Myopathies Flashcards
Studies for muscle
Electrophysiology
EMG NCV
NCV studies use
Probes
EMG use
needles
Most common entrapment syndrome
Carpal Tunnel syndrome
URTI B LE weakness Rubbery legs Ascending paralysis Ptosis Difficulty in ambulation DOB
Guillain Barraine Syndrome
Abnormal Spontaneous Activity
Fibrillation Potential
Myopathy
Abnormal Spontaneous Activity
Complex Repetitive Discharge
Myopathy
Myopathy presents with
1 Complex repetitive discharge
2 Fibrillations
Pathognomonic of myotonic dystrophy
Dive bomber sound
Trinucleotide repeat in myotonic dystrophy
CTG
Muscle fiber necrosis undergoing regeneration
Subsequent loss of muscle fibers
Muscular dystrophy
Most common primary myopathy
Muscular dystrophy
< 5 years old
Progressive weakness of girdle muscle
Pseudohypertrophy of Calf
Respiratory failure in 20s-30s
Duchenne Muscular Dystrophy
Gene deletion for DMD
60-70% of cases
Dystrophin
On PE, patients with DMD may elicit this sign
Gower’s sign
Use of UE to push up from the floor to standing
Pausing at thighs
Gower sign
Early stage of DMD
Pseudohypertrophy of calves
Gradual loss of muscle
10-12 years of DMD
Confined to wheelchair
2nd decade of life DMD
Death due to respiratory insufficiency
Mild form of DMD
Becker’s muscular dystrophy
Sex linked recessive Xp21
Partial deletion of the gene coding for dystrophin
Dystrophin is partially present
Muscle membrabe is semi functional
Becker’s Muscular Dystrophy
Genetically heterogenous group
90% AR
Less frequent than dystrophinopathies
Begins during adolescence or adulthood
Milder, slower progression
Trunk and proximal limb involvement
Variation in fiber size
Small angular fibers; occasionally hypertrophic
Limb Girdle Muscular Dystrophy
Proximal muscle weakness
Gower’s sign
Scapular winging
Limb Girdle Muscular Dystrophy
Multisystem disease of muscle, heart, eye, endocrine system and CNS
Weakness Myotonia (sustained muscle contraction) Cataract Cardiac arrhythmia Frontal balding
Myotonia Dystrophica
Steinert’s disease
CTG trinucleotide repeats in gene: DMPK
Autosominal dominance inheritance
Myotonia dystrophica
Myotonic dystrophy cataract
Christmas Tree Cataract
Mouth of patients with muscular dystrophy
Carp mouth
Myotonia
Muscle stiffness
Muscle hypertrophy “herculean appearance”
Gene mutation encoding chloride channel
Autosomal dominant inheritance
Myotonia Congenita
Rare neurologic disorder with features of autoimmune disease
Fluctuating muscle rigidity in the trunk and limbs and a heightened sensitivity to stimuli such as noise, touch, emotional distress which can set off muscle spasms
Stiff-person Syndrome
