Lecture 2: Lower Motor Neuron Disorders Flashcards
(165 cards)
1
Q
Weakness is exclusive to …
A. UMN lesions
B. LMN lesions
C. Both A and B
A
C. Both A and B
2
Q
How does UMN sensory loss appear?
A
Adjacent Body Regions
Spinal Cord: Dermatomal Pattern
3
Q
LMN signs of sensory loss present as?
A
- Spinal nerve roots: Dermatomal pattern
- Peripheral nerve pattern
- Stocking Glove
4
Q
Cranial nerve involvement would be classified as
A. UMN
B. LMN
C. BOTH
A
B. LMN, Cranial nerves are exclusive to the peripheral nervous system. Except for Cranial nerve 2, which has its myelin sheet covered with oligodendrocytes.
5
Q
Vision, Language, Cognition, Cerebellar, Basal Ganglia, and Corticobulbar abnormalities are involved with
A. UMN
B. LMN
C. BOTH
A
A. UMN
6
Q
ALS, MG, and MD are …
A. Motor disorders
B. Sensory disorders
C. Both
A
A. Motor Disorders, No sensory involvement
7
Q
UMN’s control the body with what nerve tract?
A
LCST
Lateral Corticospinal tract
8
Q
UMNs control the face and head via what nerve tract?
A
Corticobulbar tract (CBT)
9
Q
LMN Nuclei control the body via what tract?
A
Anterior horn cell in spinal cord
10
Q
LMN Nuclei control the face and head motor via what tract?
A
Cranial nerve motor nuclei (Trigeminal, Facial, Ambiguus, Spinal Accessory, Hypoglossal)
**Reminder–CN 3, 4, and 6 are not part of the corticobulbar tract.
11
Q
Which cranial nerves are not part of the Corticobulbar tract?
A
Cranial nerves 3, 4, and 6. These nerves are responsible for eye movement
12
Q
LMN Axons controls he body via what tract?
A
Spinal nerve roots to Peripheral nerve roots
13
Q
LMN Axons control the face and head motor via what tract?
A
Cranial nerves 5, 7, 9, 10, 11, 12
Intracranial segment, extra-cranial segment
14
Q
LMN terminals controls the body motor via what tract?
A
Neuromuscular junction => Muscle
15
Q
LMN Terminals control the face and head motor via what tract?
A
Neuromuscular junction => Muscle
16
Q
What are some UMN signs for body motor involvement?
A
- Hyperreflexia
- Hypertonic
- Weakness
- (+) Babinski
- (+) Hoffmann;s
17
Q
What are some face and head motor signs for UMN Involvement?
A
Hyperreflexia (Jawjerk, gag reflex)
Weakness
18
Q
Name the Cranial Nerves I II III IV V VI VII VIII IX X XI XII
A
I Olfactory II Optic III Oculomotor IV Trochlear V Trigeminal VI Abducens VII Facial VIII Vestibulochoclear IX Glossopharyngeal X Vagus XI Spinal Accessory XII Hypoglossal
19
Q
This nerve is responsible for tongue movement
A
CN XII Hypoglossal
20
Q
This nerve is responsible for head turning
A
CN XI Spinal Accessory
21
Q
This nerve is responsible for parasympathetic to most organs, Laryngeal muscles (voice) pharyngeal muscles (swallowing) and aortic arch reflexes
A
CN X Vagus
22
Q
This nerve is responsible for pharyngeal muscles; carotid body reflexes; and salivation
A
CN IX Glossopharyngeal
23
Q
This nerve is responsible for hearing and equilibrium sense
A
CN VIII Vestibulochochlear
24
Q
This nerve is responsible for muscles of facial expression, taste, lacrimation, and salivation
A
CN VII Facial
25
This nerve is responsible for eye movements
CN III, IV, VI
26
This nerve is responsible for facial sensation; and muscles of mastication
CN V Trigeminal
27
This nerve is responsible for eye movements and pupil constriction
CN III Oculomotor
28
This nerve is responsible for scent/Olfaction
CN I Olfactory N
29
Classification of the four types of motor unit disorders is based on the part of the motor unit that is affected. What are the 4 regions?
1. Primary muscle disease (Myopathies)
2. Diseases of the Neuromuscular Junction
3. Peripheral neuropathies (Axon and Myelin)
4. Motor Neuron Disease (Cell Body)
30
Motor neuron diseases can be acquired of inherited.
