When you are finished test, please

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When you are finished test, please

• Place green sheet on overhead
• Keep orange sheet and check answers in hallway
• Return to classroom only when everyone has
  finished the test.
• Thanks

2
BIO 301PT CHAPTER 19

• Genetic and Developmental Disorders

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CHAPTER 19 OVERVIEW

• A. Introduction to types of genetic or
  developmental disorders
• B. Terms
• C. Cerebral palsy (CP)
• D. Down syndrome
• E. Scoliosis
• F. Neural tube defects (NTD) (spina bifida)
• G. Congenital hip dysplasia (CHD)
• H. Legg-Calve-Perthes disease

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CHAPTER 19 OVERVIEW, cont.

• I. Osgood-Schlatter disease
• J. Osteogenesis perfecta
• K.Skeletal developmental problems (genu varum,
  genu valgum, tibial or femoral torsion, clubfoot
• L. Muscular dystrophy (MD)
• M. Torticollis
• N. Erbs palsy
• O. Arthrogryposis mutiplex congenita (AMC)
• P. Spinal muscular atrophy (SMA)

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EXHAUSTED ?????
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CHAPTER 19 OVERVIEW

• A. Introduction to types of genetic or
  developmental disorders
• B. Terms
• C. Cerebral palsy (CP)
• D. Down syndrome
• E. Scoliosis
• F. Neural tube defects (NTD) (spina bifida)
• G. Congenital hip dysplasia (CHD)
• H. Legg-Calve-Perthes disease

7
A. Introduction

• Frequency birth defects in 1 of 14 live births
  (and account for many still births). FAS or
  crack account for many defects.

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A. Introduction

• Frequency birth defects on 1 of 14 live births
  (and account for many still births). FAS or
  crack account for many defects.
• Congenital defects from time of birth or soon
  after

9
A. Introduction

• Frequency birth defects on 1 of 14 live births
  (and account for many still births). FAS or
  crack account for many defects.
• Congenital defects from time of birth or soon
  after
• Birth defects may be
• Hereditary due to genetic mutations. S/S may not
  manifest for years.
• Environmental (in utero, at birth, or in years
  after birth)

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HEREDITARY/ GENETIC DISORDERS

• 1. Single gene disorders Marfans, HD,
  achondroplasia, CF, PKU, sickle anemia

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HEREDITARY/ GENETIC DISORDERS

• 1. Single gene disorders Marfans, HD,
  achondroplasia, CF, PKU, sickle anemia
• 2. Multifactorial (possibly many genes
  environment) disorders

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HEREDITARY/ GENETIC DISORDERS

• 1. Single gene disorders Marfans, HD,
  achondroplasia, CF, PKU, sickle anemia
• 2. Multifactorial (possibly many genes
  environment) disorders clubfoot, congenital hip
  dysplasia, congenital heart disease,
  myelomeningocele

13
HEREDITARY/ GENETIC DISORDERS

• 1. Single gene disorders Marfans, HD,
  achondroplasia, CF, PKU, sickle anemia
• 2. Multifactorial (possibly many genes
  environment) disorders clubfoot, congenital hip
  dysplasia, congenital heart disease,
  myelomeningocele
• 3. Chromosomal disorders entire extra (or
  deficient) gene ___________ (trisomy 21)

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HEREDITARY/ GENETIC DISORDERS

• 1. Single gene disorders Marfans, HD,
  achondroplasia, CF, PKU, sickle anemia
• 2. Multifactorial (possibly many genes
  environment) disorders
• 3. Chromosomal disorders entire extra (or
  deficient) gene Down Syndrome (trisomy 21)

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HEREDITARY/ GENETIC DISORDERS

• 1. Single gene disorders Marfans, HD,
  achondroplasia, CF, PKU, sickle anemia
• 2. Multifactorial (possibly many genes
  environment) disorders
• 3. Chromosomal disorders entire extra (or
  deficient) gene Down Syndrome (trisomy 21) (or
  translocation etc. of sections of chromosomes)

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A. Introduction

• Frequency birth defects on 1 of 14 live births
  (and account for many still births). FAS or
  crack account for many defects.
• Congenital defects from time of birth or soon
  after
• Birth defects may be
• Hereditary due to genetic mutations. S/S may not
  manifest for years.
• Environmental (in utero, at birth, or in years
  after birth)

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Birth defects may be

• 1. Hereditary due to genetic mutations. S/S may
  not manifest for years.
• 2. Environmental (the babys environment) a. in
  utero for nine months

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Disorders related to developing babys
environment Mom

• Especially if embryo (0-8 weeks in gestation) is
  exposed
• Teratogens agents that cause abnormal
  development
• Radiation (such as x-rays)
• Chemicals drugs, FAS, cocaine, folic acid
  deficiency
• Infections

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Birth defects may be

• 1. Hereditary due to genetic mutations. S/S may
  not manifest for years.
• 2. Environmental (the babys environment)
• in utero for nine months
• perinatally (at time of birth peri around)
  CP.

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Birth defects may be

• 1. Hereditary due to genetic mutations. S/S may
  not manifest for years.
• 2. Environmental (the babys environment)
• in utero for nine months
• perinatally (at time of birth peri around) CP
• postnatally (immediately or at any time after
  birth)

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CHAPTER 19 OVERVIEW

• A. Introduction to types of genetic or
  developmental disorders
• B. Terms word roots an-, bifid-, -cele, cyst,
  dys-, enceph-, mening-, myelo-, occult, -plasia
• C. Cerebral palsy (CP)
• D. Down syndrome
• E. Scoliosis
• F. Neural tube defects (NTD) (spina bifida)
• G. Congenital hip dysplasia (CHD)
• H. Legg-Calve-Perthes disease

22
CHAPTER 19 OVERVIEW

• A. Introduction to types of genetic or
  developmental disorders
• B. Terms word roots an-, bifid-, -cele, cyst,
  dys-, enceph-, mening-, myelo-, occult, -plasia
• C. Cerebral palsy (CP)
• D. Down syndrome
• E. Scoliosis
• F. Neural tube defects (NTD) (spina bifida)
• G. Congenital hip dysplasia (CHD)
• H. Legg-Calve-Perthes disease

23
C. Cerebral palsy (CP)

• 1. Overview
• FYI 2-4 cases/1000 births
• Group of disorders related to lesions of cerebral
  cortex --- abnormal movements and reflexes
  some other S/S.

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C. Cerebral palsy (CP), cont.

• 1. Disorders related to lesions of cerebral
  cortex (c.c.)--- abnormal movements and reflexes
  some other S/S.
• Hypertonic spasticity (75 of cases) plegia
  paralysis. Damage to upper motorneuron (CB in
  c.c.) causes spastic paralysis.

