Understanding Parkinson’s Disease & Overcoming Movement Challenges
A diagnosis of Parkinson’s Disease can be overwhelming. As you work to understand what it means for you and your family, it becomes obvious that while there’s a lot of information available, much of it is very clinical.
When you don’t know the clinical terms, it can be very difficult to understand what you’re going through, what you might expect, and how best to manage the condition to achieve the highest possible quality of life.
With this ebook, we aim to help you understand the challenges that Parkinson’s often presents. We explain why coordination and movement become so difficult, and how you can safely stay as active as possible, keeping your independence and enjoying your life.
Chapter 1: Understanding Parkinson’s Disease
Parkinson’s Disease (PD) is a progressive neurological disorder that affects all aspects of a person’s life including their movement and ability to complete activities of daily living. According to the Parkinson’s Disease Foundation, more than 10 million people worldwide currently live with Parkinson’s Disease, and 70% of those individuals will fall, which further restricts activity due to fear of future falls.1,2 Individuals with Parkinson’s have a 2-9 times increased risk of falls compared to healthy individuals of the same age.
Parkinson’s Disease is a complex disease that primarily affects motor function, but can also cause depression and cognition changes. Every person with Parkinson’s Disease presents differently, both in their symptoms and the speed of their progression.
Parkinson’s Disease affects the circuits that allow for the brain to function and enable automatic, smooth movements. As a result, many people with Parkinson’s Disease will likely show signs of altered walking mechanics at the initial stages of diagnosis, and as the disease progresses, they may experience something called freezing of gait. Although Parkinson’s Disease is a very involved neurologic disease, the latest research shows that physical therapy and external cues from technology like NexStride can significantly improve quality of life and overall mobility.
Chapter 2: What Causes Parkinson’s Disease?
Parkinson’s Disease primarily affects a structure in the middle of the brain called the basal ganglia. The basal ganglia is in charge of the regulation of movement, specifically muscle contraction, force, and coordination of movements. The basal ganglia communicates with other structures in the brain to control eye movement, thought processing, regulation of emotion, sleep and wakefulness, and motivation. This structure is also in charge of automatic motor movements like walking, changing from one motor activity to another, and knowing where your body is in space.
Within the basal ganglia is a structure called the substantia nigra. In PD, the dopamine producing neurons in the substantia nigra degenerate, which causes the symptoms seen in PD. Dopamine is a chemical also known as a neurotransmitter that excites the pathways within the basal ganglia.
The lack of dopamine seen in Parkinson’s Disease causes a decrease in the signals sent from the basal ganglia to other structures in the brain. The basal ganglia communicates with other areas of the brain, therefore there are more than just motor symptoms seen in PD. The basal ganglia works with the limbic system, which controls emotions, the oculomotor system controlling eye movements, and the prefrontal cortex associated with cognitive changes.
Scientists still haven’t found exactly why people develop PD, though research shows there may be a correlation with genetics, environment (specifically herbicides and pesticides), age over 60, and male sex.
Chapter 3: Symptoms of Parkinson’s Disease
Parkinson’s Disease is a neurodegenerative disease which means the symptoms seen can get worse over time. PD is also a very complex disease with both motor and non-motor symptoms, and the symptoms present differently in everyone. The most common symptoms of Parkinson’s will be discussed below, but it is important to note individuals with PD may not experience all of these symptoms and they progress at different rates in everyone.
Motor Symptoms:
Tremors:
Tremors are a very common symptom in PD, with 80% of individuals experiencing this symptom.
Tremors are the uncontrollable slow, rhythmic shaking which are typically seen at rest in PD. The severity of PD is classified by if a person has tremors on one side or both sides. 10 Bradykinesia: Bradykinesia, or slow movement, is a very common symptom of Parkinson’s Disease. The reduction in speed of movement reduces the ability for muscles to produce force.
Bradykinesia causes slower and smaller movements. For example, the average walking speed of someone with PD is 94 cm/s whereas a safe speed to cross a crosswalk is 120 cm/s. If someone is bumped or missteps, they may not be able to step fast enough to catch themselves.
