Hello Sue
What other drugs do you take? For neuropathic pain, stiffness etc?
It could be that you need something different to Naproxen which is generally used for inflammation in joints and muscles.
If your legs are very stiff, something like Baclofen might help. You need a certain amount of stiffness in your legs (otherwise they’d not hold you up very well), but if they are very stiff something to relax them might help.
If it’s neuropathic pain, then you might benefit from Pregabalin or Gabapentin. Or Amitriptyline.
Sue