This document provides an overview of motor neuron disease (MND), including:
- MND is a group of conditions that cause motor neurons in the brain and spinal cord to degenerate, affecting movement, speaking, swallowing and breathing.
- There are two types of motor neurons - upper motor neurons in the brain and lower motor neurons in the spinal cord.
- Common types of MND include amyotrophic lateral sclerosis (ALS), primary lateral sclerosis, progressive bulbar palsy, progressive muscular atrophy, and spinal muscular atrophy.
- Symptoms vary but can include muscle weakness, wasting, spasticity, and difficulties with speech, swallowing and breathing. Current treatment focuses on
1. Motor Neuron Disease
Dechasa Imiru, MSc PT
Physiotherapy Department
Institutes of Health
Jimma University
June, 2023
2. Rehearsal
Motor neurons are cells in the brain and spinal
cord that allow us to move, speak, swallow
and breathe by sending commands from the brain to the
muscles that carry out these functions.
Their nerve fibers are the longest in the body, a single
axon can stretch from the base of the spinal cord all the
way to the toes.
3.
4. Two types of motor neurons:
Lower motor neurons
– these are neurons that
travel from the spinal cord to
the body’s muscles.
Upper motor neurons
– these are neurons that
travel between the brain and
the spinal cord
5. Upper Motor Neurons
Located in either the brain’s
motor cortex or the
brainstem.
Initiate voluntary movement
throughout the body by
connecting the cerebral
cortex to the brain stem and
spinal cord.
There are a few tracts, or
pathways that UMNs can travel,
which serve different functions:
pyramid,
extrapyramidal,
rubrospinal,
tectospinal, and
reticulospinal tracts.
6. Lower Motor Neurons
Located in the spinal cord, are responsible for
communicating signals to the skeletal muscles,
organs, and glands.
They receive information from the UMNs, either
directly or via interneurons, and stimulate their
activity, extending their fibers to their appropriate
destinations.
Somatic motor neurons can be divided into alpha,
beta, and gamma motor neurons.
7. Introduction
The motor neurone diseases (MND) are a group of
neurological disorders that selectively affect motor
neurones.
group of conditions that cause the nerves in the spinal
cord and brain to progressively lose function.
They are generally progressive in nature, and can cause
progressive disability and mortality.
8. CONT….
MNDs are a set of chronic, degenerative, and
progressive neurological conditions typified by the
destruction of motor neurons and the subsequent
deterioration of voluntary muscle activity. such as:
Walking
Breathing
Speaking
Swallowing.
9. Cont.…
They are a rare but serious and incurable form of
progressive neurodegeneration.
MND can affect how you walk, talk, eat, drink and
breath.
Some people also experience changes to their thinking
and behavior.
10. Cont.….
However, MND affects everyone differently.
Not all symptoms will affect everyone, or in the same
order.
Symptoms also progress at varying speeds, which makes
the course of the disease difficult to predict.
11. Etiologies
It is still not possible to give a clear answer about the
causes of MND.
Some MNDs are inherited, but the causes of most MNDs
are not known.
In sporadic MNDs, environmental, toxic, viral, and/or
genetic factors may play a role in the development of
the disease.
12. Epidemiology
The incidence of MND is approximately 1-3 out of
100,000 people.
Men have a slightly higher incidence rate than women.
Age is the greatest risk factor, with symptoms typically
presenting between the ages of 50-70.
Cases under the age of 50 years are called "young onset
MND".
13. Cont.…
It can appear at any age, but most patients are over 40
years old at diagnosis.
It can significantly shorten life expectancy, but some
people live with it for many years.
There are treatments that can reduce the impact it has on
your daily life.
14. How are they classified?
MNDs are classified according to whether the loss
of function (degeneration)
• Inherited (passed down through family genetics)
• Sporadic (no family history)
• Affects the upper motor neurons, lower motor neurons,
or both.
16. Amyotrophic lateral sclerosis (ALS)
The most common type in adults, affects both UMNs and LMNs
Spastic paralysis, hyper reflex in LL ,
Flaccid paralysis, Decrease reflex in UL.
Slurred speech, difficult in swallowing and breathing in later stages
90% sporadic , 10% inherited .