Postural control:
Postural control is the ability to maintain balance. Overall postural control is decreased in individuals with Parkinson’s Disease due to extreme stiffness in the trunk muscles. Postural instability has shown to begin within the first two years of diagnosis for about one third of patients. People with PD are affected in multiple areas of postural control including their balance while standing and balance during dynamic activities like walking. When someone has an outside perturbation, their reflexes aren’t effective to catch themselves like a healthy individual due to the decreased ability for their muscles to create power as seen with bradykinesia.
Gait changes:
Gait (walking) changes are the main motor symptom seen in Parkinson’s Disease. Bradykinesia, rigidity, and postural instability all contribute to the gait disturbances seen. Specific changes include reduced walking speed, increased time with two feet on the ground (shuffling), and decreased step length. These gait changes are increased during the “off” stage of medication or when the dose is wearing off.
Rigidity:
Rigidity seen in Parkinson’s Disease is when there is a contraction of all the muscles in the trunk leading to overall stiffness and stooped posture. This increased stiffness in the trunk can significantly affect balance, and also cause increased muscle fatigue which can decrease the control of balance. Luckily, the medication used to treat PD, Levodopa, can significantly improve rigidity.
Falls:
The motor symptoms seen in Parkinson’s Disease contribute to the increased risk of falls. Individuals have increased risk of fall due to decreased postural control and bradykinesia. Not only are falls critical with the potential consequences of injury, but they can lead to fear of falling which affects quality of life. 53% of individuals with Parkinson’s Disease report fall-related activity avoidance due to their fear.
Freezing of Gait
This symptom is extensively discussed in the Freezing of Gait section. It is defined as reduced ability to step forward despite the intention to walk.
Non-Motor Symptoms:
Cognitive changes:
Parkinson’s Disease involves a structure in the brain called the prefrontal cortex that causes changes in thought processing. This is important because it affects the ability of a person to plan a movement—specifically preparation, initiation and execution of a movement. Changing direction such as turning and performing tasks one after another are difficult for individuals with Parkinson’s Disease that have cognitive decline. It also affects the ability to have a goal and to make decisions. Individuals with cognitive deficits have an increased chance of experiencing Freezing of Gait.
Dual tasking:
Dual tasking is when there is a motor task and cognitive task being performed at the same time such as walking while talking. Walking changes increase during a dual motor and cognitive task because they are distracted with their through processes and can’t think about walking.
Saccade frequency:
Individuals with Parkinson’s Disease have decreased frequency of saccades or fast eye movements between the areas of the room a person is looking at. Eye saccades help assess visual information in a room for someone to pay attention to while they walk. This plays a role in spatial awareness and overall attention to one’s surroundings during motor activities like walking. It plays a role in visual observation which could lead to trips and falls.
“It’s a very humbling disease. I mean, you’re humbled because you know it’s your own independence and all of a sudden you don’t have it anymore. You want to take a step, and you can’t.” – Earl, a person with Parkinson’s
Hypophonia:
Hypophonia refers to the soft, hoarse, and monotone voice that many individuals with Parkinson’s Disease have. This is because there are changes in the vocal cord structure, not allowing for proper vibration of the vocal cords to produce sound.
“I would describe living with Parkinson’s as a big challenge sometimes grueling”– Barbara, a person living with Parkinson’s.
Depression:
50% of those with Parkinson’s Disease will experience depression during the course of their diagnosis. Those with PD have changes in the neurotransmitters dopamine, norepinephrine, and serotonin which all regulate mood and motivation, therefore depression is very common. It is very important to discuss these changes in mood with a doctor.
Sleep:
Sleep disturbances are extremely common in individuals with PD. Individuals with PD sleep an average of 5 hours per night. This is due to a combination of factors including sleep apnea, insomnia, night time urinary frequency, and nighttime hallucinations.
Fatigue:
Fatigue is seen in early PD and can come before motor symptoms. Fatigue does not often improve with medication. It has been shown individuals with deficits in executive function or cognition may have increased fatigue. The symptoms of Parkinson’s disease can affect every aspect of life.
