(3) Ataxia Flashcards
What is ataxia?
loss of coordination of voluntary muscle movements
What are typical characteristics of ataxia?
- unsteady
- reeling
- clumsy
What are the inherited ataxias?
- Friedrichs
- Spinocerebellar
What are the acquired ataxias?
- sensory lesion
- cerebellar lesion
- vestibular lesion
- associated areas lesions
What is the Postural Control System (PCS)?
Ability to maintain the body in space achieving stability & orientation
What are the 3 main functions of the PCS?
- balance
- stabilization
- support the body
What tasks does the PCS carry out?
- relative position body parts
- position body in relation external forces
- info via somatosensory, vestibular & visual systems
What is sensory ataxia?
lack sensory input mould movement
What causes sensory ataxia?
- disruption of afferent input in dorsal columns
- disruption proprioceptive input
What are symptoms of sensory ataxia?
- wide based stamping gait with eyes fixed on ground
- high stepping gait
- vision compensates
- more unsteady dark or dull situations
What are some neurological conditions associated with sensory ataxia?
- spinal cord tumours
- damage to dorsal root ganglion (Tabes Dorsalis)
- neuropathy
- multiple sclerosis
What is cerebellar ataxia?
poor synergistic activity between muscles resulting in lack of fine tuning
What are signs of cerebellar ataxia?
- problems initiating, programming and controlling multi-joint movement
- lesions in cerebellum or aff/efferent connections
- staggering or stumbling gait
- other symptoms
What are the symptoms of cerebellar ataxia?
- Dysmetria
- Dysdiadochokinesia
- Dyssynergia
- Action, intention & postural tremor
- Hypotonia
- Weakness & fatigue
How would you differentiate between a cerebellar and sensory ataxia?
Romberg test
- ability use proprioceptive info for standing balance
- sharpened Romberg with one foot Infront of other
What are Spinocerebellar Ataxias (SCA’s)?
- generally inherited
- each caused by a genetic mutation
- autosomal dominant (only need one parent have it)
- cerebellar symptoms
What is Friedrichs Ataxia?
autosomal recessive genetic disease that causes difficulty walking, loss of coordination in the arms and legs, and impaired speech that worsens over time
What are the symptoms of Friedrichs ataxia?
- dysarthria
- clumsiness
- proprioceptive loss
- spasticity
- diabetes
- poor standing balance
- scoliosis
- visual & hearing loss
- nystagmus
What is the physio treatment for Friedrichs ataxia?
- aerobic training
- bracing for scoliosis
- orthoses pes cavus
- stretches
- standing balance / gait
- transfers
What is vestibular ataxia?
is the violation of the coordination of movements and the ability to maintain a pose associated with damage to the vestibular apparatus
What is the role of the vestibular system?
- detects the position & motion of the head in space
- changes the body position in space both linear and rotational
Where does the motor output come from in the vestibular system?
- vestibulo-ocular reflex (AHC’s cranial nerves)
- vestibulo-spinal reflex (AHC’s spinal cord)
What is the peripheral vestibular system?
- Ampulla @ end each SCC contain cristae
- hair cells respond to angular acceleration
- Otolith organs (utricle & saccule)
- Otoconia allows sense linear acceleration
What does the vestibulo-ocular reflex (VOR) do?
Moves eyes right by processing info from both vestibular nuclei
What are the symptoms of vestibular dysfunction?
- postural abnormalities
- abnormal postural response
- ataxia
- vertigo
- nystagmus
- nausea
What is the Vestibulospinal reflex (VSR)?
uses organs of the vestibular system and the skeletal muscles in order to maintain balance and posture
What tracts are involved in the supraspinal control of muscle tone?
- vestibulospinal tract (VST)
- dorsal reticulospinal tract (DRT)
- medial reticulospinal tract (MRT)
What are symptoms of vestibular ataxia?
- disturbances equilibrium standing and sitting
- staggering gait and wide BOS
- may lean backwards & towards the lesion
What is the physio treatment for vestibular ataxia?
- trunk and pelvic stability
- proximal limb joints
- manual resistance tracts
- goal directed movement
- specific mobs
How is vestibular ataxia diagnosed?
- test nystagmus
- rotation tests
- posturography
- hearing tests
- caloric tests
- Sensory Organization Test (SOT)
