keep in mind that a metabolic issue will not concentrate in the legs.
Most metabolic issues are more global.
If your symptoms are mostly in the legs, I'd look to the spine and compressions that may be there.
Also do not assume that your thyroid medication is working properly....it might need some fine tuning.
If you can, get a fasting insulin test...to see if you are insulin resistant. When insulin can not get glucose into muscles they do get weak feeling. Elevated insulin is the first sign of insulin resistance and impaired glucose tolerance. It is a better predictor than fasting glucose tests.
Sometimes there are no answers in the beginning. It may take time to find out what is causing your problems. Osteopenia in a male of your age is just not common. I'd focus on that for now.
__________________
All truths are easy to understand once they are discovered; the point is to discover them.-- Galileo Galilei
************************************
.
Weezie looking at petunias 8.25.2017
****************************
These forums are for mutual support and information sharing only. The forums are not a substitute for medical advice, diagnosis or treatment provided by a qualified health care provider. Always consult your doctor before trying anything you read here.