Physiology and Basal Ganglia Involvement

Parkinson's Disease (PD) is a progressive neurodegenerative disorder characterized by the degeneration of dopaminergic neurons in the substantia nigra, a part of the basal ganglia. The basal ganglia play a crucial role in movement control by regulating motor planning, initiation, and execution. In PD, dopamine deficiency disrupts these pathways, leading to significant motor impairments.

Role of Basal Ganglia in Movement

The basal ganglia help facilitate smooth, coordinated movements by modulating signals between the motor cortex and spinal cord. Dopamine plays a critical role in fine-tuning these signals, ensuring proper initiation, execution, and termination of movements. In Parkinson's Disease, the loss of dopamine disrupts this process, causing delayed motor initiation, reduced movement amplitude, and impaired motor sequencing. This dysfunction manifests as bradykinesia, difficulty controlling speed and amplitude, along with challenges in performing complex motor tasks requiring fine control and coordination. Patients may also exhibit difficulty in dual-tasking, where cognitive and motor tasks need to be performed simultaneously.

Common Signs and Symptoms in PD Patients

The hallmark "TRAP" symptoms in PD include:

1. Tremor: Resting tremor, often unilateral, visible when the limb is at rest. It can worsen with stress or fatigue and may decrease during voluntary movement.

2. Rigidity: Both lead pipe (consistent resistance throughout ROM) and cogwheel (jerky resistance at specific points in ROM) rigidity reduce movement fluidity.

3. Akinesia/Bradykinesia: Slowness or absence of movement. Akinesia refers to the inability to initiate movement, while bradykinesia describes the slowness of movement and reduced movement amplitude, making everyday tasks challenging. These symptoms can lead to difficulties with basic tasks like buttoning a shirt or writing.

4. Postural Instability: Flexed, stooped posture with increased fall risk. Postural instability arises from impaired balance and a forward-leaning posture, making it difficult to maintain upright positioning and recover from external perturbations, further elevating fall risk. This can result in an increased likelihood of falls, particularly during directional changes or walking in narrow spaces.

There are many other signs and symptoms beyond TRAP, especially across different subtypes of PD, but those will be covered in a future edition of this newsletter. Identifying these other symptoms is vital as they can impact safety and quality of life. For example, reduced olfactory function may impair a patient’s ability to detect smoke or gas leaks, emphasizing the importance of ensuring functional smoke detectors in the home. Freezing episodes, another critical symptom, occur when a patient experiences a sudden, temporary inability to move during functional activities, such as walking. These episodes often occur in transition spaces like doorways or floor transitions. Physiologically, freezing is linked to deficits in the basal ganglia's "go-no-go" pathways, which regulate the initiation and inhibition of movement. The impaired communication between the direct (go) and indirect (no-go) pathways results in conflicting motor signals, causing the patient to get "stuck." Other symptoms such as autonomic dysfunction may lead to orthostatic hypotension, increasing fall risk. It's our professional responsibility to identify these things so we can educate our patients as needed.

PD Progression Overview

Sadly, PD is a progressive disease and it’s important for clinicians to recognize and have an understanding of what stage a patient is in so they can properly tailor treatment and education. Here is a simple breakdown of the PD broken into early, middle, and late stages.

Early/Mild PD: Minimal cognitive and motor impairments with movement symptoms often unilateral. Independence is maintained, and medications effectively manage symptoms. Preventive strategies include regular exercise and community classes. Compensatory strategies may involve education on the disease process and the use of adaptive devices if necessary.

Middle/Moderate PD: Increasing severity of motor and cognitive impairments with mild to moderate activity limitations. Symptoms often present bilaterally, including balance issues and freezing episodes. ADLs may require assistance. Preventive strategies focus on regular exercise to maintain motor function, while compensatory strategies include assistive devices, home modifications, and caregiver education.

Late/Advanced PD: Severe motor and cognitive impairments with significant activity limitations. Most patients require assistance with all ADLs and mobility, often being wheelchair-bound. Preventive strategies aim to maximize posture and out-of-bed time, while compensatory strategies emphasize caregiver training, pressure relief, and psychological support.