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C. Cerebral palsy (CP), cont.

• 1. Disorders related to lesions of cerebral
  cortex --- abnormal movements and reflexes
  some other S/S.
• Hypertonic spasticity (75 of cases)
• one side only (hemiplegic),
• trunk both lower extremities (diplegic)
• one limb only (monoplegic)
• all four extremities (quadriplegic)

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C. Cerebral palsy (CP), cont.

• 1. Disorders related to lesions of cerebral
  cortex --- abnormal movements and reflexes
  some other S/S.
• Hypertonic spasticity (75 of cases)
• plegias
• Hypotonic or ataxia (uncoordinated voluntary
  movements)
• A mix hypertonic hypotonic

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C. Cerebral palsy (CP), cont.

• 1. Disorders --- abnormal movements and reflexes
  some other S/S.
• Hypertonicity
• Hypotonicity or ataxia (uncoordinated voluntary
  movements)
• A mix hypertonicity hypotonicity
• Dyskinesia, such as chorea or rigidity
• Other effects sensory losses, speech disorders,
  mental retardation, LD, incontinence of B B

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C. Cerebral palsy (CP)

• 1. Overview disorders related to lesions of
  cerebral cortex --- abnormal movements and
  reflexes some other S/S.
• 2. Etiology and pathogenesis.

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C. Cerebral palsy (CP)

• 1. Overview disorders related to lesions of
  cerebral cortex --- abnormal movements and
  reflexes some other S/S.
• 2. Etiology and pathogenesis.
• NOT hereditary
• NOT progressive (but changes with growth)

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C. Cerebral palsy (CP)

• 1. Overview disorders related to lesions of
  cerebral cortex --- abnormal movements and
  reflexes some other S/S.
• 2. Etiology and pathogenesis.
• NOT hereditary
• NOT progressive (but changes with growth)
• Etiology pre, peri-, or postnatal deprivation of
  oxygen

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OXYGEN DEFICITS (FYI)

• Anoxia lack of oxygen in inspired air (or in
  tissues, as a result)
• Hypoxia inadequate amount of oxygen in inspired
  air (as at high altitudes) or in tissues (as a
  result)

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OXYGEN DEFICITS

• Anoxia lack of oxygen in inspired air (or in
  tissues, as a result)
• Hypoxia inadequate amount of oxygen in inspired
  air (as at high altitudes) or in tissues (as a
  result)
• Hypoxemia insufficient oxygenation in blood
• Asphyxia decrease in O2 and increase in CO2
  related to respiratory problems

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Causes of cerebral hypoxia in newborns p. 579
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Causes of cerebral hypoxia in newborns p. 579
35
Causes of cerebral hypoxia in newborns p. 579
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POWER (ATP) FAILURE in HYPOXIA Enzymes
Leak
Na
K
Normal
O2
No ATP
Na H2O
O2
Cell swells
Lactic acid
Cells die/open/leak
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C. Cerebral palsy (CP)

• 1. Overview disorders related to lesions of
  cerebral cortex --- abnormal movements and
  reflexes some other S/S.
• 2. Etiology and pathogenesis.
• NOT hereditary
• NOT progressive (but changes with growth)
• Etiology pre, peri-, or postnatal deprivation of
  oxygen. Severity depends on gestational age and
  amount of oxygen deprivation.

38
C. Cerebral palsy (CP)

• 1. Lesions of c.c. --- abn movements, other S/S
• 2. Etiology and pathogenesis.
• 3. Omit details except for this info
• Dx Tx (dorsal rhizotomy, meds baclofen muscle
  relaxants for severe positioning disorders)
• Px maybe normal lifespan depends on degree
  infections may kill.
• PT implications (579) start Tx early (Sx (positioning), PROM, adaptive equipment

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CHAPTER 19 OVERVIEW

• A. Introduction to types of genetic or
  developmental disorders
• B. Terms word roots an-, bifid-, -cele, cyst,
  dys-, enceph-, mening-, myelo-, occult, -plasia
• C. Cerebral palsy (CP)
• D. Down syndrome
• E. Scoliosis
• F. Neural tube defects (NTD) (spina bifida)
• G. Congenital hip dysplasia (CHD)
• H. Legg-Calve-Perthes disease

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D. Down syndrome overview

• THE most common chromosomal disorder
• Trisomy 21 24 23 47 chromosomes in every
  cell (since all derived from first cell) sperm
  or egg brings 23 chromosomes to zygote

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D. Down syndrome

• THE most common chromosomal disorder
• Down syndrome 24 23 47 chromosomes in every
  cell (since all derived from first cell)
• Occur when sperm or egg brings 23 (or chromosomes to zygote.
• More common if mom (younger? older?)

42
D. Down syndrome overview

• THE most common chromosomal disorder
• Down syndrome 24 23 47 chromosomes in every
  cell (since all derived from first cell)
• Occur when sperm or egg brings 23 (or chromosomes to zygote.
• More common if mom older (especially 40 years)

43
D. Down syndrome

• 1. Overview, incidence
• 2. Etiology, pathogenesis trisomy 21 affects all
  body cells. Many effects (582)
• Smaller brain weight
• Cerebellum --- muscle hypotonia
• Hippocampus (memory deficits --- Alzheimers)

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D. Down syndrome S/S

• Smaller brain weight
• Cerebellum --- muscle hypotonia
• Hippocampus (memory deficits --- Alzheimers)
• Cerebrum mental retardation
• Pons respiratory problems

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D. Down syndrome S/S

• Smaller brain weight
• Cerebellum --- muscle hypotonia
• Hippocampus (memory deficits --- Alzheimers)
• Mental retardation
• Flat face/nasal bridge, protruding tongue
  breathing problems (ear, lung infections) and
  feeding/defecation problems

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D. Down syndrome S/S

• Smaller brain weight
• Cerebellum --- muscle hypotonia
• Hippocampus (memory deficits --- Alzheimers)
• Mental retardation
• Flat face/nasal bridge, protruding tongue
  breathing problems (ear, lung infections) and
  feeding/defecation problems
• Heart problems (FYI AV valves, VSD)

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D. Down syndrome S/S

• Smaller brain weight
• Cerebellum --- muscle hypotonia
• Hippocampus (memory deficits --- Alzheimers)
• Mental retardation
• Flat face/nasal bridge, protruding tongue
  breathing problems (ear, lung infections) and
  feeding/defecation problems
• Heart problems (FYI AV valves, VSD)

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D. Down syndrome S/S, cont.

• Skeletomuscular problems
• Hypotonia --- persistent hip abduction ---
  slipped capital femoral epiphysis (abnormal
  femoral head)
• Hypotonia --- delayed motor skills
• Hypotonia --- respiratory infections

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D. Down syndrome S/S, cont.

