Parkinson Flashcards
motor control issues in PD
- Disorders of Tone (Rigidity)
- Disturbances of Posture and Balance Function
- Movement Dysfunction (Akinesia, Bradykinesia)
- Disorders of Locomotion
major impairments in PD are mostly associated with..
initial conditions, preparation, initiation, and execution
- termination problems may arise during walking (festination/hastening)
initial conditions- problems of posture components
- Mobility (shortening of structures on the ventral surface; loss of spinal flexibility especially later in the disease)
- Force Generation (decreased strength of trunk extensors)
- Rigidity
is sway significantly increased?
no - except in long term disease
problems of posture - use of sensory information
May have increased dependence on vision
and decreased adaptive capacity to repeated stimuli in standing
- maybe impairments in proprioceptive regulation
problems of tone: neural factors
multiple potential mechanisms for rigidity. One not clearly identified as primary factor over others
problems of tone: musculoskeletal factor
Changes in the visco-elastic properties of connective tissue (increased stiffness).
problem of initiation: akinesia
- delay in initiation
- may occur in the postural component of
the movement (postural adjustment) and/or in the focal (actual) movement
what largely contributes to problems of akinesia
neural factors associated with motor planning in the preparation stage
when is akinesia revealed
with increased movement complexity
- but pts with PD can generally use advanced information
APA for stepping in PD
- Most commonly, the APA is reduced in amplitude
- L-Dopa appears to improve this
- Deep brain stimulation does not
other common impairments in APA
delays, reduced presence (absent-later disease), and/or incomplete or multiple EMG bursts
problems of execution: bradykinesia
- Slowed movement (bradykinesia) and decreased amplitude of movement (hypokinesia) are also common examination
findings
what has been attributed to problems of generating an adequate motor command? (energizing the muscular system)
- decreased speed and amplitude of simple movements
bradykinesia with a simple elbow movement
- Correct agonist recruited
- Duration of agonist EMG burst is generally normal
- decreased size of the initial agonist burst
- Movement achieved through a
series of small agonist bursts - Timing of subsequent ag/antag
preserved
what can pts with PD do to the initial agonist burst
- they can modulate it because the larger amplitude movements or those against greater loads result in larger agonist bursts
there is an instability to achieve what?
absolute levels of initial agonist activation
- scaling the agonist burst to movement demands
what does PD result in an underestimation of?
the size of the impulsive force generated by the initial agonist required to produce the desired movement.
there is some evidence suggesting that patents with PD may be…
- weak in some muscle groups even when there is sufficient time to develop maximal force.
- Rate of rise of force development (muscle activity) is impaired in PD –> This has been shown to be true despite normal maximal force production capability
brady/hypokinesia in complex movement
- Longer movement times
- Lack of coordination between phases
- Acting more sequentially than simultaneously
- Simple actions replace complex actions
brady/hypokinesia: complex movements conclusion
- Inability to combine and execute a series of motor actions that comprise a complex motor sequence
- disturbances with triggering internal generated movements (role of SMA)
(dont do well sitting up on their own)
normal function of BG is probably related to..
routine automatic execution of sequences of movements generated in cortical motor areas
problems of reactive control
- Less sequential activity with more co-contraction to platform perturbations.
- Less adaptive capacity as well
(pedunculopontine nucleus)
experiment on problems of reactive control
- Persons with PD exhibit more sway, lower LE joint torques, and lower step thresholds to perturbations
- Directional differences when perturbed forward or backward with shorter and more steps when perturbed backward.
- L dopa helped # of steps but not step length
major objective of PT for PD:
improve QoL by improving and preserving independence, safety and well-being through
exercise
goals of PT for PD
- EMPHASIS ON PHYSICAL ACTIVITY IN THE EARLY PHASE
- Improve voluntary movements (strength; speed; initiation)
- Reduce excessive rigidity
- Avoid complications of immobilization
treatment guided by stage of disease… idk if we need to know that
Treatment ideas that Dr Hanke says you need to commit to memory - truncal stiffness
make trunk movements
provide flexibility home program
Treatment ideas that Dr Hanke says you need to commit to memory - mis-scaling of movement amplitudes
use of large amplitude movements
Treatment ideas that Dr Hanke says you need to commit to memory- inability to start
mental, verbal, tactile, manual cues
Treatment ideas that Dr Hanke says you need to commit to memory - hastening
selection of proper cueing frequencies
visual line cueing
Treatment ideas that Dr Hanke says you need to commit to memory - problems with simultaneous and sequential movements
training with simple sequences
treating problems of initial conditions - tone/rigidity
- Functional axial rotation
- Stretching
- Extension
- Aerobic/forced exertion exercises
treating delayed in initiation
- Problem: Altered preparation (= delayed onset EMG)
- When postural component: Proactive balance training and/or Instruct in necessary PA’s
- When the voluntary movement component: Imitation, Imagination, Cueing
Treating execution problems - bradykinesia –> decreased amplitude and speed
- make big ballistic, high force, large amplitude movements
- exaggerate movements
execution problems - AROM, strengthening
- For those who can perform resistance exercise, forced exertion (eg, LE exercise bike) is a good approach.
