When assessing a patient, it is vital to check muscle contractions. One abnormality that is common is clonus. Clonus is an involuntary muscle contraction caused by the disruption of communication between the brain and spinal cord. When muscle contractions continue for an extended period, this causes an abnormal repetitive contraction.
Clonus usually occurs in the lower extremities, most commonly in the ankle area. It can, however, occur in other parts of the body, such as the knee or elbow. If you are a healthcare professional tasked with assessing a patient for clonus, this article will provide you with the essential information you need to know.
Causes of Clonus
Clonus can be caused by a variety of factors. Some possible causes include:
- Serious head abuse
- Spinal cord damage
- Multiple sclerosis
- Traumatic brain injury
- Brain or spinal cord tumor
In some cases, clonus may also be a side effect of certain medications, such as antidepressants, antipsychotics, and antihistamines. If you are taking any medication, speak with your doctor to determine if clonus is a potential side effect.
Symptoms of Clonus
The primary symptom of clonus is a rapid succession of involuntary muscle contractions. This tends to occur in the ankle, causing the foot to move back and forth. The contractions can last for several minutes, and they tend to appear and disappear in a pattern. Some people may also experience general muscle weakness, while others may have difficulty walking or maintaining balance.
How to Assess for Clonus
To assess for clonus, your healthcare provider will first ask you to sit or lie down comfortably on a table. They will ask you to support your leg in a relaxed position, with your knee bent and your foot hanging off the table. Your healthcare provider will then provide a quick extension of the ankle, moving it from a relaxed position to an extended position. The healthcare provider will hold it in place for a few seconds, then rapidly release it. This motion will provoke clonus, commonly known as “foot bounce.”
Depending on the patient’s medical history, the healthcare provider may also elect to perform other assessments, such as reflex and strength testing. Reflex and strength testing also helps to identify any underlying conditions that may be responsible for the clonus.
Grade One Clonus
Grade one clonus is the most common type of clonus. It is characterized by two or three beats of clonus that occur before the muscle relaxes.
Grade Two Clonus
Grade two clonus occurs when the ankle is flexed more than 15 degrees. This type of clonus is more severe than grade one clonus and is typically a sign of an underlying problem.
Grade Three Clonus
Grade three clonus is characterized by a severe level of clonus that cannot easily be stopped as well as other possible signs, including hyperreflexia, and difficulty moving or walking.
When to Contact a Healthcare Provider
If you experience clonus or have any of the symptoms mentioned previously, it’s important to schedule an appointment with your healthcare provider right away. Delaying a diagnosis and treatment may lead to complications, including pain, muscle stiffness, muscle spasm, and potential nerve damage.
If you have an underlying condition, it’s vital to stay on top of your healthcare to prevent any complications such as clonus. Speak to your healthcare provider promptly if you are experiencing any new symptoms or if you have any concerns about your condition overall.
How to Treat Clonus
The treatment for clonus varies, depending on the underlying cause. If the clonus is caused by certain medications, speak with your healthcare provider to determine if an alternative medication is available.
If you have an underlying condition, such as multiple sclerosis or spinal cord damage, your healthcare provider will work with you to develop a treatment plan to manage your condition effectively. Some treatments may include prescription medications, physical therapy, occupational therapy, or surgery. In severe cases, clonus may be surgically treated with a dorsal rhizotomy or a Baclofen pump.
Clonus is an involuntary muscle contraction caused by a disruption in communication between the brain and spinal cord. Clonus can occur in different areas of the body, and ankle clonus is one of the most common. The symptoms of clonus include involuntary muscle contractions, muscle weakness, difficulty walking or maintaining balance. If you have clonus or experiencing any possible symptoms, seek medical care right away. Treatment options vary, depending on the underlying cause of clonus.
Q&A Related to How to Assess Clonus
- What causes clonus? Clonus can be caused by a variety of factors, including stroke, serious head injuries, spinal cord injuries, meningitis, multiple sclerosis, traumatic brain injury, and certain medications.
- What is the primary symptom of clonus? The primary symptom of clonus is a rapid succession of involuntary muscle contractions. This tends to occur in the ankle, causing the foot to move back and forth.
- What is grade two clonus? Grade two clonus occurs when the ankle is flexed more than 15 degrees. This type of clonus can be more severe than grade one clonus and is typically a sign of an underlying problem.
- How is clonus treated? The treatment for clonus varies, depending on the underlying cause. If the clonus is caused by certain medications, speak with your healthcare provider to determine if an alternative medication is available.
- Can clonus be surgically treated? Clonus can be surgically treated with a dorsal rhizotomy or a Baclofen pump in severe cases.
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2. Clonus. (2021, October 5). Healthline. Written by Ann Marie Griff, OTR, CHT. Retrieved November 25, 2021, from https://www.healthline.com/health/clonus.
3. Clonus. (n.d.). Cedars-Sinai. Retrieved November 25, 2021, from https://www.cedars-sinai.org/health-library/diseases-and-conditions/c/clonus.html.