Muscular Dystrophies and Spinal Muscular Atrophy Flashcards
PT role w/neuromuscular diseases
- assist in ID
- treat impairments
- activity limitations with ADs, orthotics, and interventions
- participation restrictions
Muscular Dystrophy
group of hereditary myopathies
- progressive muscle weakness, deterioration, and regeneration of muscle fibers
- muscle fibers gradually replaced by fibrous and fatty tissue
Duchenne’s Muscular Dystrophy
- one of the most prevalent/disabling
- death usually respiratory or CV insufficiency
- survival into 30s
- 1 / 3500 male births
Duchenne’s:
etiology
- recessive
- X chromosome abnormality
- results in disorder dystrophin and DAP
- dystrophin acts as anchor in intracellular lattice to enhance tensile strength
- fragility in muscle membrane during contraction and hypoxia
- early breakdown of muscle fiber plasma membrane
- CK elevated early in disease
Duchenne’s: pseudoatrophy
tissue replaced w/fatty and connective tissue
gastroc, deltoids, quads, forearm extensors
Duchenne’s Clinical Presentation
- insidious, often misdiagnosed
- early reluctance to walk/run.
- falling
- difficulty w/stairs
- toe walking
- clumsiness
- Gower’s sign
- intellectual impairment/emotional
Duchenne’s signs/symptoms
- proximal muscles weaker early
- early weakness in hip/knee extensors
- exaggerated lordosis, wide BOS, waddling gait, band contractures, heel cord contractures
- los of unassisted ambulation 9-10 y.o
Duchenne’s medical intervention
- steroids (primary trx)
- myoblast transplant
- gene therapy
- cell based replacement
- creatine
Duchenne’s: steroid therapy benefits
- prolongs walking by 3 years
- improvements in isometric UE str by 60%, LE 85%
- improved pulmonary function
- improved cog function
Duchenne’s: steroid therapy AE
- weight gain
- growth suppression
- cataracts
- osteoporosis
Duchenne’s surgical management of deformity
- muscle release for Achilles
- fasciotomy of TFL/ITB
- scoliosis stabilization
Duchenne’s evidence based tests/measures
- Northstar Ambulatory Assessment
- The Performance of Upper limb for Duchenne
- Brook Scale
- Vignos Scale
- Egen Klassifikation Scale
Duchenne’s Prognosis
- Timed functional activities closely related to muscle str and loss of ambulation
- 10 m walk/run time > 9 sec and inability to rise from floor predicts loss of ambulation within 2 years
- 10 m walk
Duchenne’s:
10m walk time > 9sec and inability to rise from floor
predicts loss of ambulation within 2 years
consider WC
Duchenne’s:
10 m walk time > 12 sec
loss of ambulation within a year
order WC
Duchenne’s: PT role
- early dx
- education, referral, family support
- prolong function
- pain control
- weight control
- B&B concerns
- sleep/respiratory concerns
Duchenne’s: prolong function
- prevent contractures/deformities
- ADs
- encourage peer/community interaction
Duchenne’s: Pain control
massage and gentle stretching appear to help w/spasms
worse in adolescence when they lose ambulation
Duchenne’s PT: infancy-preschool
- family education
- preventative ROM
- mild tightness=night splint + AFO + slant board
- aerobic conditioning and functional str
Duchenne’s PT: early school age
advocate for assistance and modifications to days in school.
- clumsiness
- difficulty w/stairs
- gait deviations
Duchenne’s early school age:
gait deviations
- increased BOS
- compensated Trendelenburg
- toe walking
- lordosis with shoulder retraction
- lack of arm swing
Duchenne’s early school age goals
- family support/edu
- obtain baseline ROM/MMT
- monitor progression
- maintain flexibility
Duchenne’s: early school age: Strength and exercise
eccentric exercise and immobilization are detrimental
graded resistance controversial
Duchenne’s key muscles
abs, hip ext/ABD, knee EXT
cycling, swimming, standing 2-3 hrs daily
Duchenne’s key muscles to stretch
gastroc, hams, TFL
1-2/day. up to 10 reps. 30-60 sec
night splints + day stretching most effective
Duchenne’s early school age respiratory function
- measure RR, chest wall excursion, coughing, secretion clearing, spirometry
- breathing exercises, inspiratory muscle training
Duchenne’s adolescent intervention
- encourage participation in ADLs
- UE ergometry
- maintain muscles for transfers
- LE ROM
- Respiratory function
- standers encouraged for walking
- bracing
- surgery
Duchenne’s adolescence:
why is the position of the spine crucial?
neutral to slightly extended best to prevent scoliosis
Duchenne’s interventions:
Adulthood
After age of 18, FVC and PEF decline
- BPAP
- neg pressure ventilators
- suctioning
- breathing exercise
- postural drainage
SMA I: Wernig-Hoffman
- often noted 1st 3 months of life
- often decreased fetal movement
- hypotonia
- difficulty feeding
- respiratory distress
- muscle wasting
- DTRs decreased/absent
- limited lifespan
SMA type I: secondary impairments
- scoliosis
- contractures
- dec respiratory capacity
- fatiguability
SMA type I: PT
- ROM
- feeding
- positioning
- respiratory care
- select developmental activities
- assistive tech
SMA type I: why is there limited use of prone
- difficulty lifting head
- inhibition of abdominal expansion and diaphragmatic depression
SMA Intermediate
- floppy
- delayed motor milestones
- diagnosed 3-6 months
- weak trunk/extremities w/atrophy
- fine extremity tremors
- may or may not learn to walk
- most need orthotics
SMA Intermediate: PT
- encourage stance
- prevent deformity
- respiratory interventions
- adapt play and writing tools
Juvenile- Kugelberg-Welander
- Diagnosed between 1 and 10
- Slowly progressive weakness, mild impairment
- Proximal muscles are usually involved first