• Skeletomuscular problems
• Hypotonia --- persistent hip abduction ---
  slipped capital femoral epiphysis (abn femoral
  head)
• Hypotonia --- delayed motor skills
• Hypotonia --- respiratory infections
• Ligamentous laxity AAI C1-C2 subluxation with
  related risks to CNS
• Shorter limbs, smaller steps (altered gait)

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D. Down syndrome S/S, cont.

• Skeletomuscular problems
• Hypotonia --- persistent hip abduction ---
  slipped capital femoral epiphysis (abn femoral
  head)
• Hypotonia --- delayed motor skills
• Hypotonia --- respiratory infections
• Ligamentous laxity AAI (atlantoaxial
  instability) C1-C2 subluxation with related
  risks to CNS
• Shorter limbs, smaller steps (altered gait)

51
CHAPTER 19 OVERVIEW

• A. Introduction to types of genetic or
  developmental disorders
• B. Terms word roots an-, bifid-, -cele, cyst,
  dys-, enceph-, mening-, myelo-, occult, -plasia
• C. Cerebral palsy (CP)
• D. Down syndrome
• E. Scoliosis
• F. Neural tube defects (NTD) (spina bifida)
• G. Congenital hip dysplasia (CHD)
• H. Legg-Calve-Perthes disease

52
E1. Scoliosis

• Abnormal lateral curvature (C-, S-shaped)
• Onset and incidence
• Onset from infants to adolescents
• 1 in 10 children have some degree of scoliosis
  1/4 of these need some Tx
• Adolescents 10 1 (girls to boys)

53
E1. Scoliosis

• Abnormal lateral curvature (C-, S-shaped)
• Onset and incidence
• Categories
• Functional postural

54
E1. Scoliosis

• Abnormal lateral curvature (C-, S-shaped)
• Onset and incidence
• Categories
• Functional postural
• Structural
• Congenital faulty vertebral development in
  embryo

55
E1. Scoliosis

• Abnormal lateral curvature (C-, S-shaped)
• Incidence
• Categories
• Functional postural
• Structural
• Congenital faulty vertebral development in
  embryo
• Neuromuscular CP, DMD, muscle weakness

56
E1. Scoliosis

• Abnormal lateral curvature (C-, S-shaped)
• Incidence
• Categories
• Functional postural
• Structural
• Congenital faulty vertebral development in
  embryo
• Neuromuscular CP, DMD, muscle weakness
• Idiopathic _____________

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E1. Scoliosis

• Abnormal lateral curvature (C-, S-shaped)
• Incidence
• Categories
• Functional postural
• Structural
• Congenital faulty vertebral development in
  embryo
• Neuromuscular CP, DMD, muscle weakness
• Idiopathic no known cause.

58
E1. Scoliosis

• Abnormal lateral curvature (C-, S-shaped)
• Incidence
• Categories
• Functional postural
• Structural
• Congenital faulty vertebral development in
  embryo
• Neuromuscular CP, DMD, muscle weakness
• Idiopathic no known cause (probably genetic
  growth-related). In 75 of cases, as in teen
  girls.

59
E1. Scoliosis

• Abnormal lateral curvature (C-, S-shaped)
• Incidence
• Categories functional, structural
• Nature of most common curvature

60
Most common curvature of scoliosis T-right,
L-left
Thoracic
Lumbar
Posterior view of vertebral column
61
E1. Scoliosis

• Abnormal lateral curvature (C-, S-shaped)
• Incidence
• Categories functional, structural
• Nature of most common curvature
• Important to Tx since progressive --- decreased
  lung capacity vertebral subluxation/disk
  disease back pain/sciatica

62
E1. Scoliosis

• Abnormal lateral curvature (C-, S-shaped)
• Incidence
• Categories functional, structural
• Nature of most common curvature
• Important to Tx since progressive --- S/S
  (respiratory vertebral pain)
• Dx early to limit progression scoliometer
  (Figs. 584-585).

63
E1. Scoliosis

• Abnormal lateral curvature (C-, S-shaped)
• Incidence
• Categories functional, structural
• Nature of most common curvature
• Important to Tx since progressive --- S/S
  (respiratory vertebral, pain)
• Dx early to limit progression scoliometer
  (Figs. 584-585) usually not pain in teens. If
  so, see MD to R/O tumors, osteomyelitis.

64
E1. Scoliosis

• Abnormal lateral curvature (C-, S-shaped)
• Incidence
• Categories functional, structural
• Nature of most common curvature
• Important to Tx since progressive
• Dx early to limit progression
• PT implications (586) education, screening,
  strengthening trunk, extensors, gluteals

65
E2. Kyphoscoliosis

• Or kyphosis abnormal A-P curvature (concave
  anteriorly)
• Etiology

66
E2. Kyphoscoliosis

• Or kyphosis abnormal A-P curvature (concave
  anteriorly)
• Etiology age-related
• Adolescents re to posture or idiopathic
  (possibly due to ischemia of T vertebrae during
  growth periods)
• Elderly re to poor posture, disk degeneration,
  or osteoporosis

67
E2. Kyphoscoliosis

• Or kyphosis abnormal A-P curvature (concave
  anteriorly)
• Etiology age-related
• Adolescents re to posture or idiopathic
  (possibly due to ischemia of T vertebrae during
  growth periods)
• Elderly re to poor posture, disk degeneration,
  or osteoporosis
• Tx postural, stretching, gluteal exercises
  bracing

68
CHAPTER 19 OVERVIEW

• A. Introduction to types of genetic or
  developmental disorders
• B. Terms word roots an-, bifid-, -cele, cyst,
  dys-, enceph-, mening-, myelo-, occult, -plasia
• C. Cerebral palsy (CP)
• D. Down syndrome
• E. Scoliosis
• F. Neural tube defects (NTD) (spina bifida)
• G. Congenital hip dysplasia (CHD)
• H. Legg-Calve-Perthes disease

69
F. Neural tube defects (NTF)

• 1. THE problem neural tube fails to close.
  Spinal cord and nerves may not be covered by
  meninges and bone. Extent/severity varies.

70
F. Neural tube defects (NTF)

• 1. THE problem neural tube fails to close.
  Spinal cord and nerves may not be covered by
  meninges and bone. Extent/severity varies.
• Neural tube should close (except at the two ends)
  about day 23 of gestation.
• It may not close or may reopen due to increased
  CSF.

