What is Lumbosacral Facet Syndrome?
Low back pain is a widespread issue affecting many people and is one of the main reasons for disability in developed countries. It also results in billions of dollars in healthcare costs each year. Statistics vary, but it is estimated that 5% to 10% of people experience low back pain, and between 60% and 90% of people will have this type of pain at some point in their lives. Most times, low back pain resolves itself and doesn’t need more treatment than a little rest, some changes in activity, and physical therapy. About half of all low back pain cases get better in 1 to 2 weeks, and 90% improve within 6 to 12 weeks.
A condition called lumbosacral facet syndrome can cause symptoms such as one-sided or two-sided back pain that radiates to one or both buttocks, the sides of the groin, and thighs. This pain generally stops above the knee. However, it is worth noting that sometimes the discomfort from this condition can feel like the pain caused by a herniated disc or compressed roots. This condition develops due to overuse and daily activities which can lead to small instabilities and cysts around the facet joint. These changes can press on and irritate the surrounding nerve roots.
The lumbar facet joint, which is a small joint in your lower back, accounts for 15% to 45% of all low back pain, and the most common type of this pain is due to degenerative osteoarthritis. In diagnosing facet joint syndrome, the patient’s medical history and a physical exam can give useful information. Imaging tests like x-rays, CT scans, and MRIs are also used, although they often don’t show clear links between the symptoms a patient is experiencing and changes seen in the spine. To determine if the facet joints are causing a patient’s back pain, diagnostic blocks may be used, which are injections that can temporarily relieve pain. If these provide relief, interventions such as steroid injections in the joint or a procedure to destroy the nerve supplying the joint (neurolysis) may be used to address the pain.
What Causes Lumbosacral Facet Syndrome?
Lumbosacral facet syndrome, a type of back pain, can be caused by things like overuse, injury, poor posture, obesity, and wearing down of the spine over time. People tend to experience this syndrome more often as they get older. The most common cause is facet joint degenerative osteoarthritis – a kind of arthritis that affects the spine. This is usually related to the wearing down of the cushioning disks between the vertebrae in your spine. Just like arthritis in other parts of the body, this process involves a narrowing of joint spaces, loss of fluid and cartilage within the joints, and excess bone growth. It’s thought that the inflammation caused by this deterioration results in localized pain. Factors that increase risk include age, gender, facet orientation (which means the way your joints are aligned), the level on the spine (most commonly L4-L5), and a history of disk degeneration.
It’s been observed that this kind of disk degeneration is often related to heavy physical work done before the age of 20. However, the link between these kinds of changes in the spine and the symptoms of lower back pain isn’t entirely clear, and is still being debated. Sometimes, cysts can form in the setting of arthritis, which can press on the nerves, causing spinal stenosis or radiculopathy, leading to associated nerve-related pain.
Another condition, known as degenerative spondylolisthesis, occurs when one vertebra slips forward over the one below it. This is often seen in cases of facet joint osteoarthritis, and usually results from a subluxation (partial dislocation) of the facet joints that leads to the loss of cartilage and joint changes, causing instability and tension. This condition occurs most often at the L4-L5 level of the spine and is generally associated with arthritis. However, in younger patients (around 30-40 years old), spondylolisthesis can occur due to congenital abnormalities, stress-related fractures, or a specific type of the condition known as isthmic spondylolisthesis. In such cases, it’s the L5-S1 level of the spine that’s the most affected and is usually associated with instability.
Rarely, septic arthritis can also lead to facet joint syndrome. This is an infection in a joint, often caused by invasive medical procedures, tuberculosis, or in a single reported case, a type of bacteria known as Kingella kingae.
Lastly, inflammatory conditions such as ankylosing spondylitis and rheumatoid arthritis (both types of arthritis that can affect the spine) can also involve the lumbar facet joints, as these joints are synovial in nature, meaning they’re moveable joints filled with a lubricating fluid.
