What is Facet Joint Syndrome?

Facet joint syndrome is a condition affecting the facet joints, which are the joints between adjacent vertebrae in the spine. This condition is characterized by pain in the back resulting from degeneration of these joints, usually via the wearing of the discs between the bones, as a consequence of osteoarthritis (OA) brought on by advanced age, certain diseases, or trauma to the joint. It may also be accompanied by the development or osteocytes or bone spurs, sometimes painful bony outgrowths along the periphery of the joint, which occur when the increased compression on the joint as a consequence of this condition causes the surface area of the adjacent bony surfaces to grow by spreading out. It should also be noted that facet joint syndrome is the name for the pain in the low back or elsewhere in the spine and its accompanying conditions. Essentially it is a symptom of joint degeneration from osteoarthritis.

Osteoarthris, also known as degenerative joint disease, is typically brought on by age. In the case of obesity, injury, or hereditary factors, however, it may be present in younger adults. It is characterized by pain, swelling, stiffness, and difficulty moving the afflicted joint. While OA may affect many of the body’s movable joints, however, facet joint syndrome is specific to the back and affects the low back in particular.

Facet joints, also known as zygapophyseal or Z-joints, are the joints between a paired structure on a single vertebra known as the superior articular process and, descending from the vertebra above it, a corresponding paired structure known as the inferior articular process. For instance, the superior articular process arising from the top of the second lumbar vertebra, L2, joins with the inferior articular process extending downward from the first lumbar vertebra, L1.

The superior articular process is a flattened surface or facet on either side of the spinous process of the vertebra, the large bony projection pointing backward and slightly downward from the body of each vertebra. Correspondingly, the inferior articular process is a slightly convex surface on either side of the spinous process situated slightly backward and downward from the inferior process, so that in their stacked position the inferior processes of the top vertebra rest against the superior processes of the vertebra directly beneath it. Together, these vertebrae form what is known as a spinal motion segment, as the synovial joints between the vertebrae allow slight individual movements that result in larger movements along the entire spinal column.

The joints between the bodies of the vertebrae allow movements like flexion, extension, and rotation, however, the Z-joints function to prevent excessive movement in the spine, thereby preventing a vertebra from slipping out of place or the pinching of the nerves exiting the spinal column. Examples of spinal movements that are limited by the facet joints include anterior shear, or forward sliding, excessive flexing, or bending forward, and extreme rotation, or twisting to the side. When these joints wear down — often as a secondary consequence of degeneration of the disks between the vertebral bodies from OA — the risk of spinal injury or nerve damage increases.

For this reason, symptoms of facet joint syndrome may include not just pain but radiating pain along the path of the affected nerve. Treatment for facet joint syndrome is treatment for its root cause of OA. It may include chiropractic and physical therapy, limiting of certain activities, and in extreme cases, surgery.