71
F. Neural tube defects (NTF)

• 1. THE problem neural tube fails to close.
  Spinal cord and nerves may not be covered by
  meninges and bone. Extent/severity varies.
• Neural tube should close (except at the two ends)
  about day 23 of gestation.
• It may not close or may reopen due to increased
  CSF.
• 2. Most common spina bifida

72
F. Neural tube defects (NTF)

• 1. THE problem neural tube fails to close.
  Spinal cord and nerves may not be covered by
  meninges and bone. Extent/severity varies.
• 2. Most common spina bifida
• Spina bifida occulta cord and nerves NOT exposed
  (are hidden). Minor S/S

73
F. Neural tube defects (NTF)

• 1. THE problem neural tube fails to close.
  Spinal cord and nerves may not be covered by
  meninges and bone. Extent/severity varies.
• 2. Most common spina bifida
• Spina bifida occulta cord and nerves NOT exposed
  (are hidden). Minor S/S
• (FYI term) Spina bifida cystica (aperta)
• Meningocele meninges protrude. Minor S/S.
• Myelomeningocele

74
F. Neural tube defects (NTF)

• 1. THE problem neural tube fails to close.
  Spinal cord and nerves may not be covered by
  meninges and bone. Extent/severity varies.
• 2. Most common spina bifida
• Spina bifida occulta cord and nerves NOT exposed
  (are hidden) minor S/S
• (FYI term) Spina bifida cystica
• Meningocele meninges protrude. Minor S/S.
• Myelomeningocele cord and spinal nerves DO
  protrude. Major problems.

75
F. Neural tube defects (NTF)

• 1. THE problem neural tube fails to close.
  Spinal cord and nerves may not be covered by
  meninges and bone. Extent/severity varies.
• 2. Most common spina bifida.
• Myelomeningocele cord and spinal nerves DO
  protrude. Major problems
• Permanent neuro impairment
• Hydrocephalus (in 90) bulging fontanels,
  setting sun sign, lethary or irritability (Box
  590. See shunt p. 592

76
F. Neural tube defects (NTF)

• 1. THE problem neural tube fails to close.
• 2. Most common spina bifida
• Myelomeningocele
• 3. Incidence of NTDs 1 or 2 per 1,000

77
F. Neural tube defects (NTF)

• 1. THE problem neural tube fails to close.
• 2. Most common spina bifida
• Myelomeningocele
• 3. Incidence of NTDs 1 or 2 per 1,000
• 4. Etiology
• Genetic predisposition 50X more likely if couple
  already has 1 child with sp. bifida
• Folic acid deficiency prenatal vitamins, yeast,
  liver, o.j., green leafies

78
F. Neural tube defects (NTF)

• 1. THE problem neural tube fails to close.
• 2. Most common spina bifida
• 3. Incidence of NTDs 1 or 2 per 1,000
• 4. Etiology genetic, folic acid deficiency
• 5. S/S neuro. Paralysis spastic or flaccid
  sensory loss (decubiti)

79
F. Neural tube defects (NTF)

• 1. THE problem neural tube fails to close.
• 2. Most common spina bifida
• 3. Incidence of NTDs 1 or 2 per 1,000
• 4. Etiology genetic, folic acid deficiency
• 5. S/S neuro. Paralysis spastic or flaccid
  sensory loss (decubiti)
• 75 in LS vertebrae (esp. L5-S1) Table of
  innervation (589) incontinence of B B
  (controlled at S2-4) in almost all cases.

80
F. Neural tube defects (NTF)

• 1. THE problem neural tube fails to close.
• 2. Most common spina bifida
• 3. Incidence of NTDs 1 or 2 per 1,000
• 4. Etiology genetic, folic acid deficiency
• 5. S/S neuro. Paralysis spastic or flaccid
  sensory loss (decubiti)
• 75 in LS vertebrae (esp. L5-S1) Table of
  innervation (589) incontinence of B B
  (controlled at S2-4) in almost all cases.
• 25 in T greater loss. Scoliosis, balance.

81
F. Neural tube defects (NTF)

• 1. THE problem neural tube fails to close.
• 2. Most common spina bifida
• 3. Incidence of NTDs 1 or 2 per 1,000
• 4. Etiology genetic, folic acid deficiency
• 5. S/S neuro. 75 in LS. 25 in T.
• 6. Medical management.
• Prenatal detection by AFP levels (amniocentesis),
  US detects if open NTD. Plan C-section so not
  injury.
• Need surgical closure within 48 hours (or nerves
  dry out) shunt for hydrocephalus B B
  management.

82
F. Neural tube defects (NTF)

• 1. THE problem neural tube fails to close.
• 2. Most common spina bifida
• 3. Incidence of NTDs 1 or 2 per 1,000
• 4. Etiology genetic, folic acid deficiency
• 5. S/S neuro. 75 in LS. 25 in T.
• 6. Medical management prenatal, C-section, Sx.
• 7. Px 85 survive to adulthood 2/3 normal
  intelligence. If can walk/use w/c by age 7, good
  Px

83
F. Neural tube defects (NTF)

• 1. THE problem neural tube fails to close.
• 2. Most common spina bifida
• 3. Incidence of NTDs 1 or 2 per 1,000
• 4. Etiology genetic, folic acid deficiency
• 5. S/S neuro. 75 in LS. 25 in T.
• 6. Medical management prenatal, C-section, Sx.
• 7. Px 85 survive to adulthood 2/3 normal
  intelligence. If can walk/use w/c by age 7, good
  Px
• 8. PT implications (592) joints/pain,
  ambulation, skin infection/breakdown.

84
CHAPTER 19 OVERVIEW

• A. Introduction to types of genetic or
  developmental disorders
• B. Terms word roots an-, bifid-, -cele, cyst,
  dys-, enceph-, mening-, myelo-, occult, -plasia
• C. Cerebral palsy (CP)
• D. Down syndrome
• E. Scoliosis
• F. Neural tube defects (NTD) (spina bifida)
• G. Developmental dysplasia of hip (DDH)
• H. Legg-Calve-Perthes disease

85
G. Congenital hip dysplasia (CHD)

• 1. Abnormal G D of hip
• Usually at birth or
• Usually unilateral (75) (FYI L 3X more than R)
  may be bilateral (25)

86
G. Congenital hip dysplasia (CHD)

• 1. Abnormal G D of hip
• Usually at birth or
• Usually unilateral (75) may be bilateral (25)
• Degrees of severity
• Mild (Type III) unstable or suluxable upon
  manipulation. 80 will resolve by age 2 months
• Moderate (Type II) incomplete dislocation
  (subluxed)
• Severe (Type I) complete (frank) dislocation

87
G. Congenital hip dysplasia (CHD)

• 1. Abnormal G D of hip
• Usually at birth or
• Usually unilateral (75) may be bilateral (25)
• Degrees of severity
• Mild (Type III) unstable or suluxable upon
  manipulation. 80 will resolve by age 2 months
• Moderate (Type II) incomplete dislocation
  (subluxed)
• Severe (Type I) complete (frank) dislocation
• Classifications by tests (FYI read and see
  figures, 596-597), such as Ortelanis maneuver
  (hip click)

88
G. Congenital hip dysplasia (CHD)

• 1. Abnormal G D of hip
• Usually at birth or
• Usually unilateral (75) may be bilateral (25)
• Degrees of severity
• Mild (Type III) unstable or suluxable
• Moderate (Type II) incomplete dislocation
  (subluxed)
• Severe (Type I) complete (frank) dislocation
• Classifications by tests (FYI read and see
  figures, 596-597), such as Ortelanis maneuver
  (hip click). Newborns hips should not have hip
  click.

