Spastic vs. Flaccid Paralysis: Understanding & Treating Loss of Muscle Function

Paralysis is a complex condition. It affects each person differently and presents distinct challenges depending on its cause and what areas of the body are impacted. However, when discussing how the muscles react to nerve damage, there are two different categories: spastic paralysis and flaccid paralysis. We’ll explain how these two categories differ, how they affect the body, and what treatments are available for both. 

Spastic vs. Flaccid Paralysis

The spastic and flaccid terms refer to how the muscles act when they’re paralyzed—any type of paralysis can be either spastic or flaccid. In some cases, it can be both. It has been commonly observed that patients recovering from a stroke may have spastic paralysis in their legs while they have flaccidity in their arms. This can even change over the course of recovery. 

Spastic and flaccid paralysis impact the body in different ways, but they also share some similarities. For example, both spastic and flaccid paralysis causes muscle weakness, reduced coordination, and lack of motor control. However, because of their differences, treatments for them may vary. Various conditions and injuries can cause these forms of paralysis to occur, including stroke, spinal cord injury, and autoimmune diseases such as Multiple Sclerosis.

What Is Spastic Paralysis?

Spastic paralysis occurs when the neurons controlling muscle and motor function are damaged, and the ability to regulate the nerve signals that contract and relax muscles is impacted. This leads to the loss of or weakened voluntary muscle contractions and spasms or uncontrolled involuntary muscle contractions. 

Spasticity, a term that refers to the involuntary contraction of muscles, can affect sleep patterns, cause discomfort or even pain, and make day-to-day activities difficult. Because the muscles are frequently contracting due to spastic paralysis, muscle wasting is less of a concern than it is for flaccid paralysis; however, muscle loss, hypertonia, and hyperreflexia are major concerns, can lead to injuries, and reduce quality of life.

What Is Flaccid Paralysis?

While spastic paralysis is when the muscles become stiff and rigid, flaccid paralysis is the opposite. Muscles become weak and limp because there is a complete absence of nerve signals to the muscles. Atrophy and muscle loss are high risks for those with flaccid paralysis—fatty and connective tissues replace unused muscle as it’s broken down by the body. People with flaccid paralysis also experience an absence of voluntary or involuntary muscle contractions, loss of muscle tone, and shrinking or flabby muscles.

Why Does Loss of Muscle Function Occur?

In both flaccid and spastic paralysis, loss of muscle function occurs due to damaged or severed nerve connections from the brain or spinal cord to the affected muscles. An imbalance between excitatory (tell the muscles to contract) and inhibitory (tell the muscles to relax) signals causes loss of muscle function in spastic paralysis. Conversely, a lack of excitatory or inhibitory signals causes loss of muscle function in flaccid paralysis. 

Why Can Muscle Loss Be Dangerous?

Loss of muscles can significantly impact someone’s quality of life and health. Some of the risks associated with muscle loss include: 

• Higher risk of falls 
• Reduced independence 
• Diminished metabolic rate
• Impacted cardiovascular health 
• Risk of insulin resistance

Pressure sores are also a complex risk of muscle loss. Pressure sores can take years to heal and often cause infections, furthering a person’s risk of hospitalization. Complex management is required to help pressure sores and wounds heal and can further limit a person’s abilities. 

Symptoms will vary from person to person; however, mitigating these risks is essential regardless of the person’s condition or injury. 

What Are Treatment Options?

Doctors and clinicians can offer various treatments to address both spastic and flaccid paralysis. These treatments can range from physical therapy to medication to surgery. A healthcare team works with their patients on an individual basis and creates a treatment plan that will be the most beneficial for their patient’s health, physical ability, and condition or injury. 

Physical therapy and occupational therapy are often prescribed for people with both spastic and flaccid paralysis in an effort to manage spasticity and reduce muscle loss through rehabilitative exercise. However, having access to exercise equipment at home is crucial for supplementing a patient’s therapy plan of care and maximizing rehabilitation results. FES exercise technology bridges the gap between exercise that can be done in the clinic and at home. 

There are several FES devices available for all different forms of paralysis, but FES cycling is beneficial for a variety of conditions—including stroke, Multiple Sclerosis, spinal cord injuries, and more. A study by Ohio State University found that FES cycling is not only effective in limiting muscle loss and atrophy but actually significantly increases muscle mass when used regularly. FES cycling also reduces the occurrence of spasticity in patients—making FES cycling a great rehabilitative tool for both spastic and flaccid paralysis. 

Find Relief with MyoCycle’s FES Exercise

MYOLYN is dedicated to providing relief and rehabilitative exercise through our MyoCycle for both clinical and at-home use. One of our users, Todd, was experiencing both muscle atrophy and spasticity after a spinal cord injury. After receiving his MyoCycle, his spasticity decreased with regular use, and he noticed an increase in muscle mass—as well as improvements in his confidence and mental health. 

If you can relate to Todd’s story and want to see relief and rehabilitation from paralysis, our team is here to help. Learn how the MyoCycle can help improve your quality of life, and reach out to our team for more information.