Dr. Andrew Isaacs
DVM Diplomate ACVIM (Neurology)
Dogwood Veterinary Referral Center
Primary interests include intervertebral disc disease, seizure management, luxations/fractures of the spine, and surgery for brain tumors
What causes the hump on the back that some IVDD dogs develop?
Dogs with IVDD can have a “hump” or “bump” appearance to their back in three situations: pre-surgical (medical management), immediate post-operatively, and long term post-operatively.
If they have a painful back or neck they will assume a posture that minimizes movement of the spine. Typically, they will arch their back and bring their front and rear legs closer together in an effort to decrease discomfort. This is similar to a human with a bad back – it hurts to stand up straight so they hunch over to help relieve the pain.
Another scenario where we see dogs develop a “hump” or “bump” is shortly after IVDD surgery. First, to perform surgery the hair on the back is shaved off. This in itself will cause the spine to look more prominent. Secondly, when closing the incision the fat under the skin can bunch up and create a “hump”. A seroma (a pocket of fluid under the skin) can also occur post-operatively and create a bump. Lastly, an uncommon cause would be an infection. If you notice a “hump” right after surgery, you should contact your veterinarian and have your pet evaluated. Most of the time it is nothing to be concerned about, but it is better to be safe.
We have seen dogs that have a slight arch in their back 2 months or more after surgery. There is no definitive answer as to what is causing this. We speculate that it could be that the muscles are still healing. Part of the surgery involves elevating muscle off the bone/vertebrae and it never re-attaches perfectly like before surgery. So, the spine will be a little more prominent than before. Regardless, this is not a life-threatening problem when seen and when the hair regrows will be hardly noticeable.
If you are concerned about any bump or hump it’s best to have your veterinarian check it out.