By Julie Lynn Marks – Medically Reviewed by Jason Paul Chua, MD, PhD
Reviewed: May 12, 2022
Spasticity is a symptom or complication of many different neurological disorders in which normal muscle movement patterns are disrupted, and muscles contract, or tighten, involuntarily.
In a healthy brain and nervous system, signals along nerves instruct muscles when to tighten or relax. But people with spasticity have essentially lost some of the communication between the brain, spinal cord, and muscles, causing certain muscles to contract or remain contracted, even when it is not desired or useful.
Spasticity can be painful and can interfere with movement and functioning, making it difficult to walk, speak, and perform daily tasks.
Some common causes of spasticity include cerebral palsy, multiple sclerosis (MS), stroke, and traumatic brain or spinal injuries. But there are other possible causes as well.
While there’s no cure for spasticity, treatments are available to help ease discomfort and improve quality of life.
Signs and Symptoms of Spasticity
- Signs and symptoms associated with spasticity include:Increased muscle tone
- Pain or discomfort
- Muscle spasms
- Muscle stiffness
- Muscles that feel heavy and are difficult to move
- Contractures (permanent contraction and shortening of muscles and tendons)
- Involuntary crossing of the legs (called scissoring)
- Abnormal posture
- Bone and joint deformities
- Difficulty walking
- Difficulty speaking, eating, and drinking
While spasticity most commonly affects the leg muscles, it can also occur in the arms, neck, and torso, or trunk. Some people with spasticity only have mild pain and stiffness, while others have severe and disabling symptoms.
Specific symptoms vary from person to person and may depend on the underlying condition leading to spasticity.
For example, someone with MS is likely to experience spasticity of the leg and hip muscles, which can lead to flexor spasticity (the legs and hips lock in a bent position) or extensor spasticity (stiff muscles keep legs straight and sometimes crossed at the ankles).
A person with cerebral palsy can have spasticity in both their arm and leg muscles. Children with cerebral palsy might not show symptoms of spasticity when they’re babies, but it can become apparent during childhood.
Someone with a brain injury, spinal cord injury, or stroke may start to have signs of spasticity in various body parts in the weeks, months, or year after the injury. In these cases, the spasticity symptoms sometimes improve as the brain heals.