Isn't 10 years a little young for such an advanced case of spondylosis? I wouldn't expect to have a dog losing control in the rear until they are 12 or 13.
My first champion developed this at about 10 years of age. He was stiff, slow to rise and finally couldn't get up. My vet had diagnosed him with spinal spondylosis after x-rays.
As for the OP, it does sound like something neurological. I'd recommend x-rays as a start.
A grand daughter of my CH I have now is just over 10 and has displayed restricted movement on her front and later it spread to her rear. At first acupuncture and homeopathic treatments resulted in no significant improvement. X-rays revealed problems in her c-spine, pressing in on her spinal cord. Surgery, MRI's may help the problem, but at her age, we just decided to try prednisolone. She is 110% better just on pred alone.
Isn't 10 years a little young for such an advanced case of spondylosis? I wouldn't expect to have a dog losing control in the rear until they are 12 or 13.