Polio is an example of an?
Acquired infectious disease
31
Motor neuron diseases can be acquired of inherited.
Polymyositis is an example of an?
Acquired Autoimmune disease
32
Motor neuron diseases can be acquired of inherited.
ALS and PLS are examples of an?
Acquired Idopathic Disease
33
Motor neuron diseases can be acquired of inherited.
SMA is an example of?
Inherited LMN Disease
34
Motor neuron diseases can be acquired of inherited.
Hereditary spastic paraparesis is an example of?
Inherited UMN Disease
35
Motor neuron diseases can be acquired of inherited.
Familial ALS is an example of?
Inherited UMN and LMN Disease
36
ALS Stands for
A-Myo-Tropic Lateral Sclerosis
37
Breaking down Amyotropic lateral sclerosis.
```
A:
Myo:
Tropic:
Lateral:
Sclerosis:
```
-A: Means no or negative
-Myo: Refers to muscle
-Trophic: means nourishment
(No Muscle Nourishment)
Lateral: Is the area in the spine where the brain tells the muscles what to do
Sclerosis: Is hardening as the disease progresses. The lateral areas harden and the signals stop.
38
This is the most common adult motor neuron disease
ALS
39
What is the prevalence of ALS?
1-2 per 100,000 people
40
How many cases of ALS are documented in the US per year?
5000
41
Male to female ratio of ALS?
1.5 Males : 1 Female
42
2/3 of ALS patients experience
A. Spinal onset
B. Bulbar Onset
C. Both
A. Spinal Onset
43
1/3 of ALS patients experience
A. Spinal Onset
B. Bulbar Onset
C. Both
B. Bulbar Onset
44
What is true about the etiology of ALS?
Mostly unknown.
Sporadic/Unknown cause
45
What is the mean age of Developing ALS sporadically/unknown?
60 years
46
What percent of ALS patients acquire the disease genetically?
what is the age of onset?
5%
40 years
47
What are the 6 contributing factors that lead to ALS?
1. SOD1 Mutations
2. Oxidative Damage
3. Aggregated Proteins
4. Abnormal Mitochondria
5. Excitoxicity
6. TDP-43 Abnormal Astroglia
48
With ALS, what happens to the motor neuron?
Degeneration. Damage to motor neuron cell body in the Spinalcord/Brainstem/cortex
49
With ALS, what damages the motor axon?
Wallerian Degeneration
50
With ALS, some nuclei are usually spared, these include?
1. Oculomotor
2. Trochlear
3. Abducens
4. Nucleus of Onuf (Bowel And Bladder)
51
ALS is
A. Insidious
B. Known cause
C. Stable
A. Insidious
52
Describe the disease course of ALS
1. Subtle signs: Loss of dexterity, stiffness, cramps, fatigue.
2. Weakness, Slurred Speech, Atrophy, Spasticity
3. Speech, swallowing, respiration involved
4. Dependent for mobility and ADL's
5. AVG 3-5 year progression to death.
53
ALS presents with
A. UMN signs
B. LMN signs
C. Both
C. UMN and LMN signs
54
Between UMN and LMN involvement with ASL, what is spared from the disease?
1. Extra ocular muscles
2. Cognitive function
3. Sensory Function
4. Bowel and Bladder
55
Describe the Spinal form onset of ALS? 2/3 of cases
1. Limb Onset
2. Starts distally or proximally
3. Usually asymmetrical early on
56
Describe the onset of bulbar form ALS
1. Dysarthria and dysphagia
| 2. Simultaneous limb symptoms
57
This disease is a combination of UMN and LMN signs, typically asymmetric early on.
ALS
58
What are the spared components to ALS disease?
1. Extraocular
2. Cognitive
3. Sensory
4. Bowl/Bladder
59
What type of imaging would you get for ALS diagnosis?
MRI: R/O cortical, Brainstem, or cervical spine pathology
60
Why would you order lumbar puncture diagnosis for a patient with ALS?
To rule out Inflammatory causes
61
Why would you order a blood test for a patient with ALS?
R/O Toxic, metabolic, infections, inflammatory, and genetic causes
62
What are the 2 categories of testing with ENMG (Electroneuromyography)
NCV: Nerve conduction velocity
EMG: Electromyography
63
Why would you order NCV tests for a patient with ALS?
