Spinal Pain
Back pain can be caused by a number of conditions. It can be as simple as soft tissue injury and trauma; however in many cases it is due to spinal injury.
In this article we will discuss three conditions that are frequently associated with back pain.
Intervertebral Disc Disease
The vertebral column is part of the skeleton that extends from the skull to the pelvis. The spinal cord sits within the vertebral column which contains sensitive nerve fibers that carry information between the brain and the rest of the body, especially the limbs. The vertebral bodies are connected to each other by cartilaginous shock absorbers called intervertebral disc. These discs contain a gel-like center that is normally very flexible, and a more firm outer shell. Over time, the discs can degenerate and mineralize and bulge into their surroudings, putting pressure on the spinal cord. Ultimately, the intervertebral disc can suddenly rupture into the spinal canal putting pressure on to the delicate spinal cord. This causes spinal cord inflammation and injury. Symptoms such as pain, weakness, and even paralysis can occur as a result of this rupture process (also called intervertebral disc extrusion). The entire spectrum of intervertebral disc degeneration, bulging, and extrusion/rupture is referred to as Intervertebral Disc Disease (IVDD).
IVDD can occur as a chronic (disc bulges chronically over time and may exude disc material slowly) or acute (disc ruptures suddenly) condition. The symptoms an animal feels depend on the time frame, severity, and location of the spinal cord injury. IVDD is rare in cats.
Spinal shock
This is a temporary loss of spinal function that is generally associated with trauma. It occurs suddenly and is somewhat like a concussion of the brain. It may leave permanent damage or full recovery may occur. Recovery from spinal shock generally occurs within a few hours to a few days.Fibrocartilaginous embolism
In this condition, a small amount of disc material ruptures and gets into one of the blood vessels leading to the spinal cord. As the vessel narrows, the disc material obstructs it, depriving a certain segment of the spinal cord of its blood supply. Without proper blood supply, that segment of the spinal cord dies, resulting in paralysis. Surgery will not help these dogs because there is no pressure on the spinal cord. Often, paralysis involves only one rear leg, or one rear leg is more severely affected than the other is. Complete recovery may occur in a few days to weeks, or there may be permanent damage to a portion of the spinal cord. Diagnosis of fibrocartilaginous embolism is based on specific clinical signs and an abnormal MRI; however, early in the condition, an MRI may show no visible changes. Unfortunately, a definitive diagnosis can only be made by performing a spinal cord biopsy after death.
