Limb spasticity is a condition that causes muscles and joints to become tight or stiff. It also causes symptoms like pain and uncontrollable muscle movement. Limb spasticity can occur due to central nervous system disorders, such as multiple sclerosis, stroke, cerebral palsy, and so on. It affects the coordinated movement of upper and lower limbs, which can affect your gait and ability to do daily activities.
Botox for Limb Spasticity
Botulinum toxin or botox is a powerful neurotoxin released by bacteria called Clostridium botulinum. It's commonly used to treat wrinkles and other cosmetic concerns. It has also been approved by the U.S. FDA for limb spasticity treatment.
When botox is injected into spastic muscles, it blocks signals from the nerve to the muscle. This relaxes the muscles and prevents contractions and spasms. Depending on the pattern of limb spasticity, botox is carefully injected into the affected muscles. Its effects last for up to 12 to 16 weeks, but a patient can be injected only a few times as it can cause long-term side effects like muscle weakness.
In patients with multiple sclerosis, botox can be used to relieve tension in the elbow, wrist, finger, thumb, ankle, and toe flexor muscles.
A recent study evaluated the use and effectiveness of a form of botox, onabotulinumtoxinA, across different causes of limb spasticity. The analysis was done over a year using data from the Adult Spasticity International Registry (ASPIRE) study.
According to the research, onabotulinumtoxinA treatment improved lower limb movement over time in patients with multiple sclerosis. The study also showed that patients and researchers were satisfied with the results of onabotulinumtoxinA treatment. Further research is needed to improve botox treatment for limb spasticity linked to specific conditions.
Botox doses are individualized depending on the following:
- Size of the muscles
- Number of muscles
- Location of the muscles
- Severity of the condition
- Presence of muscle weakness
- Response to previous treatment
- Past adverse reactions to botox
Botox is generally used to treat lower limb spasticity as it hasn’t shown much effect on upper limb movement. It also can’t be used to restore range of motion at a stiff or tight joint.