1. To test for "Decreased compound motor unit action potential (CMAP)
2. To test for "Normal or slow nerve conduction velocity (NCV)
64
During the acute phases of ALS, what is true of a nerve conduction velocity study?
Early on, the results might be normal. Need to wait for later progression of the disease to determine NCV.
65
Why would you order an EMG for a patient with ALS Disease? (3)
To look for...
1. Fibrillations and (+) Sharp Waves
2. Fasciculations
3. Interference pattern reduced (Partial or Sparse)
66
ALS is a UMN or LMN Disorder?
Both
67
Key differential diagnosis for ALS,
UMN/LMN Disorders:
UMN Disorders:
LMN Disorders:
UMN/LMN Disorders: Brainstem/Spinal cord
UMN Disorders: Hereditary Disorders
LMN Disorders: Neuropathies/Myopathies
68
What is the only FDA approved medicine for medical management of ALS?
Riluzole: 100mg/day
69
For patients with ALS, what are the symptomatic managements?
1. Sialorrhea (Excessive salivation)
2. Muscle cramps
3. Spasticity
4. Dyspnea
5. Depression
70
For patients with ALS, What medical management must be considered for swallowing?
1. Food modification
| 2. PEG: Percutaneous endoscopic gastrostomy tube
71
For patients with ALS, what form of respiratory care is needed for them?
1. Mechanical Ventilation
| 2. Pulmonary Function Tests
72
Which form of ALS has a death rate within 2-3 years from respiratory failure?
A. Spinal form
B. Bulbar Form
C. Both
B. Bulbar Form 2-3 years till death
73
Which form of ALS has a death rate due to respiratory failure at 3-5 years?
A. Spinal form
B. Bulbar Form
C. Both
A. Spinal form 3-5 years
74
What percent of patients with ALS life greater than 10 years?
10%
75
What are the prognostic indicators for ALS disease?
1. Younger onset => Longer Duration
| 2. Early respiratory dysfunction => Poor Prognosis
76
Clinical Management
What do you want to look for with a patient who may be presenting with ALS?
(5)
1. UMN and LMN signs
2. Sensory system intact
3. No Bowl/Bladder Involvement
4. Cognitive function still intact.
5. Respiratory complications
77
Clinical Management
What are the 4 ays therapists can intervene with a patient who presents with ALS?
1. Explain the Psychological benefits associated with exercise
2. Energy conservation and safety
3. Caregiver training
4. Equipment
78
There are 4 distinct neuroanatomical regions of the muscle fibers and the motor unit attached to it.
Motor neuron diseases effect the _____________
Peripheral neuropathies effect the ____________
Diseases of the post/pre synaptic cleft effect the ____________
Diseases that effect the muscles are known as ____________
Motor neuron diseases effect the Cell Body
Peripheral neuropathies effect the Axon and Myelin
Disease of the Post/pre synaptic cleft effect the NMJ
Diseases that effect the muscles are known as Myopathies
79
Myasthenia Gravis is a disorder that effects what region of the muscle?
The Neuromuscular Junction
80
What is the most common neuromuscular junction disorder?
Myasthenia Gravis
81
How many people develop Myasthenia Gravis?
1 in 10,000-20,000 people
82
What age are women more commonly effected by Myasthenia Gravis?
20-30 years of age
83
What age of men more commonly effected by Myasthenia Gravis?
50-60 years of age
84
Myasthenia Gravis an ... disease
A. Acquired
B. Inherited
C. Both
Acquired disease
85
What is the etiology of Myasthenia Gravis disease?
Acquired Antibody-Mediated Autoimmune disease
86
Myasthenia Gravis is an acquired antibody-mediated autoimmune disease. What percentage of people have ...
Nicotonic Acetylcholine Receptor (AChR) antibodies?
90%
87
Myasthenia Gravis is an acquired antibody-mediated autoimmune disease. What percentage of people have...
AChR antibodies in the ocular form?
50%
88
What happens at the synaptic cleft with Myasthenia Gravis?
Post-synaptic receptor
Damage to the membrane
89
What is happening at the synaptic cleft that is inhibiting the binding of Acetylcholine to the Acetylcholine receptors?
AChR Antibodies are binding to the ACh receptors, inhibiting the connection of ACh Neurotransmitters to the receptors.
90
What is true of the disease course for Myasthenia Gravis?