Importance of Physical Therapy in PD Management

Physical therapy plays a critical role in managing PD symptoms and improving quality of life. Evidence shows that PT can help with improving balance, reducing fall risk, and enhancing functional mobility, ultimately empowering patients to maintain greater independence for longer periods¹. PT also provides strategies to manage symptoms such as freezing episodes and bradykinesia, ensuring patients can safely participate in daily activities. Consistent engagement in PT interventions can significantly enhance long-term health outcomes and delay functional decline. The following provides a simplified summary of the current evidence on how physical therapy can positively influence individuals with Parkinson's Disease:

1. Improved balance and fall prevention² .

2. Increased mobility and gait efficiency³ .

3. Enhanced functional strength and endurance⁴ .

Evidence-Based interventions for PD

Now, let’s focus on the core of this newsletter: practical strategies for when a patient with Parkinson’s Disease (PD) is in front of you seeking help. How can we ensure optimal outcomes supported by current research? The following evidence-based interventions, recommended by the Academy of Neurologic Physical Therapy, outline best practices for achieving positive results.

• Moderate to High-Intensity Aerobic Exercise: Aerobic Training: Engaging in moderate to high-intensity aerobic exercises, such as treadmill walking or cycling, can improve cardiovascular fitness and reduce motor symptoms in individuals with Parkinson's Disease. Aerobic exercise has been shown to enhance oxygen uptake and utilization, which is crucial for overall physical endurance and can contribute to improved mobility and reduced fatigue^1,5 .

• Resistance Training: Implementing resistance exercises targeting major muscle groups enhances muscle strength and functional mobility. Tailoring the intensity and progression of resistance training to the individual's capabilities is crucial for optimal outcomes. Tailored based on the stage of PD. Early stages focus on progressive resistance training (PRT) to build strength, while later stages emphasize maintaining current strength for functional tasks. Example: Sit-to-stand exercises using progressively increasing resistance. Strength training can lead to improvements in muscle force production, which is essential for other daily activities such as rising from a chair or climbing stairs^1,5 .

• Balance Training: Incorporating exercises that challenge balance can reduce fall risk and improve postural stability. Activities may include standing on one leg, tandem walking, or using balance boards. Balance training addresses postural control deficits common in Parkinson's Disease, thereby enhancing stability during both static and dynamic activities and reducing the likelihood of falls^1,5 .

• Task-Specific Training: Practicing functional activities directly related to daily tasks can enhance motor learning and independence. Repeated practice of activities like transferring from a chair, bed mobility, or reaching tasks can improve the ability to perform these tasks with less assistance. Task variation and repetition are key for building lasting motor patterns^1,5 .

• Gait Training: Gait training targets walking mechanics, such as improving step length, stride symmetry, and walking speed. It can also address freezing episodes and gait abnormalities often seen in PD. Techniques may include treadmill training or exaggerated step length exercises to help normalize walking patterns^1,5 .

• External Cueing: External cueing strategies use visual, auditory, or tactile prompts to enhance movement quality. For example, visual floor markers can encourage step length improvements, while rhythmic auditory cues like a metronome can help regulate step timing. These strategies can be particularly effective in reducing freezing episodes and improving walking efficiency^1,5 .

Implementing these evidence-based interventions can significantly contribute to the management of Parkinson's Disease, promoting better health outcomes and quality of life for patients. Furthermore, these evidence-based interventions are crucial in managing the progressive motor and functional challenges associated with Parkinson's Disease. By targeting specific deficits such as balance, gait mechanics, strength, and task execution, physical therapists can help patients maintain independence and reduce fall risk. A comprehensive approach that includes aerobic, resistance, balance, and task-specific training, along with external cueing, ensures a holistic strategy to optimize patient outcomes.

Importance of Community-Based Exercise for Individuals with PD

Community-based exercise programs play a significant role in the long-term management of Parkinson's Disease. According to the Academy of Neurologic Physical Therapy, such programs can enhance patient outcomes by providing ongoing physical activity, peer support, and a structured environment that promotes adherence to exercise routines. These programs are designed to complement traditional physical therapy by fostering long-term physical and functional improvements.