89
G. Congenital hip dysplasia (CHD)

• 1. Abnormal G D of hip severity (Types I-III)
• 2-3. Incidence, risk factors, etiology
• 85 in females.
• FYI 1 in 1,000

90
G. Congenital hip dysplasia (CHD)

• 1. Abnormal G D of hip severity (Types I-III)
• 2-3. Incidence, risk factors, etiology
• 85 in females.
• FYI 1 in 1,000
• Family Hx
• Space issue in utero (twin, large baby movement
  limited)

91
G. Congenital hip dysplasia (CHD)

• 1. Abnormal G D of hip severity (Types I-III)
• 2-3. Incidence, risk factors, etiology
• 85 in females FYI 1 in 1,000
• Family Hx
• Space issue in utero (twin, large baby movement
  limited)
• Much CHD occurs perinatally re to positioning
  breech hips are F, ADD, with knees extended
  --- CHD). Ligamentous laxity.

92
G. Congenital hip dysplasia (CHD)

• 1. Abnormal G D of hip severity (Types I-III)
• 2-3. Incidence, risk factors, etiology
• Female Family Hx Space in utero
• Much CHD occurs perinatally re to positioning
  breech hips are F, ADD, with knees extended
  --- CHD). Ligamentous laxity.
• Also in cultures where baby swaddled so hips
  extended and adducted. US babies carried with
  hips F, ABD, Ext. rot prevents hip dysplasia.

93
G. Congenital hip dysplasia (CHD)

• 1. Abnormal G D of hip
• 2-3. Incidence, risk factors, etiology
• Female Family Hx Space in utero
  Breech Swaddling
• If other muscular deformities (CP spasticity,
  myelomeningocele, spinal instability/scoliosis).
  (Fig. 595 iliopsoas and adductor spasticity
  pulls so much on lesser trochanter that the
  femoral head is pushed laterally and dislocated).
  More on this later.

94
G. Congenital hip dysplasia (CHD)

• 1. Abnormal G D of hip
• 2-3. Incidence, risk factors, etiology
• Female Family Hx Space in utero
  Breech Swaddling
• If other muscular deformities (CP spasticity,
  myelomeningocele, spinal instability/scoliosis).
  (Fig. 595 iliopsoas and adductor spasticity
  pulls so much on lesser trochanter that the
  femoral head is pushed laterally and dislocated).
  More on this later.
• FYI also with some (5) club foot (p. 19-10)
  (stand on heels dorsiflexed with soles out
  everted) since hips adducted

95
G. Congenital hip dysplasia (CHD)

• 4. Pathogenesis
• Hip structures develop by week 10 of gestation
• Normal development requires that femoral head
  fit well into acetabulum

96
G. Congenital hip dysplasia (CHD)

• 4. Pathogenesis
• Hip structures develop by week 10 of gestation
• Normal development requires that femoral head
  fit well into acetabulum
• If not, femoral capital (head) epiphysis growth
  delayed head is flatter acetabular dysplasia.

97
G. Congenital hip dysplasia (CHD)

• 4. Pathogenesis
• Hip structures develop by week 10 of gestation
• Normal development requires that femoral head
  fit well into acetabulum
• If not, femoral capital (head) epiphysis growth
  delayed head is flatter acetabular dysplasia.
• Then soft tissues abnormal (ligamentum teres)
  adductors, iliopsoas --- contractures so femoral
  head dislocates further over first 3-4 years.

98
G. Congenital hip dysplasia (CHD)

• 4. Pathogenesis
• Hip structures develop by week 1o of gestation
• Normal development requires that femoral head
  fit well into acetabulum
• If not, femoral capital (head) epiphysis growth
  delayed head is flatter
• Then soft tissues abnormal (ligamentum teres)
  adductors, iliopsoas --- contractures so femoral
  head dislocates further over first 3-4 years.
  (Fig. 595 iliopsoas and adductor spasticity
  pulls so much on lesser trochanter that the
  femoral head is pushed laterally and dislocated).

99
G. Congenital hip dysplasia (CHD)

• 1. Abnormal G D of hip
• 2-3. Incidence, risk factors, etiology
• 4. Pathogenesis
• Flat femoral capital (head) epiphysis development
  with abnormal soft tissues (adductors, iliopsoas,
  ligamentum teres)--- contractures
• 5. Medical management (screen for hip click)
• Double diaper or (Pavlik) harness F, ABD hips
• Maybe hip cast. If not Tx DJD, hip pain

100
CHAPTER 19 OVERVIEW

• A. Introduction to types of genetic or
  developmental disorders
• B. Terms word roots an-, bifid-, -cele, cyst,
  dys-, enceph-, mening-, myelo-, occult, -plasia
• C. Cerebral palsy (CP)
• D. Down syndrome
• E. Scoliosis
• F. Neural tube defects (NTD) (spina bifida)
• G. Congenital hip dysplasia (CHD)
• H. Legg-Calve-Perthes disease (hip)

101
H. Legg-Calve-Perthes disease

• 1. Overview
• THE most common of the osteochondroses
  degenerative changes in ossification centers of
  epiphyses during periods of rapid growth. May
  lead to avascular (maybe septic) necrosis and
  then slow healing/repair

102
H. Legg-Calve-Perthes disease

• 1. Overview
• THE most common of the osteochondroses
  degenerative changes in ossification centers of
  epiphyses during periods of rapid growth. May
  lead to avascular (maybe septic) necrosis and
  then slow healing/repair
• LCP affects proximal femoral epiphysis (head is
  flattened)

103
H. Legg-Calve-Perthes disease

• 1. Overview
• THE most common of the osteochondroses
  degenerative changes in ossification centers of
  epiphyses during periods of rapid growth. May
  lead to avascular (maybe septic) necrosis and
  then slow healing/repair. See these in growing
  children (or adolecents)
• LCP affects proximal femoral epiphysis (head is
  flattened)
• Sound familiar??? As in CHD. But difference is
  timing. CHD may start EARLY (in utero)

