I apologize. I sent you a request for additional services in error. I meant to check and see if you still needed help. I suspect that your dog is having disc issues.
An intervertebral disc that has slipped or ruptured up into the spinal canal causes inflammation of the spinal cord, which in severe cases causes paralyses of the rear legs. You can read about this here:
Basset hounds are prone to disc issues and the pain of a slipped or ruptured disc will cause pain and trembling as well as possible paralyses depending on the degree of inflammation and injury.
If the metacam is not working you will need to resee your vet and discuss other options such as surgery if he is a good candidate for surgery. If you wish to answer my request for more information, I can see if that will affect my answer.
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