I later took Baron to another vet and he diagnosed Baron as having Spondylosis. He has continued to get worse. The drugs have had no affect. I am not familiar with the medication sphingolin. I don't think that changes my impression of the situation, though.
German shepherds are very prone to degenerative myelopathy.
This is a condition in which the myelin sheath around the nerves degenerates, making it difficult for the nerve transmissions to get from the brain to the muscles. A progressive weakening of the rear legs occurs. It closely resembles the symptoms of hip dysplasia and can be very difficult to distinquish from hip dysplasia. Other possible problems include spinal cord damage or tumors and other neuromuscular disorders. Spondylosis only rarely causes clinically apparent lameness.