Two widely recognized community programs for PD patients include Rock Steady Boxing and PWR! Moves. Rock Steady Boxing incorporates non-contact boxing drills aimed at improving balance, strength, and coordination, while PWR! Moves focuses on functional, high-intensity whole-body movements to enhance mobility.

These programs have been shown to improve physical performance, reduce fall risk, and contribute to better overall quality of life. A study published in the Journal of Neurologic Physical Therapy highlights that participation in community-based exercise classes significantly improves mobility, balance, and patient confidence⁶ .

It is essential for clinicians to be familiar with local resources available to their patients. Programs such as Rock Steady Boxing and PWR! Moves are available across the U.S. and can often be found in local community centers and YMCAs. Staying informed about such options empowers clinicians to provide comprehensive care and encourage patients to engage in lifelong physical activity for better health outcomes.

Case Study: Parkinson's Disease Patient Evaluation and Treatment

Patient Case: Mr. John Doe, a 68-year-old male, presents to physical therapy with a referral for balance difficulties, frequent falls, and increasing difficulty with daily activities. He was diagnosed with Parkinson's Disease three years ago and reports worsening tremors and freezing episodes, especially when walking through narrow doorways. He uses a single-point cane but feels unsteady. He describes a fear of falling, leading to decreased physical activity and social participation. Mr. Doe has a history of hypertension, managed with medications, and no prior surgical history. His goal is to improve his walking ability and regain confidence in performing all ADLs independently.

Evaluation:

• Cranial Nerve Exam: Normal except for slight hypophonia (soft voice) noted, which is common in Parkinson's Disease.

• Cognition: Mild delay in processing speed with intact memory and orientation (MoCA score 26/30). No evidence of significant cognitive decline.

• Objective Postural Assessment: Moderate forward flexed posture with reduced lumbar extension and thoracic kyphosis. Decreased arm swing bilaterally with asymmetry more pronounced on the right side. He demonstrates festination with walking initiation and a narrow base of support.

• Range of Motion (ROM): Mild limitations in cervical rotation and thoracic extension, contributing to decreased postural control and head positioning during gait.

• Strength: Mild generalized weakness in bilateral lower extremities (4/5), most notably in hip extensors and ankle dorsiflexors, contributing to decreased postural control and gait mechanics.

• Sensation, Proprioception & Kinesthesia: Intact proprioception in the upper body but mild decrease in light touch and vibratory sensation noted in bilateral feet, potentially contributing to balance deficits.

• Tone: Mild cogwheel rigidity noted in bilateral upper extremities, more pronounced on the right side.

• Balance:

  • Berg Balance Scale: 42/56, indicating moderate fall risk. Notable difficulties were observed in tasks involving dynamic balance, such as turning 360 degrees, standing unsupported with eyes closed, and tandem stance, reflecting deficits in anticipatory balance and reactive balance control. Indicates moderate fall risk.

  • Single Leg Stance: Unable to hold for longer than 5 seconds bilaterally.

• Gait Assessment:

  • Reduced step length and shuffling gait pattern.

  • Mild freezing episodes noted, particularly when initiating movement and during turns.

  • Decreased cadence and step asymmetry noted with compensatory wide base of support.

• Functional Measures:

  • Timed Up and Go (TUG): 14 seconds (borderline fall risk range).

  • 10-Meter Walk Test: 0.7 m/s, below the functional walking speed for community ambulation.

  • Five Times Sit-to-Stand Test: 16 seconds, indicating reduced lower extremity strength and functional capacity.

Initial Treatment Plan:

The initial treatment plan for Mr. John Doe will focus on improving functional mobility, addressing fall risk, and increasing his confidence during daily tasks. A multi-modal approach will be used to incorporate elements of aerobic exercise, balance work, strength training, and task-specific practice integrated into meaningful activities.

