Motor neuron disease Flashcards
what is MND / amyotrophic lateral sclerosis ALS?
-a progressive neurodegenerative disease
-incidious onset of painless, progressive weakness
-characterised by progressive loss of motor neurons in the cortex, brain stem and spinal cord, leading to worsening paralysis of voluntary muscles
what is neuromuscular disease?
an umbrella term used to describe disease of the muscle, peripheral nerve or neuromuscular junction
describe the epidemiology of MND
-the most common neuro denegeration of young and middle aged adults
-200 people with MND in Ireland
-age of onset 47-63 years, but can occur at any age
-fatal disease
what is the median survival of MND?
-2.5-5y
what are the most common symptoms of MND initially?
-clumsy hand
-slurred speech
-shoulder weakness eg difficulty lifting
-foot drop/ tripping
-difficulty walking
-decreased endurance
what are bulbar features of MND?
-dysarthria - slurred speech
-dysphagia
-tongue
what are the different types of MND?
-amyotrophic lateral sclerosis
-progressive muscular atrophy
-progressive bulbar palsy
-primary lateral sclerosis
how is MND diagnosed?
-no single test or biomarker
-EMG - widespread denervation + conduction block
-normal sensory responses
-difficult diagnostic process
-common to have misdiagnoses along the way eg cervical or lumbar radiculopathy
what is the most common type motor neuron disease?
-amyotrophic lateral sclerosis
-66% of cases
-UMN and anterior horn cells
what are the limb features of MND?
-focal weakness
-distal weakness
-falls/ trips from foot drop
-muscle wasting- hands, shoulder, typically asymmetrical
-cramps
-muscle twitching or fasciculations
what is the el Escorial criteria for diagnosis of definite ALS
-presence of UMN and LMN signs in the bulbar region and at 2 of the other spinal regions
what factors lead better prognosis?
-limbs
-slower rate of disease progression
-no frontal temporal dementia
-access to specialist MDT
what factors lead to a worse prognosis with MND?
-bulbar or respiratory symptoms
-if the diagnostic delay is shorter
-if the rate of disease progression is faster
-if there is front-temporal dementia
what is the drug used for MND?
riluzole
-increases survival by 4.2 months
-mechanism isn’t fully understood
why is it important to have MDT management for MND?
-only comprehensive MDT care can effectively improve the QOL from diagnosis to death
-can increase the survival rate by 7.5 months and reduce the one year mortality rate by 30%
what can be done about swallowing difficulties with MND?
-SLT & dietician assessment is important
-they can modify diet and give thickened fluids etc
-RIG,PEG if appropriate - criteria needs to be met
what most frequently causes death in MND?
-respiratory failure - not due to the lungs but due to the respiratory muscles
what are symptoms of respirator impairment in ALS?
-dyspnoea on exertion or talking
-orthopnoea
-excessive day time sleepiness
-difficulty clearning secretions
-nocturia
-poor appetite
-morning headache
what are secondary problems seen in MND?
-ateltectasis
-secretion retention
-fatigue due to coughing ineffectively
-pneumonia
-disuse atrophy
-shortening of musculature
-chest wall stiffness
how are respiratory problems managed with MND?
-tracheostomy - can result in poor QOL
-NIV - based on overnight pulse oximetry, ABGS and symptoms etc
-use of meds to decrease secretion production
what are examples pf cognitive problems associated with ALS?
-impaired executive dysfunction
-impacts on management: memory, understanding, engagement
-faster rate of functional decline
what is the role of the physio with MND?
-mobility
-respiratory care
-exercise
-pain management
what things can a physio do to help with mobility for a patient with ALS?
-if foot drop present, could provide dictus splint or AFO
-gait aids could be provided
-wheelchair?
-carer
-fatigue management
what can physios do to manage respiratory issues with ALS?
-positioning
-reduce secretions and secretion retention
-positioning to a maximum mechanical advantage
-prevention of atelectasis
-manually assisted cough
-airway clearance technique
what are the ways of accessing cough with ALS patients?
use a peak cough flow
if it is less than 160l/min then it is an ineffective cough
how can we manage the weak cough as physios?
-manually assisted cough
-manually assisted cough using NIV to boost airflow
-breath stacking
-cough assist
what are the recommendations for exercise for MND / ALS?
-physical exercise interventions - aerobic, moderate to high intensity strength and endurance exercise, functional training or stretching
-intervention time from 2 weeks -6 months
what are the recommendations regarding strength exercise for ALS?
-recommended for early stage disease and ideally slowly progressive disease
-suitable for > grade 3 strength only
-best using a low intensity and resistance
what is the rationale for stretching or PROM exercises for MND?
-maintain muscle + soft tissue extensibility and prevent contractures
-PROM to joints that patients cannot move themselves
-stretching + ROM for spasticity management
-education of carers and family members on PROM
what are the 2 main sources of pain in MND?
MSK - due to muscular imbalance
spasticity - cramping
