It would be reasonable to have an evaluation with a neurologist before proceeding. They can examine you and review your history. They may want to perform an EMG test (muscle and nerve test) to help determine what is occurring. Also, the last change in your CK is not dramatic, and may be within the normal variation for the lab. Let me explain, when a test is performed on the same sample at two different times, or on two different machines there is typically same variation in the result. This is the machines standard deviation. Therefore, the change from 332 to 360 may not be significant. Second, your physical activity ( excercising or hard work) prior to the test can also change the results.
Regarding the location of the biopsy, we typically try to biopsy a region of muscle which is mild-moderately involved if possible. The EMG test can be used as a guide to which muscle can be biopsied. Good luck.
Thanks much for the advice. I contacted my physcian and he agreed that it would be a good idea to consult with a neurologist before getting the biopsy.