104
H. Legg-Calve-Perthes disease

• 1. Overview
• Osteochondroses --- avascular necrosis and then
  slow healing/repair
• LCP affects proximal femoral epiphysis (head
  flattened)
• 2. Incidence, risk factors
• Ages 4-8 years (or 3-12) and then self-limiting.
• (FYI mostly in white boys and unilateral)

105
H. Legg-Calve-Perthes disease

• 1. Overview
• Osteochondroses --- avascular necrosis and then
  slow healing/repair
• LCP affects proximal femoral epiphysis (head
  flattened)
• 2. Incidence, risk factors
• Ages 4-8 years (or 3-12) and then self-limiting
• (FYI mostly in white boys and unilateral)
• 3. Etiology??? (FYI may be related to trauma,
  inflammation, clotting disorder) Ischemia ---
  revascularization --- hopefully femoral head
  reforms normally. (Self-limiting)

106
H. Legg-Calve-Perthes disease

• 1. Overview
• Osteochondroses --- avascular necrosis and then
  slow healing/repair flattened femoral head
• 2. Incidence, risk factors
• Ages 4-8 yrs (or 3-12) self-limiting (FYI
  white M).
• 3. Etiology??? Ischemia --- revascularization
  --- hopefully femoral head reforms normally
• 4. S/S restricted hip movement on affected side
  limp pain maybe atrophy of affected muscles.
  May lead to premature osteoarthritis in adulthood.

107
H. Legg-Calve-Perthes disease

• 1. Overview
• Osteochondroses --- avascular necrosis and then
  slow healing/repair flattened femoral head
• 2. Incidence, risk factors
• Ages 4-8 yrs (or 3-12) self-limiting (FYI
  white M).
• 3. Etiology??? Ischemia --- revascularization
  --- hopefully femoral head reforms normally
• 4. S/S restricted hip movement limp pain
  maybe atrophy of affected muscles. May --- OA.
• 5. Tx cast (hip ABD) to seat femoral head well.

108
CHAPTER 19 OVERVIEW, cont.

• H. Legg-Calve-Perthes (osteochondrosis the most
  common of hip flat femoral head)
• I. Osgood-Schlatter (osteochondrosis of knee)
• J. Osteogenesis perfecta
• K.Skeletal developmental problems (genu varum,
  genu valgum, tibial or femoral torsion, clubfoot
• L. Muscular dystrophy (MD)
• M. Torticollis N. Erbs palsy
• O. Arthrogryposis mutiplex congenita (AMC)
• P. Spinal muscular atrophy (SMA)

109
I. Osgood-Schlatter disease (osteochondrosis)

• Osteochondroses degenerative changes in
  ossification centers of epiphyses during periods
  of rapid growth. May lead to avascular (maybe
  septic) necrosis and then slow healing/repair.
  Seen in growing children/adolescents.
• 1. Overview

110
I. Osgood-Schlatter disease (osteochondrosis)

• Osteochondroses degenerative changes in
  ossification centers of epiphyses during periods
  of rapid growth. May lead to avascular (maybe
  septic) necrosis and then slow healing/repair.
  See these in growing children/adolescents.
• 1. Overview
• a form of tendonitis at the knee
• patellar tendon tugs at tibial tuberosity and
  pulls bits of maturing bone from the t.t.

111
I. Osgood-Schlatter disease (osteochondrosis)

• 1. Overview
• a form of tendonitis
• patellar tendon tugs at tibial tuberosity and
  pulls bits of maturing bone from the t.t.
• 2. Incidence more in active boy adolescents
• 3. Etiology intense quads tendon pull on t.t.
  (or repeated knee flexion) before complete fusion
  of epiphysis to diaphysis of tibia

112
I. Osgood-Schlatter disease (osteochondrosis)

• 1. Overview
• a form of tendonitis at tibial tuberosity
• 2. Incidence active boys
• 3. Etiology XS knee action before complete
  fusion of epiphysis to diaphysis of tibia
• 4. S/S
• aching pain with knee movements
• enlarged tibial tuberosity
• 5. Tx
• 6. Px

113
I. Osgood-Schlatter disease (osteochondrosis)

• 1. Overview
• a form of tendonitis at tibial tuberosity
• 2. Incidence active boys
• 3. Etiology XS knee action before complete
  fusion of epiphysis to diaphysis of tibia
• 4. S/S
• aching pain with knee movements
• enlarged tibial tuberosity
• 5. Tx rest (so can revascularize t.t.), NSAIDs

114
I. Osgood-Schlatter disease (osteochondrosis)

• 1. Overview
• a form of tendonitis at tibial tuberosity
• 2. Incidence active boys
• 3. Etiology XS knee action before complete
  fusion of epiphysis to diaphysis of tibia
• 4. S/S
• aching pain with knee movements
• enlarged tibial tuberosity
• 5. Tx rest (so can revascularize t.t.), NSAIDs
• 6. Px should resolve after tibial growth complete

115
CHAPTER 19 OVERVIEW, cont.

• H. Legg-Calve-Perthes (childs hip flat head)
• I. Osgood-Schlatter disease (adolescent knee)
• J. Osteogenesis imperfecta
• K.Skeletal developmental problems (genu varum,
  genu valgum, tibial or femoral torsion, clubfoot
• L. Muscular dystrophy (MD)
• M. Torticollis
• N. Erbs palsy
• O. Arthrogryposis mutiplex congenita (AMC)
• P. Spinal muscular atrophy (SMA)

116
J. Osteogenesis imperfecta(brittle bones)

• 1. Hereditary disease autosomal dominant (need
  only 1 bad gene so 50 chance if 1 parent has
  it)
• 2. Pathogenesis
• 3. S/S
• 4. Tx

117
J. Osteogenesis imperfecta(brittle bones)

• 1. Hereditary disease autosomal dominant (need
  only 1 bad gene so 50 chance if 1 parent has
  it)
• 2. Pathogenesis defect in collagen synthesis so
  brittle bones and other tissues affected
• 3. S/S (depend on severity)
• Bones may be so brittle that in utero Fx x-rays
  of child may suggest child abuse short
  extremities muscle atrophy
• Abnormal tendons, ligaments, heart valves,
  sclerae, deformed teeth (all contain collagen)

118
J. Osteogenesis imperfecta(brittle bones)

• 1. Hereditary disease autosomal dominant (need
  only 1 bad gene so 50 chance if 1 parent has
  it)
• 2. Pathogenesis defect in collagen synthesis so
  brittle bones and other tissues affected
• 3. S/S (depend on severity)
• Brittle, short bones muscle atrophy
• Other connective tissues ABN
• 4. Tx no effective Tx if severe. Rods within
  bones maye help prevent Fx.