Chapter 4: Treatment for Parkinson’s Disease
Since Parkinson’s Disease is such a complex disease, there are many approaches to treatment. This treatment can include medication, physical therapy, and sometimes surgery.
Medication:
The medication treatment for Parkinson’s Disease is called dopaminergic replacement therapy. The medicine is not only the chemical dopamine, because dopamine cannot cross the barrier from the blood to the brain. The most common medicine is called Levodopa, and it is converted to dopamine once in the brain. It is often prescribed with another medicine called Carbidopa to help it cross that blood brain barrier. The decision of type of medication and dosing will be done by a neurologist. Medication improves many motor symptoms but it does not improve postural instability which plays a role with balance. Additionally, certain aspects of walking such as overall speed and steps per minute do not improve with medication. Physical therapy in conjunction with medication has the greatest effect on improving motor symptoms. Levodopa does have a decreased effect long term, which can be associated with worsening of motor symptoms. This is why alternative, non-pharmaceutical, and non-invasive technologies such as the NexStride are so critical.
Deep Brain Stimulation:
Deep brain stimulation (DBS) is sometimes used for individuals with Parkinson’s Disease, and the surgery is performed later in the disease process for individuals who have decreased effect from medication. DBS has shown to help with motor symptoms, gait, postural stability, speed, and overall function. Deep brain stimulation is a surgery where small wires are placed in the brain to send electrical pulses. This is not done in individuals who have had PD for less than 4 years.
Physical Therapy:
Physical therapy has been shown to help walking and mobility, overall disability, and ability to perform activities of daily living. Research has shown that although it is slower, individuals with Parkinson’s Disease can learn new motor skills. It is important to note that individuals with PD who experience freezing of gait have a more difficult time with motor learning than those who don’t experience FOG.
The following section will address the broad approach of physical therapy including strengthening, stretching, balance training, gait training, and external cues.
Strength and balance training:
Strength and balance training has shown to significantly improve gait velocity and quality of movement, and can carry over to the “off”-medication phase long term. Individuals with PD have shown to have significant decreases in overall strength, and research has shown that long term strength training programs can help individuals with PD increase their strength. It is important to note that physical therapy with focus on balance training can significantly improve postural instability, which is one of the motor symptoms that is not helped with medication. Evidence shows that balance training can significantly reduce the number of falls and severity of falls.
Agility training:
Higher level agility training is critical in physical therapy. This type of training can be performed in environments that Freezing of Gait normally occurs. Agility is important to practice increased speed and amplitude of movements to address bradykinesia, as well as quickly changing movements, and balance practice.
Aerobic exercise:
Walking programs have shown to improve gait, quality of life and medication effectiveness.
Aerobic exercise has been shown to increase neuroplasticity due to improvements in brain health and strengthening of the circuits in the brain. Research on animal models have shown improved cognitive changes and automatic motor control in individuals with PD.
External cues:
Those with Parkinson’s Disease have difficulty with deciding where to pay attention, which makes visual and audio feedback helpful as they can encourage where to focus. Cueing has shown to significantly reduce FOG episodes. Although most research has shown that cueing is effective primarily while the cues are occurring, there is some evidence there can be carry over when the cues are not being used. There are two strategies to using cues. One strategy is to improve gait mechanics, to prevent freezing of gait from occurring, because freezing often occurs when gait mechanics deteriorate. The other is known as a “rescue strategy” to assist someone who is currently experiencing freezing of gait. This rescue strategy can occur by facilitating where to pay attention, and it also can help initiate steps during FOG. Individuals experiencing FOG have difficulty deciding which leg to use to step forward. Cueing helps create a specific focus on their walking, allowing someone to shift their attention from an outside trigger that may be causing FOG.Visual cues are critical because the basal ganglia normally tells your body to switch from one movement to the next automatic movement. When the basal ganglia isn’t functioning correctly as is seen in Parkinson’s Disease, an external cue such as a laser to step over, as seen in the NexStride, can help to bypass the basal ganglia and thus assist with walking.
