5.5 year old american bloodline (not show line-straight back) GSD, 105lbs with little to no fat on him. Over the weekend, he started to have some wierd movement in his hind legs that I would equate to muscle spasms. He still had his strenght, but something did not seem right. I took him to the vet first thing yesterday and they did an exam. The vet noticed that when she put a decent amount of pressure on his spine about mid way between his front and rear legs, she could get the same type of spasm. She said it could be a few things and wants to start by putting him on steriods for 2 weeks along with antibiotics in case it is an infection in his back. Also, no activities. Walks only to go to the bathrrom. I guess my question is does this sound like the normal course of treatment, or should I go straight to a specialist because it is his back? Just to give a little more info, he plays hard at least 20 minutes a day with multiple other sessions of goofing off, etc. He is not a working dog, but has a high enough drive that if he goes without hard play for 2 or 3 days, he drives me nuts. Unfortunetly, I do not have access to a pool or lake for swimming. Also according to the vet, the signs he presents do not lead them to suspect degenerative myelopathy. He still has his reflexes and feels stimulation in his toes.

Did they do plain-film xrays of his spine?

Not yet. I ask about x-rays and they said that if it was disk disease, chances are it would not show up in plain x-rays and that they would have to do the ones that inject dye or possibly a MRI. Just as an FYI, I live about 25 miles from Univeristy of Pennsylvania which has a higly regarded Vet Center. My local vet stated that I would be sent there for any type of imaging if they do not see results within two weeks. I personally thought that they would do at least the plain x-ray.

I just found this from a vet web site.
"A lumbosacral syndrome is uncommonly associated with disk disease. In some animals with lumbosacral disk extrusion, one pelvic limb may be held in partial flexion or a repetitive "stamping" motion may be observed. These animals frequently show considerable pain on manipulation of the limb and lumbosacral spine. "
He did have the stamping motion yesterday morning, but by the time we got to the vet, it disappeared. He did not show any signs of pain though which is oppistie from what most things about disk disease state.