1. Insidious
2. Slowly progressive initially and then stable
3. May include episodic exacerbations and remissions.
91
Describe the disease course of Myasthenia Gravis
1. Subtle Onset
2. Potential exacerbation with illness, pregnancy
3. Fluctuating weakness and fatiguability with full body involvement within one year
4. Progression to maximum severity in first 2 years.
92
What is the general pattern of weakness for Myasthenia Gravis?
Proximal to Distal
Arms > Legs
Quads, Triceps, and Neck extensors more
93
What are 6 contributing factors for fluctuating fatigue in patients with Myasthenia Gravis?
1. Ptosis
2. Diploplia
3. Dysarthria
4. Dysphagia
5. Respiratory Weakness
6. Limb Weakness
94
What is the pattern and Spreading of Weakness for AChR MG?
Head to Lower extremities
95
What is the Pattern and Spreading of weakness for MuSK MG?
Thoracic region down to lower extremity
96
What is the pattern and Spreading of weakness for LEMS?
Thighs to upper extremities
97
What are the 4 diagnostic tests to rule in/out Myasthenia Gravis?
1. Tensilon
2. Serologic Testing
3. Slow repetitive nerve stimulation
4. CT/MRI
98
What are we looking for with a Tensilon test for Myasthenia Gravis?
1. Positive Tensilon Test (A person is positive if after the injection, they are able to produce stronger muscle contractions) (This is preventing the breakdown of the chemical acetylcholine)
2. Clinicall response within 30-60 seconds
3. High sensitivity, Not specific to MG
4. Risk: Cardiac Side Effect
99
This drug is for patients with Myasthenia Gravis and it increases the concentration of Ach at the receptor.
Cholinesterase
100
What are the side effects associated with Cholinesterase Inhibitors?
1. Muscarinic
| 2. Nicotinic
101
This is a side effect from Cholinesterase Inhibitors that causes diarrhea, cramping, and excessive secretions
Muscarinic
102
This is a side effect from Cholinesterase Inhibitors that causes muscle fasciculations, and cholinergic crisis
Nicotinic
103
What is a short term medical management for Myasthenia Gravis?
1. Plasmapheresis
| 2. IVIG
104
What are the benefits of taking Plasmapheresis and IVIG with Myasthenia Gravis?
1. Clinical improvement within first week
2. Benefits last for 1-2 months
3. Complications uncommon
4. Primarily used during Myasthenia crisis or to stabilize a patient prior to Thymectomy
105
This is a medical management protocol for patients with Myasthenia Gravis to treat thymectomy
Immunosuppressive Corticosteroids
106
What is the prognosis with Myasthenia Gravis?
80% of patients with focal disease eventually develop generalized MG
107
Within _______ years of onset for Myasthenia Gravis, progression to maximal severity occurs
2 years
108
Patients with Myasthenia Gravis with __________ have more aggressive disease course
Thymomas
109
What is the lifespan of a patient with Myasthenia Gravis?
Normal life span
110
What are the side effects associated with Myasthenia Gravis?
1. Decreased quality of life
- Limited efficacy and side effects of medication
- Non-medicinal treatment
111
Clinical management of Myasthenia Gravis
What are we trying to identify with the disease and clinicians?
Look for signs and symptoms
1. Fluctuating and Fatiguable weakness
2. Proximal > distal weakness
3. UE > LE
- Triceps, Quadriceps, neck extensors
4. Bilateral asymmetric ocular muscle weakness
- Pupillary sparing
5. Nasal quality in voice
112
With Myasthenia Gravis, how does the weakness generally present?
Proximal Greater than Distal Weakness
113
With Myasthenia Gravis, is the UE or LE more effected?
UE effected > LE
114
What are the major muscles mainly effected by Myasthenia Gravis? (3)
1. Triceps
2. Quadriceps
3. Neck Extensors
115
What is true of the ocular muscles with Myasthenia Gravis?
Bilateral Asymmetric Ocular muscle weakness
116
What the ocular Bilateral asymmetric muscle weakness associated with Myasthenia Gravis, what is spared?
Pupillary function
117
What happens to an individuals voice with Myasthenia Gravis?
Nasal Quality of voice is noticed
118
Clinical Management of Myasthenia Gravis.
What are 2 things clinicians should be mindful of when working with these patients with respect to intervention?
