1. Conditions in Occupational Therapy 5th edition Ben J
Conditions in Occupational Therapy 5th edition Ben J. Atchison and Diane Powers Dirette _____________________________________________________________________ Chapter 5: Muscular Dystrophy

2. Muscular Dystrophy (MD) Description and Definitions
One of the most prolific neuromuscular disorders
Affects muscles and/or direct nervous system control
Group of hereditary diseases that weaken the muscles, progressively
Lack or absence of structural protein dystrophin
9 identified types of MD
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3. MD Description and Definitions, cont’d
Duchenne Muscular Dystrophy (DMD)
Genetically present at birth
Symptoms may not present until 3 – 4 years old
Affects only males
X-linked condition
Mother passes affected gene onto son
DMD caused by absence or deficiency of dystrophin
Delayed motor dev, proximal weakness, & ↑ fatigue
“Valley sign” frequently present
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4. MD Description and Definitions, cont’d
Duchenne Muscular Dystrophy (DMD)
Most wheelchair dependent by 12 years-old
May have cognitive impairments
Contractures may present
Affects all voluntary skeletal muscles & cardiac / pulmonary muscles
Becker Muscular Dystrophy (BMD)
Progressive muscle weakness
Affects primarily males
X-linked
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5. MD Description and Definitions, cont’d
Becker Muscular Dystrophy (BMD)
Progressive muscle weakness
Affects primarily males
X-linked inherited condition
Production of dystrophin that is partially functional
Genetically present at birth
Onset of symptoms can vary widely from years of age
Symptoms most often appear between years of age
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6. MD Description and Definitions, cont’d
Becker Muscular Dystrophy (BMD), cont’d
Often demo delayed ambulation, “toe walking”
Muscle wasting/weakness progresses proximal to distal
Usually symmetric starting in muscles of the pelvic girdle & thighs
Eventually to the trunk and upper extremities
Facial muscles are not affected
Some men become wheelchair dependent in their 30s
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7. MD Description and Definitions, cont’d
Limb-Girdle Muscular Dystrophy (LGMD)
Autosomal recessive inheritance
Both parents carry and pass on the affected gene
10% autosomal dominant, child inherits normal gene from one parent and an affected gene from the other parent
Autosomal recessive forms display more severe symptoms with a faster decline and loss of function
Equally affects males & females
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8. MD Description and Definitions, cont’d
Limb-Girdle Muscular Dystrophy (LGMD), cont’d
Dystrophin levels are normal
No associated cognitive deficits
Progression of muscle weakness is not always symmetrical
1st affects the muscles of the pelvis and shoulders
“Waddling “ gait
Usually slow muscle wasting
Positive Gower’s sign
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9. MD Description and Definitions, cont’d
Myotonic Muscular Dystrophy (MMD)
Teen or adult onset
50% affected live beyond 50 years of age
Autosomal dominant inherited disorder
Affecting both males and females
Progression of muscle weakness is slow
Weakness / wasting begins in the face, lower legs, forearms, hands, and neck
“Locking up” of muscles common
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10. MD Description and Definitions, cont’d
Myotonic Muscular Dystrophy (MMD), cont’d
Affects gastrointestinal system, vision, heart, and/or respiratory system
30% die from cardiac complications
Cognitive impairments may be present
Facioscapulohumeral Muscular Dystrophy
Autosomal dominant inherited disorder
Affects both males & females
Onset varies, age 7 – age of 20
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11. MD Description and Definitions, cont’d
Facioscapulohumeral Muscular Dystrophy, cont’d
Early onset = more severe the symptoms and faster progression
Initially affects facial, shoulder, & upper arm muscles
Weakness begins with the facial muscles & progresses
down the body
Weakness not usually symmetrical
Winged scapula
Without cardiac complication or cognitive impairments
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12. MD Description and Definitions, cont’d
Emery-Dreifuss Muscular Dystrophy (EDMD)
Less common form of MD
X-linked recessive
Primarily affects boys by age of 10
Formation of muscle contractures before any significant muscle weakness is recognized
Muscle weakness generally symmetrical on the body
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13. MD Description and Definitions, cont’d
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14. MD Incidence and Prevalence
Affects 1 in every 5,000 people
Duchenne & Becker MD are most common types
Affects all races, ages, and genders worldwide
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MD Diagnosis
3 typical diagnostic tests
Blood work for genetic testing
Electromyography (EMG)
Muscle biopsy
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16. MD Course and Prognosis
Shortened life span for most
Cardiac & respiratory complications common
Progression can be slow to rapid depending on MD Dx
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17. MD Medical / Surgical Management
No cure or specific Tx to stop progression
Symptom management greatest impact
Primary Tx goal is maintenance of independence for as long as possible
Respiratory maintenance
Skin integrity
OT / PT
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18. MD Medical / Surgical Management, cont’d
Drug Intervention (corticosteroids)
Corticosteroids
Immunosuppressant drugs
Anticonvulsants
Contracture release
Spinal stabilization
Pacemakers
Feeding tubes
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19. MD Impact on Occupational Performance
Toileting, dressing, grooming, and bathing
Driving
Meal preparation
Daily school tasks
Maintaining employment
Playing with peers
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