Most people with ALS die from respiratory failure.
Mean survival time is 3 to 5 years, but some people live 10 years
or more.
17. Primary lateral sclerosis (PLS)
Affects only the upper motor neurons.
The legs and arms become stiff, clumsy, slow, and weak, making it
difficult to walk and fine hand coordination.
Speech may become slowed and slurred.
have difficultly balancing, increasing the risk of falls.
Progress slowly- not usually fatal.
Some PLS patients develop lower motor disease =ALS
18. Progressive bulbar palsy (PBP)
Affected LMNs of the brain stem are most affected.
People with ALS often have PBP too.
The condition causes frequent choking, difficulty
speaking, eating, and swallowing.
Mildly abnormal signs in the arms and legs.
19. Progressive muscular atrophy (PMA):
A rare disease and affects only LMNs in the spinal cord.
Weakness is typically seen first in the hands and then spreads into
the lower body,
Muscle wasting (shrinking), clumsy hand movements, twitches,
and muscle cramps. Breathing may become impaired.
Exposure to cold can worsen symptoms.
It may be a variation of ALS.
20. Spinal muscular atrophy (SMA):
An inherited/genetic MND that affects children.
Affects lower motor neurons.
Defects in the SMN1 gene result in a loss of the SMN
protein.
Low levels of the SMN protein cause lower motor
neurons to deteriorate.
producing muscle weakness and wasting.
weakness is often worse in the proximal muscles.
22. General sign and symptom
Progressive weakness
Unilateral muscle wasting in the hands
Muscle fasciculation
Spasticity or stiffness in the arms and legs
Overactive tendon reflexes
Dragging foot
Muscle wasting
Slurred speech, swallowing and breathing problem.
23. Diagnosis
The diagnosis of MND is on the basis of history and
neurological examination.
Blood tests to look for a rise in a creatine kinase.
Nerve conduction studies involve recording how fast an
electrical impulse moves the nerve cell .
EMG to measure their electrical activity of muscles.
Magnetic Resonance Imagery scans.
24. Management
Currently there is no cure for MND.
The only drug that affects the course of the disease is riluzole.
The drug functions by blocking the effects of the neurotransmitter
glutamate.
Multidisciplinary teams:
• Neurology
• Physical therapy
• Speech therapy
• Respiratory therapy and social work
25. Physiotherapy Assessment
The objective assessment of the patient should
consider impairments:
Musculoskeletal
Respiratory
Nervous systems and
Functions (balance, mobility, exercise tolerance and
functioning)
26. Physiotherapy management
Treatment depends on the particular problem presented by the
patient.
The common aim of physiotherapy management are:-
Maintain proper posture
Maintaining Mobility and Function
Prevention of contractures
Preserve functional endurance capacity and gait
Cough and airway secretion management
Respiratory muscle training
Manage spasticity and muscle weakness.
27. cont.…..
Provides necessary aids to living.
Maintain independence as long as possible
Decrease the risk of fall
Pain Management
Fatigue Management
Education of Patients
28. Cont.….
Stretching and strengthening exercises.
Resistance and aerobic training
Rom exercises and joint mobilization
Weight bearing exercise With standing equipment such
as an tilt table.
Postural correction
TENS
29. Cont.…
Hydrotherapy and Heat therapy
Assistive devices and supports or braces, neck collar,
orthotics.
Balance exercise
Gait training including treadmill training
Advice and links…
30. References
• Umphred DA, Lazaro RT. Neurological rehabilitation. Elsevier Health
Sciences; 2012 Aug 14.
• Dharmadasa T, Henderson RD, Talman PS, Macdonell RA, Mathers S,
Schultz DW, Needham M, Zoing M, Vucic S, Kiernan MC. Motor
neurone disease: progress and challenges. Medical Journal of
Australia. 2017 May;206(8):357-62.
• Morris J. Amyotrophic lateral sclerosis (ALS) and related motor
neuron diseases: an overview. The Neurodiagnostic Journal. 2015 Sep
1;55(3):180-94.
• Kernich CA. Motor neuron disease. The Neurologist. 2009 Jan
1;15(1):49-50.