Spasticity

What is Spasticity?

Spasticity is a movement disorder where the muscles become tense and stiff. It can differ from person to person; sometimes it’s barely noticeable, but other times it can be so severe that it prevents the joints from moving. This stiffness is triggered when the muscles are quickly stretched or moved around.

Often, people describe spasticity as a feeling of “tightness” or “rigidity.” This condition can cause various problems, including difficulty with daily activities, maintaining personal cleanliness, comfortability, and also making it hard for caregivers to provide care. There’s also a higher chance of the muscles becoming permanently contracted, which can lead to pressure sores and infections. Furthermore, spasticity can increase the risk of bones becoming partially dislocated, or moving out of their natural position, and of abnormal bone growth within the muscles and soft tissues.

However, some people may find spasticity beneficial as it can provide them with the necessary tension to stand, bear weight, or walk. This can help reduce the risk of developing weak and brittle bones, improve blood circulation, and support better mental health.

What Causes Spasticity?

Spasticity, a symptom of a condition called the upper motor neuron syndrome (UMNS), is seen when damage occurs to the nerves within the spine or brain. This syndrome involves the parts of the nervous system that control movements, especially in muscles. When these nerves are damaged, it can result in behaviors such as excessive muscle contractions or unusual reflexes.

The UMNS syndrome can come with several other noticeable symptoms. These might include hyperactive reflexes (where muscles contract too much when stretched), or an abnormal foot reaction called an up-going plantar reflex. There can also be negative signs, such as weakness, slow movements, loss of fine motor skills, or difficulty in controlling individual movements.

This kind of nerve damage usually happens due to a loss of control over how the nervous system interacts with the spinal cord, leading to an overactive reflex response. Many different medical conditions can lead to spasticity, including strokes, cerebral palsy (a group of disorders that affect a person’s ability to move and maintain balance and posture), lack of oxygen (anoxia), traumatic brain injury, injury to the spinal cord, multiple sclerosis (a disease in which the immune system eats away at the protective covering of nerves), and other diseases that cause nerve damage.

Risk Factors and Frequency for Spasticity

Spasticity is a condition that impacts a large percentage of people with certain diseases. Approximately 35% of stroke victims suffer from it, as do over 90% of people with Cerebral Palsy (CP). It also affects about half of those recovering from Traumatic Brain Injuries (TBI), 40% of Spinal Cord Injury (SCI) patients, and between 37% and 78% of individuals diagnosed with Multiple Sclerosis (MS).

Signs and Symptoms of Spasticity

Spasticity is a muscle control disorder that can occur as a consequence of an injury or condition that affects the central nervous system, such as a stroke, spinal cord injury (SCI), or traumatic brain injury (TBI). It can also appear or worsen in people with conditions they’ve had since birth or illness, like cerebral palsy (CP) or multiple sclerosis (MS). People with spasticity have unusually tight or stiff muscles that make movement difficult.

During a medical examination, doctors typically look for signs of high muscle tone in various muscle groups. For instance, they might notice a clenched fist with the thumb tucked in, which is a common symptom of spasticity in the hand. In the lower body, spasticity often affects muscles that control the movement of the hip, knee, and ankle. Patients may have problems with shoes if the muscles controlling toe movement are constantly stiff. Other signs doctors look for include clonus (alternating muscle contractions and relaxations), spastic co-contractions (abnormal contractions in a muscle when its opposing muscle is intentionally moved), and spastic dystonia (muscle contractions causing fixed postures that are very sensitive to stretching).

Doctors often use scales to measure the severity of spasticity. The Ashworth scale, for example, rates muscle tone on a scale from 0 (no increase in tone) to 4 (the affected part is flexed or extended rigidly). The Tardieu scale grades the speed of muscle stretching and how the muscle reacts, as well as the angle at which spasticity is detected during the stretching. The Penn scale measures how frequently spasms occur.