119
CHAPTER 19 OVERVIEW, cont.

• I. Osgood-Schlatter disease (adolescent knee)
• J. Osteogenesis perfecta (brittle bones)
• K.Skeletal developmental problems (genu varum,
  genu valgum, tibial or femoral torsion, clubfoot
• L. Muscular dystrophy (MD)
• M. Torticollis
• N. Erbs palsy
• O. Arthrogryposis mutiplex congenita (AMC)
• P. Spinal muscular atrophy (SMA)

120
K.Skeletal developmental problems

• 1. Genu varum
• Bowlegs (on horse)
• Bowing of knees 1 when inner ankles
  touching
• Normal to 2 yrs
• Varus feet bent inward
• Maybe bracing

• 2. Genu valgum
• Knock-knees
• When knees touch, inner ankles cannot touch
• Valgus feet bent outwards
• Seen most 2-6 yrs should resolve by 10
• Medial collateral ligament laxity M

121
K. Skeletal development problems, cont.

• 3a. Tibial torsion
• Toeing in
• Genetic or
• Splint (bar with shoes) puts feet in mild Ext.
  rot.

• 3b. Femoral torsion
• Toeing out (as in child sitting in W
  position)

122
K. Skeletal development problems, cont

• 4. Clubfoot (talipes)
• Congenital deformity of one or both feet
• Usually idiopathic may be due to failure of
• leg to rotate or
• soft tissue maturation

123
K. Skeletal development problems, cont

• 4. Clubfoot (talipes)
• Congenital deformity of one or both feet
• Usually idiopathic may be due to failure of
• leg to rotate or
• soft tissue maturation
• Categories
• 95 plantar flexion and inversion. Like horses
  hoof (FYI equinovarus)

124
K. Skeletal development problems, cont

• 4. Clubfoot (talipes)
• Congenital deformity of one or both feet
• Usually idiopathic may be due to failure of leg
  to rotate or soft tissue maturation
• Categories
• 95 plantar flexion and inversion. Like horses
  hoof (FYI equinovarus)
• 5 dorsiflexion and eversion stand on heels and
  soles outward) (FYI calcaneovalgus) --- CHD

125
G. Congenital hip dysplasia (CHD)

• 1. Abnormal G D of hip
• 2-3. Incidence, risk factors, etiology
• Female Family Hx Space in utero
  Breech Swaddling
• If other muscular deformities (CP spasticity,
  myelomeningocele, spinal instability/scoliosis).
  (Fig. 595 iliopsoas and adductor spasticity
  pulls so much on lesser trochanter that the
  femoral head is pushed laterally and dislocated).
  More on this later.
• Also with some (5) club foot (p. 19-10) (stand
  on heels dorsiflexed with soles out everted)
  since hips adducted

126
K. Skeletal development problems, cont

• 4. Clubfoot (talipes)
• Congenital deformity of one or both feet
• Usually idiopathic may be due to failure of leg
  to rotate or soft tissue maturation
• Categories S/S depend on severity
• 95 plantar flexion and inversion. Like horses
  hoof (FYI equinovarus)
• 5 dorsiflexion and eversion stand on heels and
  soles outward) (FYI calcaneovalgus) --- CHD

127
CHAPTER 19 OVERVIEW, cont.

• I. Osgood-Schlatter disease (adolescent knee)
• J. Osteogenesis perfecta (brittle bones)
• K.Skeletal developmental problems (genu varum,
  genu valgum, tibial or femoral torsion, clubfoot
• L. Muscular dystrophy (MD)
• M. Torticollis
• N. Erbs palsy
• O. Arthrogryposis mutiplex congenita (AMC)
• P. Spinal muscular atrophy (SMA)

128
L. Muscular dystrophy

• 1. Overview, incidence
• 2. Etiology, pathogenesis
• 3. S/S
• 4. Medical management Dx, Tx, Px
• 5. PT implications

129
L. Muscular dystrophy

• 1. Overview, incidence
• most common progressive neuromuscular disorders.
  All hereditary.
• 2. Etiology, pathogenesis

130
L. Muscular dystrophy

• 1. Overview, incidence
• most common progressive neuromuscular disorders.
  All hereditary.
• Symmetrical muscle wasting/disability. Fatty CT
  replaces muscle, so may not appear emaciated. No
  sensory loss.
• 2. Etiology, pathogenesis

131
L. Muscular dystrophy

• 1. Overview, incidence
• most common progressive neuromuscular disorders.
  All hereditary.
• Symmetrical muscle wasting/disability. Fatty CT
  replaces muscle, so may not appear emaciated. No
  sensory loss.
• Four types. Duchennes MD (DMD) 50 of cases
  X-linked. So only (males? females?) get it.
• 2. Etiology, pathogenesis

132
L. Muscular dystrophy

• 1. Overview, incidence
• most common progressive neuromuscular disorders.
  All hereditary.
• Symmetrical muscle wasting/disability. Fatty CT
  replaces muscle, so may not appear emaciated. No
  sensory loss.
• Four types. Duchennes MD (DMD) 50 of cases
  X-linked. So only (males? females?) get it.
• 2. Etiology, pathogenesis

133
L. Muscular dystrophy

• 1. Overview, incidence
• most common progressive NM disorders hereditary.
• Symmetrical muscle wasting/disability. Fatty CT
  replaces muscle, so may not appear emaciated.
• Four types. Duchennes MD (DMD) 50 of cases
  X-linked. So only (males? females?) get it.
• 2. Etiology, pathogenesis
• An X gene (p21) normally codes from dystrophin
  that links sarcolemma to contractile protein,
  actin.
• Males with DMD lack this gene, so lack
  dystrophin. Sarcolemma is damaged during
  contraction muscle protein synthesis decreased
  fatty replacement.

