PD Intro?

• Parkinson's is a chronic, degenerative neurological disorder of the CNS resulting from a loss of dopaminergic neurons in the substantia nigra.
• Parkinson's is more common in men than women.
• The most common age of onset of Parkinson's is between 50-65 years of age.
• Patients with Parkinson's are separated into two groups: tremor-dominant and postural instability-dominant. This is based on which symptom is the first to arrive, and most likely the worst.
• Parkinson's arises from the death of dopamine-producing cells in the STN. The patient will see a decrease in voluntary movement.
• Death of acetylcholine producing cells in the PPN may also cause Parkinson's disease. This will lead to the excessive contraction of postural and girdle muscles.
• Neuron death will result in the dysfunction of multiple circuits that ultimately affect motor output.
• The UK brain bank diagnostic criteria for Parkinson's is the presence of bradykinesia and at least one of the following: resting tremor, postural instability, and muscle rigidity.
• The UK brain bank diagnostic criteria also states that the patient must have an absence of any other diagnosis that results in Parkinson's symptoms, and the ability to improve with dopamine replacement therapy.
• Non-motor signs of Parkinson's include sleep disturbances, cognitive changes, orthostatic hypotension, fatigue, GI issues, pain, and depression.
• Dopamine loss precedes clinical diagnoses of Parkinson's by 5 to 6 years.
• The gold standard for diagnosing Parkinson's is the presence of substantial nigra pars compact degeneration with lewy body pathology during an autopsy.
• DaTscans may be perfromed to visualize dopamine transporter levels in the brain, in order to assist in the diagnosis of Parkinson's disease.
• Pesticide exposure increases the risk of PD.
• Prior head injury increases the risk of PD.
• Rural living will increase the risk of PD>
• An occupation in the agriculture industry will increase the risk of PD.
• Caffeine, NSAIDs, smoking, and exercise have been proven to decrease the risk of developing Parkinson's disease.
• The cardinal signs of Parkinson's are bradykinesia, rigidity, resting tremor, and postural instability.
• Bradykinesia is the slowness of both volitional movements and postural responses to both perturbations and anticipatory adjustments because of impaired central drive.
• Patients with bradykinesia will have slow gait, a slow transition to stand, and delayed and insufficient postural responses.
• Patients with bradykinesia are high fall risk.
• Bradykinesia is found in at least 75% of PD patients.
• Hypokinesia is movements of reduced amplitude or a lack of automatic movements which results in decreased force output of muscles.
• Patients with hypokinesia will present with diminished arm swing while walking, decreased step length, and flat facial expression.
• Akinesia is defined as a lack of movement initiation, more prevalent with longer disease duration and severity.
• Akinesia is also known as freezing or festination.
• Akinesia presents as hesitation starting movements in tight spaces or if there is increased pressure or movement demand.
• Rigidity is increased resistance to movement in all muscles resulting from direct UMN facilitation of alpha motor neurons.
• Rigidity presents as a flexed posture, decreased axial rotation, and overall reduced joint ROM.
• Resting tremor is a tremor that occurs at rest but diminishes with movement.
• Resting tremor presents as the movement of the hands as if using the thumb to roll a pill across the fingertips. It is seen in the jaw, chin, mouth, tongue, or lower extremity.
• Falls are defined as any unexpected event that causes a person to unintentionally land on any lower surface, regardless of a sustained injury.
• About 70% of patients with Parkinsons will report falls.
• Atypical PD is defined as PD-like sensorimotor dysfunction and other signs including a more rapid disease course, early postural instability, abnormal imaging, and a poor response to dopamine-replacement therapy.
• Progressive supranuclear palsy is the most common atypical PD diagnosis. The most common symptom is significant and early axial rigidity.
• Corticobasal degeneration is an asymmetrical presentation with spasticity and clawing (excessive flexion) of the affected limb.
• Emotional lability is inappropriate emotions at weird times. This is common with progressive supranuclear palsy.
• Multiple System Atrophy presents with dysfunction of eye movement and autonomic dysfunction. Cognition is less commonly impacted.
• Lewy body dementia will present with more cognitive deficits than motor deficits.