The key difference between rigidity and spasticity is that rigidity is a condition of increased muscle tone due to injuries to basal ganglia linked to the thalamus, while spasticity is a condition of increased muscle tone due to damage to nerve pathways within the brain or spinal cord.
Hypertonia is an abnormally increased muscle tone due to upper motor neuron pathology in the brain or spinal cord. It is a condition found in both babies and adults. Hypertonia is characterized by an excess of muscle tone, leading to stiffness and difficulty in moving the arms or legs. Rigidity and spasticity are two conditions of increased muscle tone or hypertonia. However, they are different conditions with different causes.
CONTENTS
1. Overview and Key Difference
2. What is Rigidity
3. What is Spasticity
4. Similarities – Rigidity and Spasticity
5. Rigidity vs. Spasticity in Tabular Form
6. FAQ – Rigidity and Spasticity
7. Summary – Rigidity vs. Spasticity
What is Rigidity?
Rigidity refers to muscle stiffness or tension. Rigidity happens when muscles contract for a long period of time due to stress, certain medications (statins), and underlying conditions such as amyotrophic lateral sclerosis, chronic fatigue syndrome, dystonia, Lyme disease, repetitive strain injury, rheumatoid arthritis, bacterial and viral infections, pinched nerves, etc. Moreover, rigidity is characterized by the inability of the muscles to relax normally and sharp pain that makes it difficult to move muscles.
Muscle rigidity can be diagnosed through physical evaluation, blood tests, MRI, CT scan, electromyogram, and ultrasound. Furthermore, muscle rigidity can be treated by applying a warm compress or heating pad, gently stretching stiff muscles, avoiding strenuous activity, and encouraging the muscles to relax through massage, yoga, tai chi, medications, physical therapy, and surgery.
What is Spasticity?
Spasticity refers to feelings of muscle stiffness and a wide range of involuntary muscle spasms. The symptoms of muscle spasticity may include muscle tightness, joint stiffness, involuntary jerky movements, exaggeration of reflexes, unusual posture, abnormal positioning of fingers, wrists, arms, or shoulders, muscle spasms, involuntary crossing of legs, difficulty in controlling muscles that used to speak, muscle contraction that limit range of motion, pain in the affected muscles and joints, back pain and difficulty moving. Spasticity can be caused by brain injury, spinal cord injury, stroke, cerebral palsy, multiple sclerosis, amyotrophic lateral sclerosis, hereditary spastic paraplegias, adrenoleukodystrophy, phenylketonuria, and Krabbe disease.
Muscle spasticity can be diagnosed through physical examination with neurological testing and imaging testing such as MRI. Furthermore, treatment options for muscle spasticity may include medications such as botulinum toxin, baclofen, diazepam, phenol, and tizanidine, stretching exercises, avoiding extreme hot or cold temperatures, wearing loose-fitting clothes, getting plenty of sleep, and changing the position often at least every two hours.
What are the Similarities Between Rigidity and Spasticity?
- Rigidity and spasticity are two conditions that result in increased muscle tone or hypertonia.
- Both conditions are characterized by muscle tightness and stiffness.
- Both conditions can be diagnosed through physical evaluation and imaging testing.
- They can be treated through medications and home remedies.
What is the Difference Between Rigidity and Spasticity?
Rigidity is a condition that results in increased muscle tone due to injuries to the basal ganglia linked to the thalamus, which controls the coordination of movement, while spasticity is a condition that results in increased muscle tone due to damage to nerve pathways within the brain or spinal cord which control movement and stretch reflexes. Thus, this is the key difference between rigidity and spasticity. Furthermore, rigidity affects all muscles surrounding a particular joint equally, but spasticity does not affect all muscles surrounding a particular joint equally.
The infographic below presents the differences between rigidity and spasticity in tabular form for side-by-side comparison.
FAQ: Rigidity and Spasticity
What is the test for spasticity?
The pendulum test assesses spasticity
What are the two types of rigidity?
Lead pipe and cogwheel rigidity are two types of rigidity.
How do you stop rigidity?
You can decrease rigidity by frequently moving throughout the day.
Summary – Rigidity vs. Spasticity
Rigidity and spasticity are two conditions that cause increased muscle tone or hypertonia. Rigidity occurs due to injuries to the basal ganglia linked to the thalamus located on the base of the brain. Spasticity occurs due to damage to nerve pathways within the brain or spinal cord, which control movement and stretch reflexes. So, this summarizes the difference between rigidity and spasticity.
Reference:
1. Aubrey Bailey, PT. “Muscle Stiffness: Symptoms, Causes, and Treatment.” Verywell Health.
2. “Spasticity Causes, Symptoms, and Treatments.” WebMD.
Image Courtesy:
1. “02 Types of hypertonia” By Venkateswaran Ramanathan, Dipti Baskar and Hariswar Pari – Ramanathan V, Baskar D, Pari H. ' Seatbelt Effect' of Spasticity: Contrasting Velocity Dependence from the Clasp Knife Phenomenon. Ann Indian Acad Neurol. 2022 May-Jun;25(3):517-519. doi: 10.4103/aian.aian_817_21. Epub 2022 Jun 24. PMID: 35936584; PMCID: PMC9350785. (CC BY-SA 4.0) via Commons Wikimedia
2. “Spasticity and muscle contracture in the hand” By Interactive Conte (CC BY-NC-SA 2.0 DEED) via Flickr