Facet joints are joints between the processes — the bony projections that protrude out from the sides of the vertebrae — that form links between adjacent vertebrae of the spine. These joints are synovial joints, meaning that they have fluid-filled joint cavities, surrounded by tendons and ligaments.
Facet joints function to guide and limit movements in the spine, and to contribute to stability during movements. Because there are distinct, structurally different regions of the spine, these joints allow different types of movement depending upon their location within the spine.
For example, facet joints in the thoracic region allow for rotation — think about turning your torso from side to side — while those in the lumbar region, often referred to as the lower back, allow flexion and extension, such as would be needed when bending at the waist.
While there are a variety of conditions that can trigger facet joint pain, the pain itself is generally caused by pressure in the joint cavity often the result of degeneration of the intervertebral discs. This is a process by which the cartilaginous discs between the vertebrae degrade and lose substance.
This loss of mass of the discs results in compaction of the intervertebral space and a misalignment of the facet joints associated with the vertebrae. The misaligned joints eventually sustain damage, leading to erosion of cartilage on the articulating surfaces and formation of bone spurs. Pain, inflammation, and loss of function follows.
Symptoms associated with facet joint pain are:
- Difficulty performing movements associated with facet joints such as twisting or bending.
- More pain when bending forward than backward.
- Muscle guarding — a condition where muscles tighten and freeze in order to protect injured joints.
- Pain, numbness and muscle weakness.
- Instability of the spine.
Although degeneration of cartilage is a natural part of the aging process, there are several risk factors — other than age — that predispose individuals to facet joint pain. These include obesity, poor posture and improper lifting of heavy objects, and genetic factors.
In addition, accidents that cause trauma to the vertebrae, and injuries that cause repetitive stress to the spine such as those sustained when lifting or bending, are prone to causing chronic facet joint pain. In people over 50, facet joint pain is usually a result of degeneration due to aging, while in younger people it typically results from injuries to the spine.
What can you do if you have facet joint pain?
Most treatments for chronic facet joint pain focus on alleviating the symptoms, and many options such anti-inflammatory medications or muscle relaxers provide temporary relief though the pain may return once the medication is stopped.
If conventional treatments fail to give long-term manageable relief, your doctor may suggest platelet-rich plasma (PRP) injections. This technique uses platelets — small cell fragments that circulate in the blood, and harnesses their natural ability to promote healing and tissue repair.
Within platelets are small granules that contain various growth factors that promote cell division and growth — two essential processes needed to heal damaged tissue.
Although platelets normally circulate in the blood and become active, releasing their potent growth factors when they encounter injured tissue, areas inside joint cavities are not able to reap the benefits of this natural healing process because cartilage tissue (the tissue that makes up synovial joints like facet joints) lacks blood vessels. PRP injection conveys the healing power of platelets to affected facet joints.
What to expect during the PRP procedure
The whole process from start to finish takes around an hour and can be done as an outpatient. In order to create the platelet enriched plasma, blood is drawn from the patient in a procedure similar to getting blood drawn for routine lab tests.
Human blood consists of several components: red blood cells, white blood cells, platelets, and proteins all suspended in a liquid called plasma. The procedure uses two of the components — platelets and plasma. In order to enrich for these components, the blood is centrifuged after collection.
A centrifuge is a piece of laboratory equipment that uses centrifugal force to pull the more dense components toward the bottom of the rotor, allowing lighter — less dense — components to remain near the top.
Once blood is drawn, it is placed in vials in a centrifuge and spun at high speeds to separate out the denser red blood cells from the less-dense white cells and platelets, leaving the least dense layer containing plasma at the top. The platelet layer is then combined with the plasma to form platelet rich plasma.
The PRP is injected directly into the facet joints using a needle similar to that used to draw blood. As with other injection procedures involving the spine, an imaging technique called fluoroscopy allows visualization of the needle and precise placement of the injections.
Most patients report mild discomfort during the injection, and your doctor may use a topical anesthetic to help alleviate this. After injection, the needle is removed and the patient will rest shortly before being able to go home.
Post PRP injection care and facet joint pain relief
Immediately following treatment and over the next few days, you may experience pain at the site of the injection. Over-the-counter analgesics such as acetaminophen may be used, but non-steroidal anti-inflammatory medications like ibuprofen should be avoided both immediately before and during treatment. Ice can be applied for pain and swelling.
During this period, the patient should rest, limit physical activity, and avoid strenuous exercise and heavy lifting. After 2-3 days and up to 2 weeks post-injection, the goal is to increase tolerance to daily activities, and your physician may advise daily stretching and range-of-motion exercises. A regimen of physical therapy may be used along with PRP as part of a comprehensive treatment plan.
PRP harnesses the body’s healing process, and some time is needed to affect restoration of the joint tissues. Most patients begin to feel some relief during the 2 or 3 weeks after the first injection, but full treatment typically requires anywhere from 2 to 6 injections, with 4 to 6 weeks of healing time in between.
PRP offers minimal risks as a treatment for facet joint pain, and since the patient’s own blood is used, there is no chance for rejection or allergic reaction. While any procedure involving injections carries a risk for bleeding and infection, this risk is very low, and complications are rare.
Physicians may recommend platelet-rich plasma as a treatment for chronic facet joint pain after conventional treatments have not been effective. It is a convenient, minimally-invasive procedure that alleviates pain by promoting repair of damaged tissue.