myopathy

meaning in plain English

A problem that makes the muscles weak or painful and isn’t caused by nerve trouble.

Think my (my) + pathology: my own muscle trouble – myopathy means muscles feel weak or hurt, not nerves.

for example

After the marathon, the doctor said her lingering muscle weakness was due to myopathy, not a nerve injury.

If your muscles stay sore and stiff for weeks but doctors find no nerve damage, they may call it myopathy. That word means the trouble is coming from the muscles themselves, not the nerves.