What is spinal instability?

Clinical instability is an important cause of low back pain. As we get older, our discs degenerate and lose tension, which allows them to bulge and thus permitting an increase in movements to appear between the vertebrae. Pain appears when flexion or extension causes the vertebrae to slide forward and backward, or rotate abnormally.

This irritates the nerve, which has become tethered to the disc, vertebra, facet joint margin and ligaments in the foramen, and cannot move freely. Because the nerve cannot accommodate the abnormal movements, it will cause back and/or leg pain, arthritic overgrowth of the joints and it will lead to the development of bone spurs. Other symptoms of spinal instability include:

• stabbing pain
• spasms
• locking up of the back

Once a disc is no longer able to function normally, the degeneration process of all parts of a spinal segment begins. Diagnosis starts with a complete history and physical exam, during which your doctor will check how your back works through various types of motion. In order to correctly diagnose your problem, you may be asked to wear a back brace for a period of time to see whether it provides any relief for your pain. Other diagnostic tests that may be performed include:

• X-rays of the spine taken in the neutral (standing straight) position and at different degrees of flexion
• CT scan for observing vertebrae, facet joints and to discover any bone spurs that may be present
• MRI to check for lesions, such as a herniated disc
• electromyogram (EMG) to check for signs of segmental instability

Conservative treatment is recommended if you have been diagnosed with spinal instability, and includes the use of a special brace to support and stabilize your spine, physical therapy and stabilization exercises. Surgery is reserved for patients with severe instability when conservative treatments failed to provide positive results and pain relief.