DMD & SMA Flashcards
Heritability of a Disease
The proportion of variation in the phenotype attributable to variation in genetic factors among individuals
4 Bases to DNA molecules
Adenine
Thymine
Guanine
Cytosine
Definition of Genetics
the study of heredity of traits of an organism & their variations within a population – a single gene
Definition of Genomics
the study of genomes or the complete set of genetic material of an organism – interactions between genes
Definition of Epigenetics
the study of inheritable changes in the organisms caused by the modification of gene expression – biologic and environmental signals determine gene expression
Disorders of the LMN (anterior horn cells of the spinal cord and peripheral nerves)
SMA
Polio
PN palsies
CMT
GBS
CIDP
DM
Disorders of the neuromuscular junction
Myasthenia gravis
Disorders of the muscles
Muscular dystrophies
NM Diseases that also include UMN involvement
ALS
Neurologic diseases of specific areas of the CNS
MS
CB diseases
Cerebral (dementia) Diseases
PD
HD
Brain Tumors
What does DMD stand for?
Duchenne Muscular Dystrophy
DMD is what physiological difference?
Absence of dystrophin, leading to muscle breakdown
What happens with a lack of dystrophin?
- ischemic damage to muscles
- free radical damage
- calcium overload
- failure to regenerate muscle
Age of onset for DMD
~3-5 years old
Classic gait pattern for those with DMD
toe walking
wide base/stance
excessive lordosis
big arm swings
waddle
DMD course of disease lower body
- Gower’s
- Inability to stand from floor
- Inability to climb stairs
- Inability to stand from chair
- Loss of ambulation (~10 years)
DMD course of disease upper body
- Inability to reach overhead
- Inability to roll in bed
- FVC 50% and need for cough assist
- Inability to feed self
- Inability to bring hands to table
- Loss of cell phone/gaming use
DMD common comorbidities
- Pulmonary – restrictive lung disease
- Cardiac – cardiomyopathy
- Endocrine – steroid related (growth, obesity, bone health, cataracts, delayed puberty)
- Orthopedic – scoliosis, contractures, fractures
- Cognitive/Behavioral – anxiety, OCD, autism, learning differences
At what age do most boys lose ambulation? (DMD)
10-12 years old
At what age do many patients require noninvasive ventilator support at night? (DMD)
15 years old
What are the benefits of glucocorticosteroids for DMD?
Prolongs walking, supine to stand, hand to mouth function by 2 years and delays scoliosis and preserves lung function
What is standard to be examined every 6 months with DMD?
function
strength
ROM
Monitor scoliosis
North Star Ambulatory Assessment - 4 key score thresholds (DMD)
- score of 27/34 declines at 8 points/year
- score of 9, loss of ambulation within 12 mo.
- score of 13, loss of ambulation within 24 mo.
- score 18+ reassured walking for 2 years
Time for 4 Stairs - time threshold (DMD)?
> 8 seconds predictor of loss of ambulation within 6-12 months
Time to rise from floor - time threshold (DMD)?
> 30 seconds predictor of loss of ambulation within 6-12 months
Time for 10 M Run/Walk - time threshold (DMD)?
> 12 seconds predictor of loss of ambulation within 6-12 months
6 Minute Walk Test - time threshold (DMD)?
- 30 m change is clinically significantly
- <350 m at risk for losing ambulation
5 general categories for intervention (DMD)
- stretching
- strength
- breathing
- physical fitness
- equipment
Interventions for DMD’s Early Ambulatory Stage (6)
- stretching
- night splinting
- school modification 504 plan
- strength
- parent/child education
- aquatics
Interventions for DMD’s Transitional Stage (6)
- activity and respiratory exercise
- aquatic exercise
- education of school personnel and family on transfers
- home accessibility
- UE strengthing
- Post-op interventions
Interventions for DMD’s Late Non-Ambulatory Stage (6)
- equipment
- respiratory management
- aquatic exercise
- pain
- palliative care
- post-op ortho function
