Hello. Thank you for asking your question. My name isXXXXX will try to help.
If there is any chance she has been exposed to tick, I would have her tested for Lyme's disease. It can cause stiffness and shifting leg lameness. Your vet can do an in house test to see if she has been exposed. The treatment is an antibiotic called "doxycycline."
At ten years of age, she could also e developing some arthritis in her hips, spine, or legs. It can be diagnosed with an exam and x-rays. There is not cure but it can be treated with pain medication and medications which help lubricate the joints so the cartilage does not grind.
Shaking can be caused by pain in general or muscle pain due to weakness in the joints.
Neurologic disease, or nerve inflammation, can cause shaking as well.
But first, I would rule out Lymes disease and arthritis.
I hope this helps.
If you have additional questions, please click "reply."