Clonus after a stroke is a neurological condition that causes repeated, rhythmic muscle contractions, usually in the ankle, foot or leg. It often occurs when a muscle is suddenly stretched and may feel like shaking, bouncing or uncontrollable jerking. Learn why clonus develops after a stroke, how it affects movement and what treatments may help manage symptoms.

After your stroke...

You stretch your foot.

Or perhaps your therapist moves your ankle.

Suddenly your foot starts jerking repeatedly.

It may feel like your foot is bouncing uncontrollably.

You begin wondering...

"What is happening?"

"Why won't it stop?"

"Is this normal after a stroke?"

These concerns are very common.

Many stroke survivors feel worried when they first experience clonus.

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The Good News

Clonus is a recognised neurological complication after stroke.

Although it can be frustrating, it does not necessarily mean that your recovery is worsening.

For many people, clonus improves with rehabilitation, stretching and management of muscle tone.

Even when it persists, treatments are available that may help reduce symptoms and improve function.

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What Is Clonus?

Clonus is a series of involuntary, rhythmic muscle contractions.

It occurs because the normal signals that regulate muscle activity have been disrupted by the stroke.

Instead of the muscle relaxing after being stretched, it repeatedly contracts and relaxes in a rapid cycle.

Clonus most commonly affects:

✓ The ankle

✓ The calf muscles

✓ The foot

✓ Occasionally the knee or wrist

The movements may last for a few seconds or continue for longer periods.

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What Does Clonus Feel Like?

People describe clonus in different ways.

You may notice:

✓ Rapid jerking of the foot

✓ Repeated bouncing movements

✓ Rhythmic shaking

✓ A feeling that the muscles are "beating" or "pulsing"

✓ Difficulty controlling the leg

For some people, clonus is uncomfortable.

For others, it is simply strange and unsettling.

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Why Does Clonus Happen After a Stroke?

A stroke can damage areas of the brain that normally help control muscle reflexes.

This may cause the nervous system to become overactive.

As a result, the muscles may become excessively responsive to stretching.

This is known as an upper motor neuron lesion, which commonly causes:

✓ Spasticity

✓ Increased muscle tone

✓ Hyperreflexia

✓ Clonus

These conditions often occur together.

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Is Clonus the Same as Tremor?

No.

Although both involve involuntary movements, they are different conditions.

A tremor usually produces shaking that can occur during movement or at rest.

Clonus typically occurs when a muscle is suddenly stretched and produces rhythmic, repetitive contractions.

The movements of clonus are often more regular and predictable.

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When Does Clonus Usually Occur?

Clonus may happen:

✓ When your foot is moved upwards

✓ During stretching exercises

✓ When standing

✓ While walking

✓ When changing position

Some people only notice it occasionally.

Others may experience it frequently.

Symptoms can also fluctuate from day to day.

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Is Clonus Related to Spasticity?

Yes.

Clonus often occurs alongside spasticity.

Spasticity causes muscles to become tight and overactive.

Because both conditions result from disruption of the same neurological pathways, they commonly occur together.

If your muscles feel stiff, tight or resistant to movement, spasticity may be contributing to the clonus.

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Can Clonus Affect Walking?

Yes.

Significant clonus can interfere with:

✓ Balance

✓ Walking speed

✓ Foot placement

✓ Confidence while walking

Some people feel as though the leg is unpredictable or difficult to control.

In severe cases, clonus may increase the risk of falls.

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Can Clonus Improve?

Yes.

For some people, clonus gradually improves as the brain adapts and muscle control improves.

However, recovery varies significantly between individuals.

Some people experience:

✓ Complete resolution

✓ Partial improvement

✓ Long-term symptoms that require management

Even when clonus persists, many people learn effective strategies to minimise its impact.

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What Can Help Manage Clonus?

Treatment depends on the severity of symptoms.

Possible strategies include:

Stretching

Regular stretching may help reduce muscle tightness and decrease triggers for clonus.

Physiotherapy

Physiotherapy can help improve:

✓ Movement patterns

✓ Muscle control

✓ Balance

✓ Walking ability

Positioning and Splinting

Orthotics or positioning devices may sometimes help manage muscle tone.

Managing Triggers

Fatigue, stress and illness can sometimes worsen clonus.

Learning your individual triggers may help reduce symptoms.

Medication

In some cases, medications used to treat spasticity may be considered by your healthcare professional.

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Can Fatigue Make Clonus Worse?

Yes.

Many stroke survivors notice that clonus becomes more noticeable when they are:

✓ Tired

✓ Stressed

✓ Unwell

✓ Overexerted

Symptoms may improve after rest.

This does not necessarily mean that your recovery is worsening.

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When Should You Seek Medical Advice?

Speak with your healthcare professional if:

✓ Clonus suddenly becomes worse

✓ It significantly affects walking or daily activities

✓ You develop new weakness

✓ You experience increasing pain

✓ You are concerned about falls

Any sudden neurological change should always be assessed.

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My Perspective

Experiencing clonus for the first time can feel frightening.

Your foot or leg suddenly starts moving on its own.

You may wonder whether something serious is happening.

But clonus is a recognised complication after stroke.

It does not automatically mean that recovery has stopped.

Recovery after stroke is rarely straightforward.

Symptoms may improve, fluctuate and change over time.

Be patient with yourself.

And seek support if clonus is affecting your daily life.

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Frequently Asked Questions

Is Clonus Common After a Stroke?

Clonus is less common than weakness or fatigue but is a recognised complication, particularly in people with increased muscle tone or spasticity.

Is Clonus Permanent?

Not necessarily.

Some people experience improvement over time, while others continue to have symptoms long term.

Does Clonus Mean My Stroke Is Getting Worse?

Usually not.

Clonus is generally related to existing neurological damage rather than new damage.

However, sudden changes should always be assessed.

Can Exercise Help?

Appropriate rehabilitation exercises and physiotherapy may help improve movement and reduce the impact of clonus.

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Key Takeaways

✓ Clonus causes rhythmic, repetitive muscle contractions.

✓ It commonly affects the foot, ankle and leg after stroke.

✓ Clonus is often associated with spasticity and increased muscle tone.

✓ Symptoms may worsen with fatigue and stress.

✓ Physiotherapy and stretching may help manage symptoms.

✓ Many people experience improvement over time.

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Related Articles

Continue learning about movement problems after stroke:

Spasticity After a Stroke
Muscle Weakness After a Stroke
Why Does My Leg Shake After a Stroke?
Walking After a Stroke
Contractures After a Stroke

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About the Author

Alisia Gayle is a stroke survivor who achieved 96% neurological recovery following an ischaemic stroke.

After years of rehabilitation, she now shares practical, evidence-informed resources to help stroke survivors, carers and families better understand recovery and rebuild their lives with confidence.

Alisia is also the author of Brain Damage: My Journey to 96% Recovery, where she shares her personal stroke recovery story and the lessons she learned throughout her rehabilitation.

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Medical Disclaimer

This article is intended for educational purposes only and should not replace professional medical advice, diagnosis or treatment.

Always seek advice from your doctor or healthcare professional regarding any new or worsening symptoms.

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Final Thoughts

Clonus after a stroke...

Can feel strange.

And sometimes worrying.

But it is a recognised part of neurological recovery for some stroke survivors.

The movements may improve.

Management strategies can help.

And support is available.

Take things one day at a time.

Continue your rehabilitation.

And remember...

Recovery is not always smooth.

But progress is still possible.