Visual cues have shown to significantly improve gait. Specifically, visual cues can help with sizing step length, as patients tend to have shorter step lengths with PD. Visual cues have also shown to help improve fast eye movements, which assists with their spatial awareness and can be maintained during dual tasking.
Auditory cues have shown to decrease the number of Freezing of Gait episodes during step initiation, turning, and obstacles.Auditory cues have shown to increase gait velocity, step length, steps per minute, and improve Freezing of Gait & Parkinson’s Disease the variability of gait. Individuals can use auditory cues if an obstacle is coming up, to help prepare their gait before they reach the obstacle. Auditory cues help with timing of gait and coordination between limbs.
Chapter 5: Freezing of Gait
As discussed earlier, Freezing of Gait (FOG) is defined as an episodic inability to step forward despite the intention to walk. It is most commonly experienced when turning, initiating movement, or when faced with distractions. FOG negatively impacts quality of life, daily function and can contribute to falls and injuries.
Dysfunction of the locomotive network in the brain (the program in charge of movement) is experienced by people with progressive neurological disorders such as Parkinson’s Disease.
This degeneration causes a disconnection between the brain’s intent to walk and the body’s ability to initiate steps.
It is essential to note the other lesser-known neurological disorders that can also cause FOG: Progressive supranuclear palsy, corticobasal degeneration, multiple system atrophy, and normal pressure hydrocephalus.
How does FOG happen?
Our brains are programmed to walk automatically, without the need to consciously coordinate the motor plan of each step. In healthy individuals, multiple pathways in our brain coordinate activating our muscles to initiate steps, provide postural stability, and adjust our steps for dynamic balance while walking. This feedback loop is incredibly complex and requires complete synchronization to work correctly. Individuals with Parkinson’s disease lack the automaticity of walking, meaning, they have to consciously think about each step. Therefore, any disruption requiring dual tasking (e.g. talking while walking) can cause FOG, as there is an overload in the cognitive resources available.
What are the triggers of FOG
Freezing of Gait can be triggered by specific activities or circumstances that demand a change in movement. Additionally, a variety of emotional and environmental factors can trigger FOG.
Freezing of gait has shown to have various triggers. Motor triggers can include gait initiation or turning. Physical triggers can include obstacles such as a doorway or stepping into an elevator. Cognitive triggers can include feeling anxious or distracted. Individuals often develop anxiety due to their fear of experiencing FOG in a social setting.
How does FOG affect people?
The effect of Freezing of Gait is completely disabling. Individuals who have used NexStride have described FOG as feeling like, “your feet are glued to the floor,” or “stuck in a box of cement.” For individuals who experience this condition, everyday tasks become difficult, such as the inability to walk within their home or cross the street without freezing.
Not only does this phenomenon take away people’s independence, but it is also a leading cause of falls which can lead to cognitive impairment, physical injury, and fear of future falls.
For people living with Parkinson’s Disease, more than 80% will experience FOG during the course of the disease.
Chapter 6: NexStride
NexStride is the first multi-cue daily assist device that uses visual and auditory cues to help overcome freezing of gait. As discussed, evidence has described that auditory and visual external cues can increase step length and velocity, as well as reduce Freezing of Gait episodes.
Research has shown that technology that provides external cues can be significantly impactful because it can provide both feedforward and feedback information. NexStride provides feedforward information, meaning it provides information about where to step in the future of your path of walking as well as concurrent feedback, or feedback in that moment with the metronome.
“NexStride can give people back their mobility in their life, essentially, and keep them active, which is a key part of managing their symptoms of Parkinson’s–to stay as active as possible and safely as possible” – Maria, Physical Therapist
As stated previously, cues can be initiated before an individual reaches an obstacle to prevent FOG. It has been shown that the optimal delivery of devices with visual and auditory cues like NexStride can help anticipate an event and prevent FOG from occurring. 5 Research has also shown that devices that provide visual cues along the walkway can be significantly impactful in helping prevent and relieve FOG.
The work of NexStride is to help those experiencing FOG to get back on their feet and allow for a normalized way of life, one step at a time.
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