I stumbled across your post and I found myself relating to you very well.
Here is my story...
On Feb 2012, I was diagnosis with Ocular MG after suffering symptoms such as Diplopia, ptosis and etc. About 5 months prior I suffered a bad viral infection in Iraq. One doctor who is the is the director of Nuerology at University of South Florida and with a specialization in Neuromuscular disorder believes there is a close correlation between the two for the onset of MG. Anyways, the diagnosis was based on my symptoms and slightly evaluated Acetylcholine Receptor Antibodies. It was not high, but enough to diagnose me with myasthenia gravis. I also had a slightly enlarged thymus but no thymoma. I was then prescribed Mestinon (60mg) 4 times daily. I notice improvements in my diplopia and and ptosis immediately after taking the medication, which kinda made me be believe even more that I really do have Myasthenia Gravis. After taking the medication for several days, I felt that normal again with no symptoms at all, until I went to the gym. While I was working chest/triceps, I notice extreme muscle weakness in my tricep muscles. It almost felt as it was paralyzed. I began to monitor it closely and I notice that it was weak all the time, it didn't matter if I took high levels of Mestinon or zero Mestinion for weeks (I went weeks with out mestinon), the muscle didn't seem to response or get better. I began to get concern, I started to look at my medical history to find it there was anything in the pass the was going to haunt me. I was involved in a motorcycle accident in 2006, where I broke my right clavicle and suffered mild traumatic brain injury, but I seem to recover pretty well after the accident with no developing symptoms. I went to my neurologist and explain him what was going on. He want to look deeper so I had a Cervical MRI and EMG test done. The MRI did find some minor bulging in one of my disk but nothing major. The EMG test show that I had abnormal readings. With this information, my neurologist believes that I could be suffering cervical radiculopathy superimposed by my myasthenia gravis.
I'm not sure whats the next step, but I'm going to schedule a appointment with an orthopedic surgeon to get a second opinion, including follow up with my neurologist. All he has told me was to continue exercising and thats it. At the time he didn't seem to know what was next, hopefully my next visit he would have formulated some sort of plan. I really want to get to the bottom of this... not being able to use my triceps muscles sucks. I always been a good athlete and now.. I can't even do one real push up. :/
I would like to get in contact with you and hear more about your situation. It seems we are on the same boat in some form.
Athletic Built,former Marine, no other health issues besides the one explain above.
Talk to you soon,