Many people are surprised to find out how similar human anatomy and physiology is to that of our dogs and cats. There are obvious differences such as walking on four legs, having sharp teeth for killing, and tails; however, the overall makeup and function of our bodies are much more similar than different.
One very common trouble spot for both people and dogs is the spine. Back and neck pain is a problem for millions of Americans, and a regular problem we see in dogs. The tricky thing, of course, is that a dog doesn’t come in telling us where it hurts. However, by reading some classic clinical signs along with a decent physical exam, we usually diagnose this problem fairly easily.
The most common problem we see with the spine in dogs is intervertebral disc disease, “a herniated or slipped disc.” Our spine is made up of many individual bones called vertebrae. A ton of ligaments and muscles connects the chain of vertebrae to make it a flexible, yet very strong column to which the head and arms and legs attach. Between each vertebra is a “disc”—a small, strong, flexible cushion that helps absorb shock as the spine bends and compresses. Each is like a tough jelly donut—a squishy inside and a tough outside. Running directly through the middle of each vertebra is the spinal cord.
The spinal cord is essentially the highway that all control of movement and perception of feel runs through. It is such an important structure that the body will send a very strong alarm signal (PAIN!) if it is being pinched or compressed.
Intervertebral disc disease (IVDD) is when disc material ruptures out and starts compressing the spinal cord directly above it. There’s very limited space around the spinal cord so it doesn’t take a lot of disc material to cause a lot of problems. IVDD can range from mild, where there is mild compression and just pain, to severe, where the animal is essentially paralyzed downstream from the disc herniation.
For most dogs with IVDD, the disc has simply been weakening with age. One day the dog does a relatively normal activity, like jumping off the couch, and suddenly the disc ruptures, its contents punching the spinal cord.
“Mitzi” was an 8-year-old Dachshund brought in recently for “acting sick and yelping in pain.” She had been totally normal the week prior, the owner told me, but over the weekend she was trembling and just not acting right. She wasn’t eating well and would randomly yelp out in pain.
This was not only the classic history of a herniated disc but also the classic breed. Dachshunds and other “short long” dogs are the ones we see most commonly.
I examined Mitzi carefully. She was in a lot of pain. Fortunately, she was walking, but when I pressed down on her back, she immediately yelped as if I had stabbed her.
Mitzi was a relatively mild case. She had a recent herniation but was walking just fine. Dogs like her typically recover without surgery, just time and some anti-inflammatory pain medications. However, once a dog has one disc herniation, he is very likely to have another.
“Jimmy” was more severe. He was a lab mix who presented for not being able to get up that morning. When Jimmy came in, it was hard to tell if he was in a lot of pain or if he was just really anxious. He was panting heavily and trembling, but I could not get him to yelp. Jimmy could not use his back legs at all, even if we placed his legs under him. He sat in an awkward position as if he couldn’t feel his rear legs. In fact, he couldn’t. In a seemingly cruel test, I squeezed Jimmy’s toe as hard as I could. He didn’t notice.
His spinal cord was so severely compressed that he could not move or control his rear legs. Jimmy needed immediate surgery. If we waited, the damage to the spinal cord might turn permanent. A specialty veterinary surgeon performed an MRI to tell exactly where the herniation was, and then removed the protruding disc material from the spinal column.
There are several variants of intervertebral disc disease, but these cases demonstrate the most common ways we see it. One of the telltale signs of disc disease is the intermittent yelping out in pain. Actually, not much else causes dogs to do this without being actively in a fight or trauma. They typically yelp when their owners try to pick them up or sometimes when they are lying down. If you see your dog doing this and just not acting right, it’s time for a visit to the vet ASAP.
Dogs who lose function of their rear legs are more obvious, and that is always an emergency. The difficult thing with these cases is that the surgery is prohibitively expensive for most people. Some of these dogs respond to steroids and cage rest, so it’s always worthwhile bringing them to your vet immediately.
I don’t wish back pain on any person or dog. It is, unfortunately, a fact of life for many. With good treatment and possibly some lifestyle changes (losing weight, no more Frisbee, etc.), we can usually get pets back on their feet and wagging their tails again.