134
L. Muscular dystrophy

• 1. Overview, incidence
• 2. Etiology, pathogenesis
• Males with DMD lack Xp21 gene, so lack
  dystrophin. Sarcolemma is damaged during
  contraction muscle protein synthesis decreased
  fatty replacement.
• 3. S/S hypotonia
• Gowers sign (weak gluteals) walk hands up
  legs/thighs
• Waddling gait walk on toes lose ability to
  ambulate
• Shoulder, thoracic/respiratory muscles affected
• Myocardium --- CHF

135
L. Muscular dystrophy

• 1. Overview, incidence
• 2. Etiology, pathogenesis Males with DMD lack
  Xp21 gene, so lack dystrophin.
• 3. S/S hypotonia Gowers sign (weak gluteals)
  walk hands up legs/thighs lose ability to
  ambulate shoulder, thoracic/respiratory muscles
  affected myocardium
• 4. Medical management
• Dx EMG, muscle biopsy serum CK high family Hx
  CVS (dystrophin gene deleted)
• Tx no cure maintain affected muscles gene
  therapy death by respiratory/cardiac
  complications

136
CHAPTER 19 OVERVIEW, cont.

• I. Osgood-Schlatter disease (adolescent knee)
• J. Osteogenesis perfecta (brittle bones)
• K.Skeletal developmental problems
• genu varum (bowlegs) genu valgum (knock-knees)
• tibial torsion (toeing-in) femoral torsion
  (toeing out)
• clubfoot (95 plantar flexion inversion)
• L. Muscular dystrophy (MD) DMD males
• M. Torticollis
• N. Erbs palsy
• O. Arthrogryposis mutiplex congenita (AMC)
• P. Spinal muscular atrophy (SMA)

137
CHAPTER 19 OVERVIEW, cont.

• I. Osgood-Schlatter disease (adolescent knee)
• J. Osteogenesis perfecta (brittle bones)
• K.Skeletal developmental problems
• L. Muscular dystrophy (MD) DMD males
• M. Torticollis
• Wry neck via XS SCM contraction (palpable)
• Congenital or by spinal accessory n. damage
• So limited neck movements
• Tx PROM, AROM. Recovery usually

138
CHAPTER 19 OVERVIEW, cont.

• I. Osgood-Schlatter disease (adolescent knee)
• J. Osteogenesis perfecta (brittle bones)
• K.Skeletal developmental problems
• genu varum, genu valgum (knock-knees)
• tibial torsion (toeing-in), femoral torsion
  (toeing out)
• clubfoot (95 plantar flexion inversion)
• L. Muscular dystrophy (MD) DMD males
• M. Torticollis wry neck (CN XI)
• N. Erbs palsy
• O. Arthrogryposis mutiplex congenita (AMC)
• P. Spinal muscular atrophy (SMA)

139

• N. Erbs palsy brachial plexus injured
• Cause L/D, by abuse (nursemaids palsy swing by
  1 arm)

140

• N. Erbs palsy brachial plexus injured
• Cause L/D, by abuse (nursemaids palsy swing by
  1 arm)
• 95 cases (Erb-Duchenne palsy) C5-C6 waiters
  tip position straight arm, palm back, flex
  wrist
• ADD/EXTEND/INT ROT humerus
• EXT/PRONATE forearm FLEX wrist

141
Effects of C5-C6 damage. Cannot
142
Effects of C5-C6 damage. Cannot
143
Effects of C5-C6 damage. Cannot
144
Effects of C5-C6 damage. Cannot
145
CHAPTER 19 OVERVIEW, cont.

• I. Osgood-Schlatter disease (adolescent knee)
• J. Osteogenesis perfecta (brittle bones)
• K.Skeletal developmental problems
• genu varum (bowlegs) genu valgum (knock-knees)
• tibial torsion (toeing-in) femoral torsion
  (toeing out)
• clubfoot (95 plantar flexion inversion)
• L. Muscular dystrophy (MD)
• M. Torticollis wry neck
• N. Erbs palsy nursemaids palsy (waiters tip)
• O. Arthrogryposis mutiplex congenita (AMC)
• P. Spinal muscular atrophy (SMA)

146

• O. Arthrogryposis multiplex congenita (AMC)
• Joints stay fixed (flexed or extended position
• Causes (FYI) autosomal dominant?, viral
  infection, small amount of amniotic fluid (so
  child in cramped position), poor uteroplacental
  circulation, LMNs not stimulate muscles
• S/S akinesia, joint deformities (risk of CHD),
  motor limitations. May have normal intelligence

147
CHAPTER 19 OVERVIEW, cont.

• I. Osgood-Schlatter disease (adolescent knee)
• J. Osteogenesis perfecta (brittle bones)
• K.Skeletal developmental problems
• genu varum (bowlegs) genu valgum (knock-knees)
• tibial torsion (toeing-in) femoral torsion
  (toeing out)
• clubfoot (95 plantar flexion inversion)
• L. Muscular dystrophy (MD)
• M. Torticollis wry neck
• N. Erbs palsy nursemaids palsy (waiters tip)
• O. Arthrogryposis mutiplex congenita (AMC)
• P. Spinal muscular atrophy (SMA) floppy infant

148

• P. Spinal muscular atrophy (SMA)
• Floppy infant syndrome (progressive, wasting of
  skeletal muscles due to motor neuron degneration)
• Cause autosomal recessive if both parents
  carrier, 25 of children likely to have this.
  (FYI 2 most common autosomal recessive disorder
  after CF)
• S/S weakness, chronic respiratory problems,
  static postures --- decubiti
• Degrees of severity if severe, death by 3 yrs

149
BIO 301PT CHAPTER 19

• Genetic and Developmental Disorders
• The End!!!

150
Slides that follow are FYI only
151

• A gene for an autosomal disorder may be autosomal
  dominant
• Only 1 parent needs to have the dominant BAD
  gene for a child to get it.
• If child gets that gene from parent, child has
  the disorder.

152

• A gene for an autosomal disorder may be autosomal
  dominant
• Only 1 parent needs to have the dominant BAD
  gene for a child to get it.
• If child gets that gene from parent, child has
  the disorder.
• Each child has a 50-50 chance to get the BAD gene
  from the affected parent
• Example HD, Marfans, hypercholesterol-emia
  most osteogenesis imperfecta, AMC (arthrogryposis
  multiplex congenita)

153

• A gene for an autosomal disorder may be
  autosomal recessive
• Both parents must have the gene for child to get
  it
• If child gets the recessive ( BAD gene) from
  both parents, child has the disorder since child
  did not get a GOOD (dominant) gene from either
  parent.

154

• A gene for an autosomal disorder may be
  autosomal recessive
• If child gets the recessive ( BAD gene) from
  both parents, child has the disorder since child
  did not get a GOOD (dominant) gene from either
  parent.
• Each child has a 25 chance of having the
  disorder (and 50 chance of being carrier)
• Examples cystic fibrosis (CF), sickle cell
  anemia (SCA), phenylketonuria (PKU), SMA (spinal
  muscular atrophy)

155

• A gene for an X-linked disorder may be recessive
  (most are) or dominant
• Females rarely get the disorder if one X
  chromosome has the bad (recessive) gene, they
  have another X chromosome that can carry the good
  (dominant) gene to override the bad one. They are
  carriers if have one bad, one good.
• X-linked condiions affect males (almost
  exclusively). Males cannot be carriers. They have
  only one X with the bad gene or not.
• Examples hemophila, some color-blindness,
  Duchennes muscular dystrophy (DMD)