According to MedlinePlus, deltoid muscle atrophy is a condition in which the deltoid muscles of the shoulder have become wasted or diminished, resulting in loss of strength or movement. Causes of deltoid muscle atrophy include aging, injury, disuse, nerve dysfunction, muscular dystrophy or cachexia, a wasting syndrome.
The deltoids are the muscles that form the rounded part of the shoulders. These are the primary muscles that enable the shoulders to move. The two main types of deltoid muscle atrophy are disuse and neurogenic atrophy.
A lack of physical activity brings on disuse atrophy. Those with sedentary jobs are prone to muscle atrophy, as are those with movement-inhibiting medical conditions. Astronauts lose muscle tone because of the lack of gravity in the weightless environment of space. Atrophy brought on by disuse of the deltoid muscles can usually be cured by a supervised exercise program.
Neurogenic atrophy, which involves injury or disease in the nerves connected to the muscles, is far more serious. Causes of neurogenic atrophy include spinal cord injuries, strokes, burns, diabetic neuropathy, herniated discs, osteoarthritis, carpal tunnel and Lou Gehrig's disease. If someone has sudden, unexplained or long-term deltoid muscle atrophy, a health care provider should be contacted. Tests to determine the cause of the atrophy might involve X-rays, CT scans, electromyography, MRI scans or nerve conduction studies. Treatments often include physical therapy, ultrasound therapy or surgery.