1. Consider Fatigue
| 2. Energy Conservation/Modification of tasks
119
This is a Disorder with primary structural or functional impairments of the muscles.
Myopathy
120
What are the signs and symptoms associated with Myopathy? (4)
Muscle weakness and Fatigability
1. Generally proximal greater than Distal
2. Low Tone
3. Atrophy
4. Pseudo Hypertrophy
121
What is true about the sensation of a patient with Myopathy?
Sensation is intact
122
What is true of sphincter function with Myopathy?
Normal Sphincter function
123
What are the two ways someone can get Myopathy?
1. Heredity
| 2. Acquired
124
For the hereditary development of Myopathy, what are the (5) different ways?
1. Congenital Myopathies
2. Muscular dystrophies
3. Myotonias & Channelopathies
4. Primary metabolic myopathies
5. Mitochondrial Myopathies
125
For the acquired development of myopathy, what are the 5 ways individuals can attain this?
1. Inflammatory myopathies
2. Drug-induced and toxic
3. Secondary metabolic myopathies
4. Endocrine Myopathies
5. Infectious myopathies
126
What is the gold standard for assessing Myopathies?
Muscle Biopsy (Gold Standard for Myopathy)
127
What is the most common and severe form of childhood muscular dystrophy?
Duchenne Muscular Dystrophy
128
What is the proportion of children born with Duchenne's muscular dystrophy?
1 in 3,500 male births
129
What is the etiology of Duchenne's muscular dystrophy
1. Hereditary disease
X-Linked Recessive
30% spontaneous mutation
130
What is the pathogenesis of Duchenne's muscular dystrophy?
1. Slowly progressive muscular weakness with histologic abnormalities
2. Fibrosis, degeneration and regeneration of muscle, Proliferation of fatty and connective tissue
3. Decrease in Dystrophin
131
Patient's who suffer from Duchenne's muscular dystrophy have a decrease in __________
Dystrophin
132
What is the disease course of Duchenne's Muscular dystrophy?
1. Insidious
| 2. Slowly progressive weakness
133
Describe the disease course for Duchenne's Muscular Dystrophy
Insidious, slowly progressive weakness
1. Normal At birth
2. Delayed motor milestones after 1 year
3. 3-7 years old: Toe walking, towers maneuver, lordosis, scoliosis
4. 7-12 years old: Lose ability to walk
5. 20 years old: Death from fatty infiltration of heart and respiratory infections
134
What are the clinical findings associated with Duchenne's muscular dystrophy? (3)
1. Proximal weakness > Distal
2. Pseudohypertophy of the calves
3. Gower's maneuver
135
Children with Duchenne's muscular dystrophy experience what with respect to the musculature/ cardiovascular endurance
Easy Fatigability
136
As Duchenne's muscular dystrophy progresses, what clinical findings can be seen in the child? (7)
1. Contracture
2. Scoliosis/Lordosis
3. Obesity
4. Decreased Respiratory capacity
5. Cognitive Defects
6. Cardiac Dysfunction
7. GI Dysfunction
137
When diagnosing Duchenne's muscular dystrophy, what clinical examination can a PT perform?
Assess for Progressive muscle weakness
| -(Gower's sign, excessive lordosis)
138
When diagnosing Duchenne's muscular dystrophy, what 4 diagnostic tests can be performed?
1. Clinical examination looking for progressive muscle weakness
2. Serum Enzyme levels: Elevated Creatine Kinase (50-100x normal values)
3. Muscle Biopsy: looking for variation in size of muscle fibers, fat and connective tissue deposits, and dystrophin reducing or absence
4. Genetic Testing: Defect in Dystrophin gene (on Chromosome Xp21)
139
What is the medical management protocol with a patient suffering from Duchenne's muscular dystrophy? (4)
Achieve and maintain a higher quality of life than expected for the disease process
1. Slowing rate of progression
2. Preventing/minimizing contracture and deformity
3. Maintaining function and participation in spite of disease progression
4. Need to allow compensations for function while protecting against secondary impairments that may result from compensation.
140
With Duchenne's muscular dystrophy, what 3 medical management protocols must be performed to promote longevity of life?
