Welcome! My name is Dr. Andy. I am a 2003 graduate from UC Davis, and currently a Medical Director of a veterinary hospital.
I am sorry to hear about this concern for Rupert.
Good that you asked the question.
Well, you likely won't be able to cure it. Why?
The knuckling you are describing could quite possibly be what we call a loss of "conscious proprioception". Vets do a test to assess for spinal problems called testing "conscious proprioception." With supporting the body, if a pet's paw is flipped over into a knuckled position, and they don't turn it back over, that suggests a spinal problem like a disc herniation somewhere in the spine.Disc Herniation
So, your next step must really be a vet visit to assess the C.P.'s in all the legs, and possibly some spinal x-rays if your vet agrees with me.
Supportive medication is usually steroids or non-steroidal anti-inflammatories, and pain medication as needed.
Sometimes, if the paw is being rubbed badly, we'll keep a boot on them just to help protect the paw for the long term.
I hope that information has been helpful.
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