Cause: X-linked recessive (XP21 band);Defective dystrophin

Clinical Features:

1. Delayed motor development

2. Gower Sign

3. Psudohypertrophy of calves

4. Kyphoscoliosis with contractures

5. Benign EKG abnormalities

6. Below average IQ

Labs:

CK= elevated X 10-20

EMG= small motor unit potentials

Muscle Biop= absent staining for dystropin

Treatment: Brace and attempt to aid mobility; Possibly predinisone slows progression.

Cause: X-linked recessive. More benign presentation than DMD. Similar gene defect.

Clinical Features:

1. Similar pattern to DMD

2. Weakness begins in proximal lower extremities; followed by neck flexors.

3. Most survive past 20 and ambulate till 16.

Labs:

CK= > 10X norm

ECG= Not as specific as DMD

EMG= myopathic pattern

Muscle Biopsy= dystropin detectable but altered structure

Treatment: Bracing; ambulatory and palative care

Cause: Autosomal dominant disorder of Chromosome 19. Demonstrates anticipation of trinucleotide repeats. (Most common adult dystrophy)

Clinical:

1. Onset in 2-3 decade

2. Facial abnormalities (temporalis wasting; facial and palate muscle wasting; nasal voice;some limb involvement)

3. Unable to quickly relax grip

4. Cardiac~possibly lead to heart block

5. < IQ

6. Respitory weakness (as with most dys)

7. Cataracts

8. Frontal Balding

Labs:

CK= norm

EMG= repetitive dicharges or single motor units-discharges; sounds like air bomb

Opthalmoscope: Cataracts

ECG= possible conduction defects

Treatment: Symptomatic; mechanical bracing

Cause: Autosomal dominant disorder. Chromosome 4

Clinical Features:

1. Onset 1st decade till middle age

2. Facial weakness; glum expression; can't use a straw

3. Significant scapular winging

4. 20% need wheel chair

5. Occasional hearing loss and vasuclar retinal disease

Labs:

Ck= Norm or mild elevation

EMG=myopathic

Treatment: Ankle bracking;Surgical fixation of scapula

Cause: Immune dysfunction~leads to complement mediated vasculopathy

Clinical Features:

1. Sun exposed scaly lesions on face, elbows, knuckles, knees.

2. Muscle weakness; proximal>distal

3. Myalgias

4. Joint Contractures

5.increased risk of cancer; concurrent CA

Labs:

CK= very elevated

EMG= Small motor unit potentials +Fibrillation potentials

Muscle Biopsy: PERIfascicular atrophy (B-cells)

Treatment: Steroids; Immunosupressants; IVIg

Cause: T cell attack of muscle fiber

Clinical Features:

1. Subacute weakness; proximal > dist

2. Dysphagia

3. Myalgias in 1/3

Labs:

CK= Elevated

EMG=Small motor unit potentials +Fibrillation potentials Muscle Biopsy: T cells with active fibrosis

Treatment: High dose steroids; Immunosurpressants (Azathioprine); IVIg

1) Steroid induced diabetes

2) Osteoporosis

3) Adrenal suppression (wean to avoid Addisons disease) 4) Cataracts

5) Weight gain and Cushings (Hypercortisolism)

6)Fragile skin

7)Mood fluctuations

8)Peptic ulcers

9)Suppressed immunity

Cause: T cell attack of muscle fibers with hereditary component

Clinical Features:

1. Age >50

2. Male > female

3. Slow progressive weakness; Quads and finger flexors.

4. NO Myalgias

5. 1/3 dysphagia

Labs: CK= mild elevated EMG= Muscle Biopsy= inclusion bodies~Rimmed vacuoles

NO treatments