I don't know the product but know there are over the counter dog joint meds for dogs, see them advertised and generally available at pet supply sellers.
The product BUTE is used for cattle and horses, other livestock for
laminitis, it is a pain reliever and comes in a tube, the one I used was
a paste but I used it on my horse when she pulled a muscle/tendon
in her leg but this was what MY VET told me to use for her as well as
doing other things.
Don't know if it would be a good thing for a dog, seems if I read this
post right your dog is having problems walking, pick up one foot then
shift and walk with the other?
It's hard to say what is going on without an exam by a vet as it may be
a problem in his legs(?) or in his back which can also cause a problem
walking. No way to know without a manipulation or possible X-ray(?)
sorry couldn't help more best thing would be see your vet as this might
progress and become worse over time.
Also another thought, could she have gotten a cut on her pads or some
other thing caught in between the pads of her feet? Your fur kid is also
getting up there in age so she might have a touch of stiffness in her
joints so many things to consider.
Please let us know how things go after you see your vet and how she is