Proximal Myopathy
Examination
 On detecting proximal weakness, proceed to test sensation to rule out neuropathic
weakness; skip the cerebellar; waddling gait
 If unilateral proximal weakness, think of diabetic amyotrophy (a/w pain and
sensory impairment)
 Check the ULs
 Acromegaly, Cushing’s
 Dupuytren contracture
 Dermatomyositis/Polymyositis
 Proximal weakness
 Check the Face
 Eyes for MG
 Cushing’s, Acromegaly, Thyroid
 Parotids
Presentation
Sir this patient has proximal weakness of the upper and lower limbs that is due to
proximal myopathy.
There is presence of weakness with a power of 4 on the upper and lower limb girdle
muscles. I was able to overcome his abduction of the arms and he has difficulty
standing from a sitting/squatting position. There is presence of a waddling gait.
There is no evidence of any sensory involvement. There is also no fatigability.
There were no features of
 Dermatomyositis/polymyositis
 Acromegaly/Cushing’s/Thyroid
 Chronic ethanol ingestion – Dupuytren and parotidomegaly
 Sarcoid – lupus pernio
 Cancer – cachexia, clubbed
I would like to take a drug history
 Cholesterol lowering drugs
 Corticosteroids
 Cyclosporine A
 Chloroquine
The possible etiologies include:
 Congenital
 Duchenne’s
 Sex linked, young male child, onset 3-4yrs
 Pseudohypertrophy of the calves
 Proximal weakness – Gower’s sign, usually cannot ambulate by 15yrs
 No facial involvement
 Low IQ
 Dilated cardiomyopathy


Becker’s
 Similar but less severe to Duchenne
 Can ambulate beyond 15 years
 Usually onset 5-15 but maybe 3rd/4th decades
 Majority survive to 4th/5th decades
 Dx – Western blot of muscle biopsy – abnormal/reduced dystrophin
 Limb Girdle
 AR, 10-30 yrs old, progressive with severe disability in 20yrs
 Shoulder and pelvic girdle affected
 Deltoids are spared initially – pseudohypertrophy
 Biceps and brachioradialis are involved late
 Hip flexors and glutei are weak
 Early wasting of medial quads and tibialis anterior with lateral quads
and calves being pseudo hypertrophied
 Face is never involved and normal IQ and lifespan
 Normal muscle enzymes
 Fascioscapular and oculopharyngeal – see ULs
Acquired
 P – Polymyositis/Dermatomyositis, polymyalgia rheumatica
 A – Alcohol
 C – Cancer
 H – HIV
 E – Endocrine (Acromegaly, Cushing’s, Thyroid), ESRF
 M – Mitochondrial myopathy (Myopathy, External ophthalmoplegia, red
ragged fibres and lactic acidemia), McArdle’s syndrome (weakness after
exercise)
 P – Periodic Paralysis
 O – osteomalacia
 D – Drugs
 S - Sarcoid