosis (ALS, also known as Lou Gehrig’s disease; a severe neuromuscular disease that causes muscle weakness and disability), or Guillain-Barre syndrome (autoimmune nerve disorder).

Diabetic neuropathy, nerve damage associated with diabetes, may also lead to atrophy of the muscles.

In some cases, muscle atrophy can be a symptom of serious malnutrition or alcohol-related muscle disease.

Injuries or trauma to nerves due to spinal cord injury, burns or stroke can also lead to muscle atrophy. Depending on the cause, atrophy may occur in one muscle, a group of muscles, or the entire body and it may be accompanied by numbness, pain or swelling, as well as other types of neuromuscular or skin symptoms.

SIGNS AND SYMPTOMS
Muscle atrophy may accompany other symptoms that vary depending on the underlying disease, disorder or condition. Symptoms that frequently affect the muscles may also involve other body systems.

Muscle atrophy may accompany other symptoms affecting the neuromuscular system including:

• Balance problems, difficulty walking, and falls
• Facial weakness
• Gradual difficulty walking and speaking, memory loss, tingling or weakness of extremities
• Impaired balance and coordination
• Loss of muscle coordination
• Numbness or tingling in arms or legs
• Progressive loss of movement
• Progressive weakness and numbness in the legs
• Symptoms of multiple sclerosis, such as weakness, numbness or tingling, vision problems, unsteady walk, fatigue, and depression.

Muscle atrophy may accompany symptoms related to other body systems and conditions including:

• Fatigue and general ill feeling
• General stiffness that lasts more than one hour after rising in the morning
• Swelling of an injured area

Serious symptoms that might indicate a life-threatening condition
In some cases, muscle atrophy can be life threatening. Some indications are:

• Change in level of consciousness or alertness, such as passing out or unresponsiveness
• Garbled or slurred speech or inability to speak
• Paralysis or inability to move a body part
• Sudden change in vision, loss of vision, or eye pain
• Sudden weakness of numbness on one side of the body
• Worst headache of your life