To address both balance deficits and freezing episodes, sessions will begin with a dynamic warm-up, including large-amplitude movements inspired by LSVT BIG principles to promote improved movement quality. Exercises like reaching in multiple planes while stepping forward and backward will target anticipatory balance while introducing controlled weight shifting.

Gait mechanics will be addressed through obstacle negotiation drills, where John will practice stepping over cones and around barriers to challenge his dynamic balance and reduce freezing triggers. Auditory and visual cues will be integrated, such as metronome pacing and visual floor markers, to encourage consistent step length and reduce festination.

To build strength and functional capacity, sit-to-stand practice will be incorporated using a weighted vest to progressively overload the task. This will directly translate into his goal of improved transfers. Lower body strengthening will also include step-ups and resisted lateral stepping (if not deemed a safety hazard) to target the hip and ankle stabilizers for enhanced postural control.

Balance training will emphasize reactive and anticipatory control through multidirectional reaching tasks while standing on unstable surfaces, such as foam pads, and performing dual-task challenges like counting backward during balancing tasks.

Education Plan:

John will receive education on:

• Home Safety: Recommendations for removing trip hazards, installing grab bars, and improving lighting.

• Freezing Management Strategies: Techniques like weight shifting and using external cues (metronome or laser pointer) when approaching doorways. Techniques such as the “Stop, Stand Tall, Sway (anterior/posterior), Step” can also be taught easily for home and community use.

• Community-Based Resources: He will be introduced to Rock Steady Boxing and PWR! Moves, emphasizing their focus on functional strength, coordination, and peer support, with information on local class availability.

Your Turn: Share Your Expertise

We’ve covered a comprehensive look at Parkinson’s Disease management, including the physiology, evidence-based interventions, and a case study treatment plan for Mr. John Doe. Now, we want to hear from YOU!

• Have you encountered similar presentations in your practice?

• What evaluation tools do you find most effective for assessing balance and freezing episodes in PD patients?

• Do you agree with the proposed interventions and education strategies, or do you have additional techniques you've found successful?

• How have community-based resources, such as Rock Steady Boxing or PWR! Moves, impacted your patients’ outcomes?

Your insights can help create a richer understanding for our entire community of clinicians. Share your thoughts, strategies, and experiences with us—let's keep the conversation going and continue improving care for those with Parkinson’s Disease!

References:

1. Academy of Neurologic Physical Therapy. (n.d.). Clinical Practice Guideline for Physical Therapist Management of Parkinson Disease. Retrieved from https://neuropt.org/practice-resources/anpt-clinical-practice-guidelines/pt-management-of-parkinson-disease

2. Nascimento, L. R., et al. (2023). Effects of physical therapy in Parkinson's Disease: A systematic review. JAMA Network Open, 6(4), e238976.

3. Tomlinson, C. L., et al. (2013). Physiotherapy intervention for Parkinson's Disease: A systematic review. BMJ, 345, e5004.

4. Canning, C. G., et al. (2015). Functional outcomes following physiotherapy for PD: A meta-analysis. Physical Therapy & Rehabilitation Journal, 104(4), pzae014.

5. Oxford Academic. (n.d.). Physical Therapy for Parkinson's Disease: Evidence-Based Interventions and Their Mechanisms of Action. Physical Therapy Journal, 102(4). Retrieved from https://academic.oup.com/ptj/article/102/4/pzab302/6485202. Physical Therapy for Parkinson's Disease.

6. Regan EW, Burnitz O, Hightower J, Dobner L, Flach A. Rock Steady Boxing: A qualitative evaluation of a community exercise program for people with Parkinson's disease. PLoS One. 2024;19(12):e0309522. Published 2024 Dec 19. doi:10.1371/journal.pone.0309522

Disclaimer:

I am a current Doctor of Physical Therapy (DPT) student sharing information based on my formal education and independent studies. The content presented in this newsletter is intended for informational and educational purposes only and should not be considered professional medical advice. While I strive to provide accurate and up-to-date information, my knowledge is based on my current academic and clinical rotations and ongoing learning, not extensive clinical practice.