Facet Arthropathy: An Under diagnosed but Treatable Cause of Low Back Pain
What are the facet joints ?
The facet joints lie on the side of the spine closest to the skin of your back. A pair of these joints can be found at each of the 32 motion segments in the human spine. These joints move with each bend or twist of the body, working in conjunction with the intervertebral disc to allow motion in the neck, trunk, and lower back.
What function do the lumbar facet joints perform ?
These joints help to restrict and control the motion of the spine. They help to guide and protect the intervertebral discs as well. In the lower back (lumbar spine) they help to constrain the amount of twisting and also keep the segments of the spine from slipping off of one another.
Why are the facet joints prone to disease ?
Because the facet joints constrain motion they are subject to significant mechanical stress. The spine of a physically active adult undergoes as many as one
million motions per year. This repetitive trauma leads to cumulative wear and tear. The facet joints allow movement between two surfaces covered with a
thin layer of cartilage, and an interposed fluid-like sac helps to lubricate any motion, just like in the knee. Microscopic injuries (tears and abrasions on
the cartilage) lead to an inflammatory process that produces pain. This is a form of osteoarthritis just like in the other joints of the body.
What are the symptoms of facet arthritis ?
Severe back pain is the most common complaint. This can be associated with leg pain that is almost indistinguishable from sciatica caused by a herniated disc. In addition, the symptoms are typically worse in the morning upon awakening and can be aggravated by bending backwards (in extension).
Facet arthritis can occur in any part of the spine but is most common in the lower back.
How is facet arthropathy diagnosed ?
Like most diseases, facet arthritis is primarily diagnosed based upon the specific nature of the patient’s complaints. In addition a physical examination is useful for eliminating other causes of back pain. Imaging studies such as X-Rays, CT scans, and MRI’s can also show evidence of the physical abnormalities in the facet joint. However, the most specific test for this disease remains a SPECT bone scan. This study involves the injection of a minute amount of harmless radiotracer into the
bloodstream. The tracer then migrates to areas of the body with excessive inflammation which can be identified through photographs taken by a specialized
Why is facet disease under diagnosed ?
There has been a tremendous emphasis on the intervertebral disc as a cause of back pain. Most patients are familiar with the concepts of herniated discs or disc bulges. However, there has been a general lack of understanding of facet disease in the medical community. This has resulted in a situation where many medical professionals fail to suspect that a patient with back pain might have facet arthropathy.
How is facet arthritis treated ?
Facet arthritis is primarily treated like any other form of osteoarthritis. Medications used to reduce inflammation are the first line of treatment. This includes non-steroidal anti-inflammatory medications as well as oral steroids. Physical therapy to mobilize and stretch the joints can also be utilized. For severe cases a direct injection of anti-inflammatory medications into the joint itself can be highly effective. This is done with a small needle under X-Ray or CT guidance and is quite distinct from an epidural injection. These, injections, while highly effective and diagnostic for the disease, provide a limited period of relief. Thus, efforts are underway to engineer facet replacement devices to treat patients with refractory symptoms. In this manner the disease will be treatable just like hip arthritis can be cured with a total joint replacement.