Osteoarthritis (degenerative arthritis) can cause breakdown of cartilage between the facet joints. When the joints move, the lack of cartilage causes pain as well as loss of motion and stiffness.
The facet joints are located in the back portion (posterior) of the spine. The joints combine with the disc space to create a three-joint complex at each vertebral level. The facet joint consists of two opposing bony surfaces with cartilage between them and a capsule around it. The joint also has fluid lubricating it.
The combination of the cartilage and the fluid allows the joint to move with little friction. However, facet joint arthritis causes the cartilage to breakdown and the joint movement is associated with more friction. The patient loses motion and, as they get stiffer, they may have back pain.
Pain related to the facet joints is typically made worse by stress to these joints. Typically, the low back pain is most pronounced first thing in the morning. The pain may be increased by backwards arching of the spine such as hanging clothes out on a clothesline, for example, or walking down stairs or an incline. Throughout the day, normal movement causes fluid to build up in the joint and it becomes better lubricated, which decreases the pain. Later in the day the pain typically becomes worse again as more stress is applied across the joint.
The pain is typically most severe when standing and least severe when sitting as the spine becomes more flexed in this position and stress is taken off the joints. Similarly, when pain from prolonged standing or walking worsens patients tend to lean forward to relieve pressure on the facet joints. Sometimes this may lead to the use of a walking stick. Often the pain is situated slightly to the side of the middle of the spine and it may be possible to identify which joint in the spine seems most problematic through various x-ray tests.
Surgery is rarely effective for back pain related to arthritis of facet joints. Unlike hip replacement and knee replacement operations which have been very helpful in addressing arthritis of these joints, there is no generally accepted surgical option which is effective in treating facet joint osteoarthritis. Also, facet joint osteoarthritis commonly occurs at multiple levels of the spine which would make surgery far more extensive and less effective.
Treatment of this condition usually involves non-operative measures such as anti-inflammatory medication, a regular exercise program, lumbar corsetry and supports and, in some cases, radiologically guided injections of small quantities of local anaesthetic and corticosteroids into the affected joint. These injections may serve two purposes – assisting with the diagnosis and helping the pain.
Conservative treatments that concentrate on maintaining motion in the back are most effective for relieving the pain.