Risk Factors and Frequency for Lumbosacral Facet Syndrome
Low back pain is a major reason why people miss work, only second to upper respiratory tract infections. Each year, about 25 million people are unable to go to work due to low back pain and over five million are disabled because of it. Those who suffer from chronic back pain are responsible for 80% to 90% of all healthcare expenses. These high healthcare costs are due to different reasons like too much medical imaging, not getting the right diagnosis, stopping work, and unnecessary surgeries. Low back pain can also limit what a person can do and can make everyday tasks challenging, especially for older people.
Lumbosacral facet arthropathy, a type of low back pain, has varying prevalence rates. Some reports say it’s as low as 5%, while others say it can be more than 90%. The different rates could be due to different diagnostic methods used, which may include a patient’s history, physical exams, and radiology imaging. These methods, however, may not consistently provide reliable diagnoses. But what’s clear from different studies is that lumbosacral facet syndrome, another type of low back pain, becomes more common as people age.
In a 2004 study, out of 397 patients screened, 198 (or 50%) showed a positive initial response to a type of treatment called medial branch block with lidocaine. Of those 198 patients, 124 (or 31%) reported definite pain relief after getting a repeat treatment using another medication called bupivacaine.
Signs and Symptoms of Lumbosacral Facet Syndrome
Low back pain and other spine-related conditions can vary in intensity and come with various symptoms. Even for medical professionals, it can be confusing to identify the issue.
Actually, lower back pain is often linked to facet dysfunction, which mostly happens due to prolonged pain alone. Sometimes, the pain from facet dysfunction can radiate down to the lower limb just like sciatica, often described as “pseudo-sciatic” pain. This pain may extend to the buttocks, groin area, legs, or even down to the feet in some cases, depending on the affected spine’s specific levels. Pain resulting from facet dysfunction typically worsens in the morning and after periods of rest. Various factors, like exercise, certain postures, and stress on the facet joints, can initiate this type of pain. However, a doctor usually makes the final diagnosis.
Physical examination plays a crucial role in identifying the cause of low back pain. It often involves checking for visible abnormalities, identifying tender spots by palpating, and observing the patient’s range of motion. A part of this examination involves facet loading, a maneuver done by the patient. It generally induces pain, thereby indicating a possible facet dysfunction. However, this method is not entirely reliable. Tenderness in the muscles next to the spine may sometimes indicate facet dysfunction, but it’s not a specific sign.
For further evaluation of this condition, assessing lower body muscle strength and assessing sensory function in the lower body is significant. We use specific movements like hip flexion, knee extension, ankle motion, and toe extension for this. We evaluate sensory function by gently touching different parts of the lower body. Clinicians also test reflexes at the knee and ankle. A straight leg raise test is also essential. It involves lifting a patient’s extended leg while they lie on their back. This test is positive if pain is elicited when the leg is lifted less than 45°. This test, when positive, suggests a problem with the spinal disc rather than facet dysfunction causing pain. Other tests involving different hip movements can indicate problems in the sacroiliac joint or hip, rather than facet dysfunction.
Testing for Lumbosacral Facet Syndrome
Physical examinations can help doctors rule out other causes of chronic lower back pain. However, they are generally not very specific and can’t accurately diagnose low back pain on their own. For a more precise diagnosis, doctors often use imaging techniques such as X-rays, CT scans, and MRIs.
The changes in the small joints in your spine, called facet joints, due to wear and tear (also known as degeneration) can be seen in these imaging studies. The first type of imaging used in patients experiencing low back pain due to potential facet joint issues typically includes different types of X-rays. “Oblique” X-rays, images taken from an angled view, are considered the best for assessing these joints due to the way they capture the anatomical view.
However, a CT scan can offer a more detailed view of the facet joints and is therefore the preferred method for imaging facet joint arthritis. Signs of arthritis of the facet joints that are seen via CT scan might include things like joint space narrowing, bone hardness, erosion under the cartilage, thinning of the cartilage, joint capsule hardening, enlargement of the joint processes and ligament. These conditions can cause a restriction of the spinal column and the formation of bone spurs. Such changes are observed in a significant amount of patients suffering from chronic lower back pain.
