Intervertebral Disk Disease in Dogs and Cats

When an animal is presented with spinal pain of a neurological origin, there are five possible differentials for the cause of that pain. They are; intervertebral disk disease, neoplasia (of the spinal cord or surrounding structures), diskospondylitis, trauma, and myelitis / meningitis. Occasionally, other disease processes may fit into a list of differentials for spinal pain based on the signalment of the animal, such as atlantoaxial instability, cervical vertebral malformation / malarticulation, or a caudal brainstem mass, all of which may or may not present with cervical pain. Often, animals with orthopedic disease are mistakenly diagnosed with neurological disease simply because there are no radiographic demonstrable signs. Soft tissue injuries of the muscles, joints, or ligaments may be difficult to diagnose. An animal with bilateral cruciate rupture will have a gait that is very reminiscent of an animal with a neurological dysfunction. The key to differentiating neurological disease from orthopedic disease is to remember that animals with an orthopedic problem will not want to use the limb (limping or lameness), and animals with neurological problems cannot use the limb (dragging or weakness).