Neuro Peds - 03 - Other Genetic Disorders Flashcards
What is the leading cause of inherited mental retardation?
Fragile X syndrome is the leading inherited cause of mental retardation (p. 210).
When one parent is a carrier for CF, what chance does each child have of being affected?
When one parent is a carrier for CF, the child has a 50% chance of being a carrier
What genetic disorder produces muscle weakness without cognitive impairment?
Spinal Muscular Atrophy (SMA)
normal intelligence
What are the three mechanisms by which chromosome abnormalities occur?
- Nondisjunction – cells divide unequally
- Deletion – part or all of a chromosome is lost
- Translocation – part of one chromosome becomes detached and reattaches to a different chromosome
What are the two most common clinical features in children with most genetic disorders involving the central nervous system?
hypotonia
mental retardation
What principles of motor learning are important to use when working with children with cognitive impairment?
practice and repetition (the child with cognitive impairment takes longer to learn)
Also, breaking the task down into component parts improves the potential for learning the original task and for that task to carry over into other skills.
What types of interventions are appropriate for a child with low tone?
- Weight bearing/Approximation – for stability and preparation for movement, postural alignment
- Movement transition – practice active trunk rotation, postural alignment, postural control against gravity
- Trunk extension, protective extension, balance reactions – for postural control against gravity
- Walking/Gait training with postural supports - to encourage mobility
Name some secondary complications for children with low tone.
contractures
deformities
chest wall tightness
inefficient diaphragm
What interventions can be used to prevent secondary complications in children with low tone?
interventions that work towards: normal alignment maintenance of range of motion typical weight bearing postural control general mobility
For example, facilitate normal postural alignment with use of splints to prevent hyperextension or facilitate upright posture to assist gravity to help the diaphragm form correctly.
What interventions are most often used with a child with OI?
- Handling and positioning: Education of caregivers to pad all hard surfaces. They should carry the child on a pillow or in custom carrier, employ protective positioning, avoid pull-to-sit or grasping at ankles, ribs or shoulders. Employ positioning to avoid joint deformity
- Range of motion and strengthening: protected weight bearing, range of motion in straight plane, aquatic therapy – support limbs and encourage deep breathing
- Functional activities and gait: use safe, lightweight toys for motivation; encourage reaching; sitting in erect alignment (skip prop sitting) and sitting positions to being weight-bearing for LE; standing with sufficient support to avoid bending and bowing of LE long bones.
Above all, any interventions must be performed with an eye towards avoiding/preventing fracture.
What physical therapy goal is most important when working with a child with a progressive genetic disorder?
keyword - progressive
keep the family Educated and Supported throughout child’s lifetime
describe Rett Syndrome
x-linked mutation in x-linked binding protein methyl-CpG-2 ataxia mental retardation growth retardation almost always girls affected
hypotonia at birth
hypertonia and loss of acquired skills later
stereotypical hand movements - flapping, wringing, slapping, (and mouthing)
describe Osteogenesis Imperfecta
OI
Autosomal Domininant
bone metabolism
normal cognition
4 types
I - mildest - mild to moderate fragility
II - most severe, lethal - in utero fractures
III - intermediate - progressive
IV - more severe than type I - moderately severe fragility
describe Arthrogryposis Multiplex Congenita
AMC
chormosome 5 or autosomal domininant on chromosome 9
multiple joint contractures, misaligned joints
normal cognition
describe Cystic Fibrosis
CF autosomal recessive chromosome 7 defect in exocrine glands; thick mucus normal cognition
postural drainage
- retained secretions
- impaired ability to clear airways
- impaired exercise tolerance
- chest wall deformities
- nutritional deficits
describe Cri-u-chat Syndrome
chromosome 5 (short arm deleted) nervous system and mental retardation - delayed psychomotor development - hypotonia - delayed development of postural reactions - hyperextensible joints - contractures, skeletal deformities - impaired respiratory function
describe Prader-Willi Syndrome
PWS chromosome 15 (partial deletion) prior to 2 years - won't eat after 2 years - no full button obesity, underdeveloped gonads, short stature, hypotonia mild-moderate mental retardation impaired respiratory function
instill good eating habits
describe Spinal Muscular Atrophy
SMA autosomal recessive chromosome 5 (mutation) Progressive normal intelligence
3 types
- Werdnig-Hoffman - infantile SMA
- Type II - chronic or intermediate from of W-H - Chronic Childhood SMA - onset 2-18 mos
- Kugelberg-Welander - onset 2-15 years
PNS hypotonia
poor respiratory function
trunk muscle weakness
deformities
describe Phenylketonuria
autosomal recessive
inborn error of metabolism - missing enzyme
preventable
- if not prevented, mental and physical developmental delays
describe Fragile-X Syndrome
Martin-Bell Syndrome
leading cause of inherited mental retardation
mental retardation unusual facies - long, narrow face with prominent forehead, jaw, ears poor coordination generralized decrease in muscle tone enlarged tested in boys (after puberty)
joint hypermobility flatfoot inguinal hernia pectus excvatum mitral valve prolapse
define Mental Retardation
a substantial limitation in present function characterized by subaverage intelligence and related limitations in tow or more of the following areas: communication self-care home living social skills community use health and safety academics leisure work
IQ less than 70-75
What signs or symptoms would indicate respiratory or musculoskeletal deterioration in a child with DMD?
• Some signs of musculoskeletal deterioration include:
o The child develops severe lordosis, compensating for weakness of the quadriceps
o The child’s gate becomes lurching, and if the ankles do not have sufficient range to keep the feet plantigrade, dynamic balance becomes impaired.
o Gastrocnemius and TFL contractures
o Bilateral Trendelenburg signs would be indicative of hip abductor weakening.
• Some signs of respiratory deterioration include:
o Decreased oxygen saturation levels
o Recurrent pneumonia
o Chest wall tightness
