Disuse atrophy can be caused by immobility, such as an arm being in a cast for a long period of time. It can also occur to some degree if a person stops their usual activities, such as walking.
What Causes Disuse Atrophy?
There are many reasons that a person may stop using a specific muscle group or many muscles of the body.
Disuse atrophy can affect specific areas of the body, such as the arm muscles while a broken bone in the arm is healing. And sometimes disuse atrophy is more generalized, such as after a period of bed rest while recovering from a major surgical procedure, Often, a lack of muscle use due to weakness causes the muscle to weaken further.
Disuse atrophy affecting a limited area of the body can occur due to:
Lack of mobility due to a cast while recovering from an injury A nerve injury that causes weakness of a muscle Nerve damage from drugs, such as chemotherapy Weakness of an area of the body due to a stroke, brain tumor, head trauma, or spine disease Joint disease that limits mobility Joint pain A neuropathic pain condition, which can cause a person to avoid using a specific muscle group
Generalized disuse atrophy can develop from becoming bedridden for a prolonged period of time due to illness. Sometimes, having a sedentary lifestyle can lead to disuse atrophy as well.
Prevention
Disuse atrophy can be prevented with muscle movement. This can be extremely difficult if you have severe pain, if the muscle is weakened by neurological disease, or if you are bedridden or unable to voluntarily move for any other reason.
Often, physical therapy is used to help prevent disuse atrophy when there is a risk. For example, you might be scheduled for physical therapy within days of surgery.
And sometimes passive therapy or another type of manual therapy is started even before you can actively participate. Your therapist might move your muscles for you to help prevent stiffness, pain, and contractures that would make it harder for you to voluntarily move once you are able to do so.
Other strategies may include electrical stimulation or injections to alleviate problems that can contribute to disuse atrophy.
Treatment
Disuse atrophy can be a temporary condition if the unused muscles are exercised properly after a limb is taken out of a cast or a person has regained enough strength to exercise after being bedridden for a period of time.
Doctors recommend that patients who have disuse atrophy complete various exercises that involve the muscle, usually on a daily basis.
A Word From Verywell
Disuse atrophy is not uncommon. You might have noticed thinning of muscles after you or someone else has had cast removed or after stitches have healed. In these situations, the muscle may grow and strengthen again even without any medical intervention. When disuse atrophy is severe, or if the muscles are so weakened that it is difficult to start using them again, a progressive therapy program can gradually help rebuild full or partial muscle strength. And if you are at risk of disuse atrophy, it can be more effective to use preventative strategies than to work on rehabilitation after atrophy has occurred.