• Ashworth Scale:
• 0: No increase in tone
• 1: Minimal resistance at the end of range of motion (ROM)
• 1+: Some resistance less than half of ROM
• 2: Increased muscle tone for the majority of ROM
• 3: Difficult movement throughout the majority of ROM
• 4: The affected part is rigid

• Tardieu Scale:
• Velocity to stretch: V1 (as slow as possible) to V3 (as fast as possible)
• Muscle reaction: 0 (no resistance) to 5 (joint immobility)
• Spasticity angle: R1 (caught at fast velocities) or R2 (full ROM when muscle is relaxed and tested at slowest velocity)

• Penn Spasm Frequency Scale:
• 0: No spasms
• 1: Spasms only caused by vigorous sensory and motor stimulation
• 2: Occasional spontaneous spasms, less than once per hour
• 3: Spasms occurring between 1 and 10 times per hour
• 4: More than 10 spasms per hour

Testing for Spasticity

Doctors may see patients with two types of spasticity, a condition characterized by muscles stiffness and tightness: one that is new and potentially a sign of an underlying nerve disease, or one that is worsening due to a known chronic nerve condition or an external factor.

When a patient has newly developed muscle stiffness, the doctor would need to understand the patient’s medical history and how their symptoms have progressed. They will ask about any signs of muscle weakness, changes in feelings or sensations, pain, issues with bladder or bowel functions, and sexual dysfunction. The doctor will also ask about the patient’s family history, travel experiences, diet, and any conditions that might have affected the patient’s immune system. Physical examination will be conducted focusing on the nervous system, specifically studying muscle tone, motor strength, reflexes, and sensation.

For cases where existing muscle tightness worsens, doctors usually check for any factors that may have triggered the change, whether the known nerve condition has progressed, or if a new disease has appeared. These triggers could be related to skin issues like ulcers, ingrown toenails, boils, or infections. Problems with internal organs, such as constipation, urinary tract infections, or stone formations may also be responsible. Suddenly stopping medications that control muscle stiffness can also worsen the condition. And finally, problems related to medical devices like ill-fitted support braces, poor seating, or malfunctioning muscle relaxant pumps can all be factors that intensify muscle stiffness.

Other painful conditions like infections, injuries, blood clots in the deep veins (also known as deep vein thromboses or DVT), or stress can also make muscle stiffness worse.

Treatment Options for Spasticity

When looking to treat muscle tightness or stiffness, known as spasticity, several factors need to be considered such as the cause of the disorder, when it appeared, other medical issues, the patient’s support system, and the overall objectives of the treatment. Spasticity treatment follows a step-by-step method, starting with simpler options and advancing to more intricate surgical procedures if necessary.

One of the first ways to manage spasticity involves identifying and avoiding things that can worsen the condition, such as infection, pain, blood clots in deep veins of the body, abnormal bone growth, bedsores, an overly full bladder or bladder stones, and ingrown toenails. It’s also important to use physical therapies like stretching, securing with a brace, casting, heat and cold treatments, pressure on the tendon, electrical stimulation of muscles, vibration, and biofeedback.

There are several medications approved by the Food and Drug Administration (FDA) for treating spasticity, including baclofen, tizanidine, dantrolene, and diazepam. These drugs can provide relief for mild to moderate spasticity and are most effective for spasticity caused by spinal cord injuries or multiple sclerosis. However, while they can reduce muscle tone and pain, they have not been proven to significantly improve function.

Baclofen works by activating certain receptors in the body called gamma-aminobutyric acid (GABA) receptors, thereby increasing the inhibitory effects within the reflex pathway. This results in less excitability in the neurons, leading to decreased input to the muscle fibers. Side effects of baclofen can include sedation and drowsiness, which patients can become tolerant of over time. Other side effects can include a higher risk of having seizures, muscle weakness, gastrointestinal symptoms, tremors, insomnia, and confusion.

Another drug, Tizanidine, enhances the inhibition of the spinal reflex by binding to nerve receptors. Side effects of Tizanidine can include sedation and drowsiness in up to half of patients, liver damage, low blood pressure, dry mouth, slow heart rate, and dizziness.

Dantrolene Sodium, unlike the previous drugs, works at the level of the muscle by blocking the release of calcium in the muscle cell. This results in a reduction of the muscle’s ability to contract, leading to less sensitivity. One important side effect is that 1% of patients suffer from liver toxicity. Other side effects include drowsiness, sedation, weakness, fatigue, numbness or tingling, diarrhea, nausea, and vomiting.

Diazepam works by increasing the inhibitory effects of GABA receptors, leading to an overall decrease in neuron firing. Its net effect is increased presynaptic inhibition and reduced reflexes. Of all the drugs discussed, diazepam is the most sedating and can lead to memory impairment and decreased REM sleep.

