Muscle atrophy is a condition in which the skeletal muscles shrink in size and the muscle fibers become smaller and thinner or even disappear due to muscle dystrophy, which triggers a weakening of muscle strength that affects people’s lives and health. In the early stages of muscle atrophy, the facial muscles show symptoms and the eyes cannot be closed. The muscles of both cheeks are dystrophic, and the patient is unable to puff the cheeks, chewing is impaired, and swallowing is difficult. This may be accompanied by hypesthesia and a weakened corneal reflex. Continuing downward, there is difficulty lifting both upper extremities and the scapulae protrude. There is a progressive decrease in muscle strength grade. In severe cases, muscle strength reaches grade 0, with complete paralysis of the whole body and with the risk of medullary paralysis, which can endanger the life of the patient. However, the symptoms of muscle atrophy can be relieved by proper treatment, so we should detect and treat it as early as possible. Muscle atrophy can cause a decrease in skeletal muscle volume. Patients can understand their situation by measuring muscle circumference, but a decrease in muscle circumference is not absolute muscle atrophy; it may also be due to insufficient exercise over time. All in all, when muscle circumference decreases and is accompanied by these early symptoms, people should be alert and go to the hospital as soon as possible for examination.