2. • Causes
• Inheritance
• Dominant genes
• Recessive gene
Depends on the age when symptoms appear, and the
types of symptoms that develop.
• Risk
• Because these are inherited disorders, risk include a
family history of muscular dystrophy
How Many People Are Affected
It is estimated that between 50,000 -250,000 are
affected annually. 1 per 3500 live male births
3.
4. • Muscular dystrophy is a heterogeneous
group of inherited disorders recognized
by progressive degenerative muscle
weakness and loss of muscle tissue
(started in childhood).
• Affect muscles strength and action.
• Generalized or localized.
• Skeletal muscle and other organs may
involve
• Limitation: Difficulties with walking or Maintaining posture,
Muscle spasms. Neurological, Behavioral, Cardiac, or other
Functional limitations.
14. • Most common
• male, Turner
syndrome
• 1:3500 live
male birth
• 1/3 new
mutation
• 65% family
history
15. Clinical manifestation
• Onset : age 3-6
years
• Progressive
weakness
• Pseudohypertrophy
of calf muscles
• Spinal deformity
• Cardiopulmonary
involvement
• Mild - moderate MR
16. Natural history
• Progress slowly and
continuously
• muscle weakness
▫ lower --> upper
extremities
• unable to ambulate: 10
year (7-12)
• death from pulmonary/
cardiac failure: 2-3rd de
cade
27. • Milder version of
DMD
• Etiology
▫ single gene defect
▫ short arm X
chromosome
▫ altered size &
decreased amount
of dystrophin
28.
29. • Less common
▫ 1: 30000 live male birth
• Less severe
• Family history: atypical MD
• Similar & less severe than DMD
• Onset: age > 7 years
• Pseudohypertrophy of calf
• Equinous and varus foot
• High rate of scoliosis
• Less frequent cardiac involvement
Clinical features
30. Diagnosis
• The same as DMD
• Increase CPK (<200x)
• Decrease dystrophin and/or altered size
Natural history
▫ Slower progression
▫ ambulate until adolescence
▫ longer life expectancy
Treatment
▫ the same as in DMD
▫ forefoot equinous: plantar release, midfoot dorsal-
wedge osteotomy
40. •Classification
▫ Pelvic girdle type
common
▫ Scapulohumeral
type
rare
• Diagnosis
▫ Same clinical as
DMD/BMD carriers
▫ Moderately elevated
CPK
▫ Normal dystrophin
41. • Natural history
▫ Slow progression
▫ After onset > 20 y:
contracture &
disability
▫ Rarely significant
scoliosis
• Treatment
▫ Similar to DMD
▫ Scoliosis: mild, no
Rx.
42. Fascioscapulohumeral Muscular
Dystrophy
• Etiology
▫ Autosomal dominant
▫ Gene defect (FRG1)
▫ Chromosome 4q35
• Epidemiology
▫ Female > male
• Clinical
manifestation
▫ Age of onset: late
childhood/ early adult
▫ No cardiac, CNS
involvement
▫ Winging scapula
▫ Markedly decreased
shoulder flexion &
abduction
▫ Horizontal clavicles
▫ Rare scoliosis
43.
44. • Muscle weakness
▫ face, shoulder, upper arm
• Sparing
▫ Deltoid
▫ Distal pectoralis major
▫ Erector spinae
45. • “Popeye”
appearance
▫ Lack of facial mobility
▫ Incomplete eye
closure
▫ Pouting lips
▫ Transverse smile
▫ Absence of eye and
forehead wrinkles
POPEYE ARMS
46. • Diagnosis
▫ PE, muscle biopsy
▫ Normal serum
CPK
• Natural history
▫ Slow progression
▫ Face, shoulder m.
pelvic girdle,
tibialis ant
▫ Good life
expectancy
• Treatment
▫ Posterior
scpulocostal
fusion/ stabilization
(scapuloplexy)
47. Distal Muscular Dystrophy
• Autosomal dominant trait
• Rare
• Dysferlin (mb prot) defect
• Age of onset: after 45 yrs
• Initial involvement:
intrinsic hands, claves,
tibialis posterior
• Spread proximally
• Normal sensation
54. `Classical form' of the disease is seen in
adolescent or early adult life with variable
presenting features.
• Muscular weakness,
•myotonia,
•mental retardation,
•cataract,
•neonatal problems
•18% remain asymptomatic.
55. Summary
Clinical DMD LGMD FSMD DD CMD
Incidence common less Not common Rare Rare
Age of
onset
3-6 y 2nd decade 2nd decade 20-77 y At/ after birth
Sex Male Either sex M = F Either sex Both
Inheritance Sex-linked
recessive
AR, rare AD AD AD Unknown
Muscle
involve.
Proximal to
distal
Proximal to
distal
Face &
shoulder to
pelvic
Distal Generalized
Muscle
spread until
late
Leg, hand,
arm, face,
larynx,eye
Upper ex,
calf
Back ext,
hip abd,
quad
Proximal -
56. Clinical DMD LGMD FSMD DD CMD
Pseudo
hypertrophy
80%
calf
< 33% Rare no No
Contracture Common Late Mild, late Mild, late Severe
Scoliosis
Kyphoscoliosis
Common, late Late - - ?
Heart Hypertrophyt
achycardia
Very rare Very rare Very rare Not
observed
Intellectual decrease Normal Normal Normal ?
Course Stead, rapid Slow Insidious benign Steady