1. Pharmaceutical intervention to slow strength decline (Prednisone 0.75mg/kg/day-prolongs ambulation up to 3 years)
2. Maximizing cardiopulmonary function as disease progresses (Prevent pulmonary infections, secretion management, airway clearance, manage scoliosis, monitor cardiac function closely)
3. Psychosocial and emotional support
141
At what age do patients with Duchenne's muscular dystrophy usually pass away?
Typically in 20's
142
Why causes termination of life with Duchenne's muscular dystrophy?
1. Fatty Infiltration of heart and respiratory infections
| 2. Improving mortality with advances in medical management (more now surviving into 30's)
143
At what age are those with Duchenne's muscular dystrophy usually prescribed a wheelchair?
12 years of age
144
Clinical Management of Duchenne's muscular dystrophy
What are 5 indications of Duchenne's muscular dystrophy?
1. Progressive weakness
2. Young Male
3. Muscle atrophy with calf (Pseudohypertophy)
4. Gowers maneuver, Sway back posture
5. Unable to perform age appropriate motor skills (climbing, running, jumping)
145
What are the 3 main interventions PT's can perform with a patient who presents with Duchenne's muscular dystrophy?
1. Encourage: Assistive technology/orthotic as needed to increase function
2. Discourage: Resistive and Eccentric exercises
3. Stretching: Daily w/standing programs
146
ALS, MG, and MD, are all __________ disorders with key presenting sign of ____________
Motor Disorders
Weakness
147
Which motor disorder includes UMN and LMN complications?
ALS
148
What is the Etiology for ALS?
95% Unknown
| 5% Hereditary
149
What is the age onset for ALS?
Mean age: 60 years
150
What are the signs and symptoms associated with ALS? (4)
1. UMN and LMN Signs
2. Intact Sensation
3. Intact Cognition
4. Intact Bowel and Bladder Function
151
What diagnostic tests are best for ALS? (4)
1. EMG
2. MRI
3. Lumbar Puncture
4. Blood Tests
152
What is the progression of ALS?
Spinal?
Bulbar?
Spinal: Limb Onset
Bulbar:
-Dysarthria (Difficult or unclear articulation of speech that is otherwise linguistically normal)
-Dysphagia (Difficulty or discomfort in swallowing)
153
What is the typical lifespan of a patient with ALS
Spinal?
Bulbar?
Spinal: 3-5 years till death
Bulbar: 2-3 years till death
154
What is the Etiology of Myasthenia Gravis?
Autoimmune disorder
155
What is the Age of onset for Myasthenia Gravis?
Male?
Female?
Male: 50-60s
Female: 20-30s
156
What are the sings and symptoms associated with Myasthenia Gravis? (5)
1. Fluctuating and Fatigable weakness
2.
- Ptosis (Drooping or falling of the upper eye lid)
- Dysarthria (Unclear speech)
- Dysphagia (Difficulty/painful swallowing)
3. Respiratory Weakness
4. Nasally Speech
5. Limb Weakness
- Proximal > Distal
- Quadriceps, Triceps, Neck Extensors
157
What are the key diagnostic tests to perform for Myasthenia Gravis? (4)
1. Tensilon Test (+)
2. Serologic Testing: Blood serum exam
3. Slow repetitive nerve stimulation (Single fiber EMG)
4. Ct/MRI (Thymoma Screen)
158
What is the general progression of Myasthenia Gravis? (2)
1. Focal Disease progresses to generalized
| 2. 2 Years from onset to maximal severity
159
What is the lifespan associated with one who has Myasthenia Gravis?
Normal
| -Decreased Quality of life
160
What is the etiology of Duchenne's muscular dystrophy?
Hereditary
161
What is the age of onset for Duchenne's muscular dystrophy?
Primarily males
| -First signs after 1 year
162
What are the clinical signs and symptoms associated with Duchenne's muscular dystrophy?(8)
1. Delayed motor milestones
2. Toe walking
3. Proximal Weakness
4. Pseudohypertrophy in claves
5. Intact bowel and bladder
6. Lordosis
7. Gowers maneuver
8. Intact Sensation
163
What are the key diagnostic tests to perform with one who has Duchenne's muscular dystrophy? (3)
1. CK Levels
2. Muscular Biopsy (Gold Standard)
3. Genetic Testing
164
What is the general progression of Duchenne's Muscular Dystrophy?
3-7 years old: Toe walking
7-12 years old: Transition to wheelchair
165
What is the lifespan of an individual with Duchenne's muscular dystrophy?
Death around 20 years old
