This is probably one of the trickiest neuro exam and clinical presentation of all the spinal disorders. Why? Because the books have always told us a very dramatic clinical presentation from dogs affected with a lumbo-sacral disease but the reality is that dogs can show very different degrees of neurological disfunction.

What can you see on this video?On this video you see weakness, even better, you see the dog being stiff and being lame. And this is a very typical finding of a low lumbar pathology affecting the sciatic nerve, because it’s very painful. Severe PAIN is the main sign of any compressive/inflammatory disease affecting the lumbo-sacral area.

Is that an orthopaedic lameness or a nerve root signature? This dog has clearly a problem of the right hind and he doesn’t want to put any weight on it. Before we do the full neuro exam we could even think this could be an orthopaedic lameness, as instead of dragging is avoiding to put weight on.

However, the proprioception is slow, but it’s at the same time difficult to assess, as you see the dog doesn’t want to put weight on the right hind limb. To asses properly the proprioception we must allow some weight on the limb so the brain feels the paw must be re-addressed. You can observe the vet trying to shift the dog’s weight on the right hind limb so we can observe the proprioception is slow.

Spinal reflexes on a lesion affecting the L4-S1 segment or the sciatic nerve should be “in theory” reduced, therefore on a lesion affecting the lumbo-sacral junction the withdrawal should be reduced. The withdrawal reflex in this video is indeed reduced. The withdrawal reflex asses the sciatic nerve which spinal cord segment is L6-S1. But you know dogs don’t read books, and you might find dogs with a LS disease with a normal withdrawal….don’t ask me why, but it will happen, so we need to learn how to recognize other symptoms of LS disease.

The cutaneous trunci reflex is normal. The cutaneous trunci only help us localising a problem affecting C6T2 or T3L3, so it’s expected to be normal on a LS disease.