--can happen with certain types of peripheral neuropthy, if the motor nerves are affected; muscles may atrophy from lack of use and lack of nerve-signalling "tone".

It sounds as if you'd need a very comprehensive work-up, and a full range nerve conduction study/electromyography (EMG) would be a prominent test. And it shouldn't be done in any old office--a specialty center would be a better bet (NCV/EMG testing is notorious for wide ranging results depending on what conditions the test is done under and just who is interpreting).