Facet pain is a result of the lumbar facet joint assuming an increasing weight-bearing role. Facet pain generally occurs in the setting of lumbar degenerative disc disease. Facet pain also can be associated with lumbar spondylolisthesis , which is a variation of lumbar degenerative disc disease, with associated slippage of one vertebra over another (Figure 12.1). Facet pain may be clinically indistinguishable from other types of mechanical back pain, but certain telltale symptoms and signs are present.
A patient with facet pain often develops a sudden, severe pain just to one side of midline in the lower back. Pain is relieved with trunk flexion, because this causes an unloading of the facet joints. Thus, as the patient bends forward, the facet joint opens up, which means it is no longer in a jammed position (Image 2). Pain is worsened with trunk extension, especially with trunk extension and associated trunk rotation, because this causes more facet jamming (Image 3). Pain may be referred into the buttock region and, rarely, into the leg.
Facet pain generally occurs intermittently, with attacks that can last for days at a time. In some cases, patients develop repeated facet jamming with sudden positional changes. This generally is associated with segmental lumbar instability.
Cause of Facet Pain
The facet joints are normally smooth, gliding joints that allow a directional movement of the spine based on facet orientation. In the lumbar spine, the facet joints allow trunk flexion and trunk extension. As the lumbar disc degenerates, the vertebral bodies approximate one another, leading to a loss of the normal space within the facet joints.
Normally, the facet joint is lined with smooth cartilage, so that the space between the two facet segments allows for smooth, gliding movement of the spinal joint. The facet joint complex is part of the spinal joint, and thus entails two lumbar vertebral bodies. Thus, one can talk of the facet joints at the L4-L5 level, or the L5-S1 level, or any other two-level segment of the lumbar spine.
As the lumbar vertebral bodies approximate one another, the facet joints degenerate, and the pain-sensitive structures within the joint can become irritated (Image 4). With sudden movement in a patient with lumbar instability, or with jamming of the facet joint in trunk extension, the patient can experience severe pain and sometimes will develop a reflex bending to the side or flexed forward posture.
The patient with facet pain generally can bend forward without difficulty. Upon attempting to extend backward, especially with a rotation movement of the spine, welllocalized pain develops. This pain arises from jamming and irritation of the facet joint with such movement. Sometimes, palpable tenderness is present just to the side of the lumbar spine, at the level of the irritated facet joint. Other aspects of the physical examination are largely unremarkable, unless severe, acute pain is present, in which case an associated muscle spasm is usually present. The neurologic examination is normal.
Imaging and Diagnostic Studies
Plain radiographs of the lumbar spine will reveal evidence of degenerative facet changes, especially if an oblique view is obtained. Magnetic resonance imaging (MRI) and computed tomography (CT) scans will similarly reveal degenerative changes. Generally, the facet joints become hypertrophic. Associated spurring may be present; as the joint becomes more degenerated and stressed from assuming a weight-bearing role, the facet joint develops calcium deposits that can cause more dysfunction to the joint itself.
Treatment for facet pain is very similar to treatment for degenerative disc disease. For acute bouts of pain, a nonsteroidal anti-inflammatory drug (NSAID) may be beneficial or, if pain is severe, a short course of corticosteroids may help to alleviate pain. Sometimes considerable reflex muscle spasm occurs with acute facet jamming. In this case, a muscle relaxant also will be helpful. Narcotic analgesics are appropriate for more severe pain.
Manual therapy techniques can be quite useful for facet jamming. Spine mobilization and careful spine manipulation may help to unload the facet joint. Manual physical therapy techniques similarly can help to unload the facet joints. Acupuncture may help to alleviate associated muscle spasm.
For the patient with prolonged pain that is anatomically referred to the facet joint, a facet injection may lead to considerable relief. In many ways, this injection is both diagnostic and therapeutic. A short-acting anesthetic, localized to the correct facet level, will lead to immediate pain relief. This can be coupled with a corticosteroid injection. If pain relief is obtained, then progressive physical therapy should begin, with a focus on facet unloading and spine stabilization.
Some patients may develop recurrent facet pain following a successful facet injection. If the diagnosis is secure, then a more definitive facet treatment by way of a rhizotomy may lead to more longstanding relief (see here for details). Rhizotomy procedures should be followed by progressive physical therapy to help the patient learn to stabilize the lumbar spine.
Surgical treatment for facet jamming is similar to surgical treatment for lumbar degenerative disc disease (see here). Most patients will not require surgery. For the patient who has refractory facet jamming, generally with associated spinal instability, then lumbar disc replacement or lumbar spinal fusion may be beneficial. Indications are similar to those for lumbar degenerative disc disease. The medical risks must be considered carefully.
Mind-body considerations for facet jamming are similar to those for lumbar degenerative disc disease, because most patients with facet degenerative changes are genetically predisposed to this anatomic development. Patients must be mindful that they have a degenerative lumbar spine, and they need to make appropriate adaptations, both in lifestyle and with regard to physical and psychological stress. Even patients with facet degenerative changes can have a full, active life, so long as they have made appropriate adaptations. Generally speaking, patients who follow through with a healthy exercise program and appropriate spine stabilizing exercises can do well over the long term. Stabilizing exercises such as yoga, Pilates, or t’ai chi also help patients to develop a good sense of centering and balance with regard to their lumbar spine in particular, and their well-being in general.
- Facet pain usually develops in conjunction with lumbar degenerative disc disease. The pain results from the facet joint assuming a weightbearing role rather than acting as a smooth, gliding joint.
- Forward bending often alleviates facet pain because this position opens up the facet joint.
- Treatment for facet pain is similar to treatment for lumbar degenerative disc disease. Patients may respond in particular to facet injections.
- Over the long term, spine stabilization exercises are important in helping to minimize future bouts of pain.
- Surgical indications for facet pain are similar to those for lumbar degenerative disc disease.