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In this lecture, we're going to talk about Inherited Muscle Disorders in our review and
overview about how we think about and categorize these conditions. As you recall when
we're dealing with any neurologic disease, our first job is to figure out is the central nervous
system or peripheral nervous system. And we use the history and exam that guide us
towards peripheral nervous system localization. When we're thinking about the peripheral
nervous system, we're trying to localize to the muscle, the neuromuscular junction or the
nerve to guide us to what testing to do and how to evaluate the patient. For muscle disorders,
we can subclassify them as those that are hereditary and those that are acquired. At the
neuromuscular junction, we characterize those as pre or postsynaptic and that guides our
evaluation. And for the nerve, there's a number of ways that we can categorize those
conditions. Here we're going to focus on the muscle and we've talked a little bit about acquired
muscle disorders, now we're going to focus on hereditary myopathies. How do we evaluate
muscle disease? Well typically, we think of history, physical examination, routine blood work,
our EMG is important for demonstrating myopathic changes (a muscle problem). Imaging,
muscle biopsy, and a number of tests are utilized. We try and make a diagnosis. We think
about supportive care if necessary, physical/occupational/speech therapy for many patients,
and then we focus on the treatment. And for these inherited muscle disorders, what's going to
be key is early genetic testing. We're going to use our history and our physical examination
to figure out that this is a muscle disorder and it may be inherited and then genetic testing is
going to be key for making that diagnosis, understanding the prognosis, and guiding treatment
for these patients.