Myotonic disorders

myotonia= delayed relaxation after sustained mm contraction
1. IDed clinically and on EMG
dystrophia myotonica
1. dominantly inherited
2. caused by nucleotide triplet expansion
  1. so there can be anticipation through the generations
    1. esp when maternally transmitted
3. presentation
  1. newborns
    1. hypotonia
    2. resp & feeding difficulties
      1. due to mm weakness
    3. good to examine mum for myotonia
      1. manifestation
        slow release of handshake
        difficulty releasing tightly clasped fist
  2. older kids
    1. myopathic facies
    2. LD
    3. myotonia
4. diagnosis
  1. imp to be sensitive while giving diag in the neonate
5. adults
  1. cataracts
  2. males
    1. baldness
    2. testicular atrophy
6. death usually due to cardiomyopathy

Resource summary

	Created by v.djabatey over 10 years ago