TBI, cerebella ataxia

  • most common causes

    • motor vehicle accidents in young men

    • falls in older adults

  • what are the two main immediate affects from trauma

    1. cerebral haemorrhage (contusions)

    2. diffuse axonal injury

  • types of cerebral haemorrhage

    • extradural (between skull and dura)

    • subdural ( between dura and arachnoid)

    • subarachnoid (between arachnoid and pia)

    • intraparenchymal (within brain tissue)

  • pathophysiology of diffuse axonal injury

    • result of acceleration / deceleration or rotational injury

    • sheering affect on the axons

    • disruption to neurofilaments and causes cellular oedema

    • MRI usually demonstrates injury in multiple areas (diffuse)

  • pathophysiology of secondary damage (swelling affect)

    1. brain damage

    2. brain swelling

    3. swelling results in secondary intracranial inflammation

    4. rises intracranial pressure

    5. tissue hypoxia and then loop repeats

  • pathophysiology of secondary damage cardiorespiratory affect

    1. brain damage

    2. cardiorespiratory compromise

    3. swelling results in secondary intracranial inflammation

    4. rises intracranial pressure

    5. tissue hypoxia and then loop repeats

  • central perfusion pressure equation

    CPP = MAP - ICP

  • reduced CPP leads to ?

    decreased cerebral blood flow as perfusion pressure is the driving force for blood delivery to the brain

  • what is severe brain injury usually defined as

    • a coma for > 6 hours

  • Glasgow coma scale

    sum of cores from 3 domains

    • eye opening

    • best verbal

    • best motor

    score out of 15 with <8 severe

  • Glasgow outcomes scale

    1. death

    2. persistant vegitiive state

    3. severe disability

    4. moderate disability

    5. good revoery

  • post traumatic amnesia PTA definition

    defined as post injury period confusion

    characterised by inability to store new information and impaired ability to learn

    correlated with brain damage

  • how to assess if PTA has been resolved

    objectively: when patient gets 12/12 of the Westmead PTA scale 3 days in a row

    generally: when the patient is aware of their circumstances and orientated to what is going on consitently

  • neurological care for tbi patient

    • establish impact of TBI on function

    • establish baseline function

    • anticipate adverse consequences

    • D/C planning

    • retraining of neurological deficits

    • educate family and patient as able

  • TBI rehab

    • long process

    • goal directed and whole ICF focused: what impairments improve activities, what activities improve participation

  • complications include…

    • contracture

    • heterotopic ossification

    • pressure injuries

  • contracture as a complication

    • caused by inactivity, immobility, sustained abnormal postures and HO (heterotopic ossification)

    • shortening of sarcomeres leads to permanent reduction in muscle length

  • at risk muscles for contracture

    • hip and knee flexors (sitting in a wheel chair)

    • ankle plantar flexors from lying in bed

    • shoulder add, IR and elbow flexors, pronators and wrist and finger flexors

  • contracture prevention

    • mobilising joints at risk

    • serial casting with BonT-A

    • mixed evidence for splints

    • E-stimulation for very weak muscles

    • tilt table

  • heterotopic ossification

    is a pathological process where bones grow in tissues which are not normally ossified

    tends to affect proximal joints more than distal joints

Cerebellar ataxia

  • vestibulocerebellum

    influences eye movements and postural movements

    • adapts postural control for specific tasks or environments

  • spinocerebellar

    role is to compare ongoing movement with intended movement

  • spinocerebellar dysfunction

    issues with this can result in

    • hypotonia

    • reduced balance (increased AP sway)

    • ataxic gait

  • cerebrocerebellum

    involved in motor planning

    function is to co-ordinate voluntary movements , planning movements , time intervals and accurate rhytyms

  • cerebrocerebellum dysfunction

    • inco-ordinated arm movements

    • decomposition of movements

  • what side is affected with cerebellar problems …

    the same side as the lesion

  • common impairments of cerebellar ataxia are

    • ataxic gait

    • motor coordination deficits (dysdiadochokinesia (impaired rapid alternating movements))

    • reduced balance

    • hypotonia oculomotor disturbances: nystagmus, impaired smooth pursuit