- Strengthening helps if they are in a strengthening program. It doesn’t reverse the disease –> Mixed results on falls and function
treating multi-segmental movement problems
- Re-conceptualize the task –cognitive movement strategy (now called strategies for complex movement sequences)
- verbal cues at sticking points; provide key verbal cues; (clock turn, arch)
cognitive movement strategies
- Make explicit what is normally automatic
- Conscious performance of actions in which complex (automatic) activities are transformed to several separate elements that must be
executed in a set order, and which consist of relatively simple movement components. - Compensation for impaired motor planning of complex movement plans through cues and attention.
complex movement sequences
- Set and agreed upon with patient and based on individual needs.
- Perform each component of the movement sequence individually with attention.
- Identify most difficult component and practice repeatedly
- Rehearse mentally and physically
- Repetition
treating balance problems
- follow balance progression
- BOS, Sensory input, challenges to COM
biggest bang for your buck
- Aerobic exercise on motor symptoms and gait endurance (LTV)
- Treadmill training on gait speed
- Strength training on gait endurance
- Balance and gait training on balance (BBS) and gait (speed)
- CMS training on functional mobility
- Nordic walking, dance, martial arts on motor symptoms to varying degrees
- Exergaming on functional mobility (TUG) and balance (BBS)
what outcome is missing
participation
observation of the parkinsonism gait
Slow, shuffling steps, flexed posture, little trunk and UE motion, foot flat (general poverty of movement)
delayed gait initiation- 3 separate problems
- an absence of a clear and fully expressed postural adjustment
- classic “bradykinetic” responses from postural agonists;
- relatively normal postural synergy interacting with abnormal standing posture
delayed gait initiation is because of
- Impaired capacity by the nervous system to integrate and sequence postural and subsequent locomotor synergies.
- Alterations in the postural
component of gait initiation
treating delayed gait initiation
- Object visualization/imagination –> Stepping over tape, cane, someone’s foot, an imagined shoe box
- Make explicit what is normally automatic –> Shift then take a big step
- Use instruction and manual contacts in lateral and A/P directions within a functional context
short, shuffling or freezing of gait
- Altered descending input
- Disturbance in rhythm formation
festination/hastening
Possibly two types:
- one associated with FOG considered a core locomotor rhythm problem
- other being related to poor posture (flexed) and insufficient steps to control the forward momentum associated with the flexed posture.
festination- locomotor component
shortening of steps –> progressive increase of stepping cadence –> freezing of gait
- treatment: external cueing
festination- balance component
forward learning of the trunk –> small (balance corrective) steps –> fall
- treatment: address posture/balance
treating progression problems: auditory pacing
- metronome, wrist/ankle metronome, hand clapping, finger snapping, music in general, singing
- Auditory rhythmic cues improve walking speed, stride length, step frequency (from -10% up to 10% above natural frequency FOR THOSE WITHOUT FREEZING)
treating progression problems: rhythmic auditory pacing
- Click tone embedded in music: typically matched to self-selected cadence.
- May act as an external timekeeper to which the step cadence becomes entrained.
- Improved stride length during rhythmic gait facilitation may be due in part to the modulatory effect of RAS on muscle activity (triceps surae)
treating progression - visual markings
- lines on floor perpendicular to the line of
progression, effects on GRFs - produces an emotional arousal at a
behavioral level: is each line a sub-goal? - visual stimulation may promote access to
other pathways (eg, via cerebellum)
other ways to treat progression
- Treadmill training
- Consider effect of assistive device
- Thinking about taking big steps
- Nordic walking
- Cueing big steps; lifting knees up high
- Choosing a point of reference for
the patient to walk towards
adaptability: inability to adapt the gait pattern
- Difficulty changing speed and direction.
- Breakdown of complex actions / interaction between cortical and subcortical structures.
- Environmental surroundings may hinder or facilitate locomotion.
- Strategies which are used for gait stability problems work for adaptability issues and vice versa
treatment for adaptability
- explicit use of range of speeds –> especially on treadmill
- must work overground –> different environments
- provide and OFFER CUES to get through areas where change in speed or direction is needed
summary
Promote physical activity
Big movement
External cueing
Cognitive movement strategies
Warm up exercises for ROM/Rigidity