In addition to oral medications, spasticity can be managed with local interventions, such as nerve blocks, chemical nerve paralysis, chemodenervation with botulinum toxin, and motor point blocks.

Diagnostic nerve blocks involve injecting a local anesthetic around the nerve using electrostimulation as guidance to block nerve conduction for a few hours. This temporary measure helps plan for more permanent interventions as it allows for the temporary reduction in spasticity to be assessed.

Chemoneurolysis involves the use of agents that cause nerve damage whilst reducing spasticity. Common agents used include phenol and ethyl alcohol. These agents are injected using electrostimulation or electromyography (EMG) guidance.

A treatment using botulinum toxin is another option. It functions by preventing the release of a chemical that causes muscle contractions from the nerves.

Another management option is called an intrathecal baclofen (ITB) pump. This device allows for direct delivery of baclofen into the cerebrospinal fluid in the space right around the spinal cord. This method enables the patient to receive a high concentration of the medication directly to the spine whilst reducing the risk associated with high oral doses of baclofen.

Lastly, for the most persistent cases of spasticity, the most invasive management options are surgical. These include orthopedic surgeries like tendon lengthening, tendon transfer procedures, as well as neurosurgical procedures.

What else can Spasticity be?

When it comes to conditions that resemble spasticity, several other medical conditions are often considered. These include:

• Contractures: It’s a situation where the flexibility of a muscle, tendon, ligament, joint capsule, or skin is reduced. While similar to spasticity, contractures don’t exhibit the changes with movement or limb position that spasticity does.
• Rigidity: This is typically related to injuries in an area of the brain known as the basal ganglia. All muscles around a specified joint are generally affected equally by rigidity. Unlike spasticity, rigidity remains constant regardless of the speed of movement.
• Catatonia: This is a brain disorder in which the patient might have abnormal body postures. In this condition, the increase in muscle tone depends on the force applied to the said muscle. Often, patients with catatonia will also have symptoms like unresponsiveness, compulsive behavior, repetitive motion, staring, facial grimaces, repeating what another person says or does, and withdrawal.

Remember, it’s important for healthcare practitioners to be aware of these conditions to correctly diagnose their patients.

What to expect with Spasticity

The outlook for spasticity, a condition where muscles are continuously contracted, can greatly differ between individuals. If a patient responds positively to treatment, which could include physical exercises, therapy or medicine, they might have a better chance of controlling the constant muscle contraction symptoms.

Interestingly, as highlighted before, spasticity might also offer some benefits to the patient. It can assist with walking, which can prevent the formation of deep vein thrombosis (DVTs), clots formed within deep veins. Furthermore, it can help maintain muscle mass and fosters weight-bearing that may prevent osteoporosis, a condition that weakens the bones and makes them more likely to break.

Possible Complications When Diagnosed with Spasticity

Spasticity can lead to various complications. If it becomes severe, it can greatly disrupt everyday activities. Not only can it cause significant discomfort or pain, but it can also make maintaining personal hygiene difficult and put a strain on those providing care. These issues may then raise the probability of developing pressure sores. These sores, in turn, can cause infections and a condition called sepsis.

Additionally, spasticity can result in broken bones, partial dislocation of a joint (subluxation), complete dislocation, and an increased chance of a condition known as heterotopic ossification.

Common Complications:

• Disruption of daily activities
• Significant discomfort or pain
• Difficulty maintaining personal hygiene
• Strain on caregivers
• Development of pressure sores
• Potential for infections and sepsis
• Broken bones
• Partial or complete joint dislocation
• Increase chance of heterotopic ossification

Recovery from Spasticity

Rehabilitation is often a key part of handling a patient’s excessive muscle tightness, also known as spasticity. Beyond using medication, it’s significant to use physical treatments and therapies that have been talked about before. This process should include the patient, their family, and any other individuals who are taking care of them, to address the spasticity and agree on what they hope to achieve with the treatment and management. It’s essential to notice and stay away from harmful stimuli while keeping up with regular stretching and range of movement exercises.

Preventing Spasticity

Patients should be taught the importance of daily stretching and exercises to maintain their movement abilities. Family members and caregivers should also be well-informed about the correct way to position the patient, how to keep an eye on skin health daily, maintaining a consistent routine for bowel and bladder care, staying away from harmful factors, and recognizing symptoms of infection and pain.