Motor Examination Flashcards
What signs are seen with upper motor neuron lesions?
- weakness
- increased reflexes
- increased tone
What signs are seen with lower motor neuron lesions?
- weakness
- atrophy
- fasciculations (muscle twitch)
- decreased reflexes
- decreased tone
What is muscle tone?
resistant to passive stretch
What neural contributions do we see towards muscle weakness?
- # of motor units recruited
- discharge frequency
- type of motor units recruited
What is weakness in the context of neuropathology? How does it present?
- inability to generate force
- inability to correctly and/or adequately recruit or modulate motor neurons
- loss of movement/power
- lack of muscle activity/immobility
What types of neurological damage can lead to weakness?
- cortical lesion
- lesion in descending pathway
- disruption of impulses from alpha motor neurons
- peripheral nerve injury
- synaptic dysfunction at neuromuscular junction
- damage to muscle tissue
What are the different ways that weakness is defined with neurological injury?
- paralysis or plegia - total loss of muscle activity
- paresis - mild/partial loss of muscle activity
What movements are seen with an upper extremity flexor synergy?
- scapula retraction and elevation
- shoulder abduction and ER
- elbow flexion
- supination
- wrist and finger flexion
What movements are seen with a lower extremity flexor synergy?
- hip extension, adduction, and IR
- knee extension
- ankle plantarflexion and inversion
- toe plantarflexion
What is spasticity? Is it velocity dependent or independent?
- resistance to movement
- velocity dependent (can move muscle slowly with no problem, but increase in tone with increase in speed)
What is hypertonia?
Is it velocity dependent or independent?
- resistance to movement
- velocity independent ex: Parkinson’s disease
How do we measure spasticity?
- quickly move muscle through PROM
- modified ashworth or Tardieu scale
What is the basic neuroanatomy behind spasticity? What is missing from the normal modulation of tone?
- damage to descending pyramidal tracts
- alteration to threshold of stretch reflex
What types of hypertonicity can we see? How do they differ in presentation? Where do we often see hypertonicity present?
- Leadpipe - constant resistance to movement through PROM
- Cogwheel - alternating episodes of resistance and relaxation
- predominantly seen in flexors
What types of posturing can we see? Describe the difference in presentation. What is the neuroanatomy involved here?
- decorticate - UE flexion, LE extension/IR/PF - brainstem lesions ABOVE red nucleus in midbrain
- decerebrate - UE and LE extension - brainstem lesions BELOW red nucleus in midbrain
What type of damage typically leads to spasticity?
cortical damage
- pyramidal damage leads to change in descending inputs of alpha motor neurons
What type of damage typically leads to rigidity?
basal ganglia
- extrapyramidal damage
What is hypotonicity? How does it present? What area of the brain do we most often see associated with this presentation?
- reduction in passive resistance to lengthening
- “floopy” - collapse into gravity, harder to excite
- cerebellum
What are the functional impairments to increased tone? (spasticity and hypertonicity)
- abnormal posturing
- misalignment
- high risk for injury during prolonged rest (skin breakdown)
- bias w/ recruitment - increased likelihood of synergistic movement
- destabilization w/ changes in position
What are the functional impairments to decreased tone? (hypotonicity)
- fall into gravity
- high risk for injury during dynamic tasks
Define coordination. What characteristics of our movement allow us to be coordinated?
- ability to move fluidly - speed, fluidity, and accuracy
- sequencing (ability to move multiple joints at once)
- timing
- grading
What is incoordination? What specific characteristics as associated with this impairment?
- movements that are awkward, uneven, inaccurate
- disruption of sequencing, timing, and grading
What is the difference between dysmetria, hypermetria, and hypometria?
dysmetria - all over the place movements
hypermetria - overshooting movements
hypometria - undershooting movements, more of a compensation
What timing difficulties do we see with incoordination?
- increased reaction times
- slowed movement times
- difficulties terminating movement
- rebound phenomenon
- dysdiadokinesia - ability to do equal and opposite rapid movements (supinate/pronate on opposite sides quickly)
What activation and sequencing problems do we see with incoordination?
- abnormal synergies
- coactivation (inability to turn off muscles when you don’t need them)
- impaired inter-joint coordination
What is dystonia? What neuroanatomy is typically involved?
- sustained muscle contractions
- damage to basal ganglia (initiation and execution of motor control)
What are tremors? What types of tremors might we see?
- rhythmic, involuntary oscillatory movement of a body part
- resting tremor - occurs while relaxed
- action tremor - occurs during voluntary muscle contraction
What are Choreiform and Athetoid movements?
Choreiform
- involuntary, rapid, irregular and jerky movements
Athetoid
- slow, writing and twisting movements
- UE > LE
Describe the secondary neuromuscular impairments we may see during a motor exam.
- ROM and alignment issues - contractures, increased stiffness, change in length/tension relationship
- Endurance Issues - decrease in central drive to spinal cord motor neurons and decrease in activity level/immobility
- Pain - muscle pain due to overworking muscles, abnormal joint loading, ROM/alignment issues