While both CT scans and MRIs are good at showing changes in the facet joints due to aging or wear and tear, MRIs have the advantage of better showing the potential impact of these changes, such as the impingement or compression of nearby nerves. Studies have found MRIs to be over 90% sensitive and specific in visualizing facet joint degeneration. However, it’s important to note that there is currently no agreed-upon best method for evaluating lumbar facet joint arthritis with imaging. Nonetheless, imaging findings of degeneration have been linked with non-specific lower back pain.
Imaging can be equally revealing in patients who have symptoms and those who don’t. Therefore, these results are generally not very effective at correlating clinical symptoms with spinal degeneration. However, imaging can help rule out serious conditions that require immediate medical attention, such as cancer, cauda equina syndrome (a serious condition caused by severe compression of the nerves in the lower spine), aortic aneurysm or dissection (a tear), or fractures. Unfortunately, due to the poor correlation between history, physical exam, and syndrome of lower spine facet joints, diagnostic blocks (injections of numbing medication) are often used to confirm a diagnosis, as they can offer temporary pain relief. But, it’s recommended that this process is done twice to confirm a diagnosis due to the high chance of false positives. If you experience more than 80% pain relief after the procedure, it’s considered a positive response.
Treatment Options for Lumbosacral Facet Syndrome
Treatment for lumbosacral facet syndrome, a condition that can cause pain in the lower back, typically involves a combination of different approaches. If doctors aren’t sure about the diagnosis, they may perform diagnostic medial branch blocks. This procedure involves injecting a local anesthetic near nerves that are potentially causing the pain to see if it brings relief.
Non-surgical treatments include medications like NSAIDs, acetaminophen, and oral steroids, which are particularly helpful during painful episodes. They might also recommend weight loss and physical therapy, both of which have proven beneficial.
Minimally invasive treatments aim to reduce back pain by blocking the nerves responsible for the pain. Medical professionals consider an 80% reduction in pain and improved mobility after a medial branch block as a clear sign of facet-induced low back pain. Repeat blocks might be necessary to reach an accurate diagnosis due to high false-positive rates (30-45%) when only a single block is performed.
After successfully blocking the medial branches (nerves causing the pain), patients may opt to undergo neurolysis, a procedure aimed at destroying the nerves and stopping pain signals from reaching the brain. Since a single facet joint receives nerve supply from two areas, radiofrequency probes are used at two subsequent levels during the treatment. Radiofrequency and cryoneurolysis are common techniques used to perform neurolysis. Despite the effectiveness, it’s essential to know that permanent pain relief may not be assured as the destroyed nerve will eventually grow back, potentially causing a recurrence of pain. In such cases, the procedure may be repeated.
Another minimally invasive treatment involves injecting steroids into the painful facet joint. This provides short to medium-term pain relief by reducing inflammation around the degenerative joint. However, the use of steroids for facet joint pain is a subject of debate in medical literature. It’s worth noting that using imaging guidance during these procedures can make them more effective and safer.
Surgeries might be considered when non-surgical treatments are ineffective. This usually happens after a three to six-month trial of non-surgical methods. Surgery may also be required if a large facet joint cyst is causing symptoms. The first-line treatment for these cysts is a procedure called decompressive laminectomy. This procedure involves removing a portion of the vertebral bone to relieve pressure on the spine. In some cases, facetectomy (removal of the facet joint), decompression, and instrumented fusion (joining two or more vertebrae together) might be considered as treatment options.
What else can Lumbosacral Facet Syndrome be?
When people experience lower back pain, the cause could be a range of different conditions. These might include:
- Discogenic pain syndrome in the lower spine
- Herniated disc in the lower spine
- Lower spine facet joint syndrome
- Nerve root compression in the lower spine
- Acute bone injuries in the lower spine
- Sprains or strains in the lower spine
- Slipped vertebrae in the lower spine
- Arthritis-related changes in the lower spine
- Strains/sprains in the muscles or ligaments near the spine
- Rheumatoid arthritis
- Certain types of arthritis not detected by typical tests (most commonly ankylosing spondylitis, psoriatic arthritis, and reactive arthritis)
- Disease causing abnormal bone density
- Infections
- Cancerous growths
- Fibromyalgia
- Condition affecting the hip joint
- Muscle disorder related to the hip muscle (piriformis syndrome)
- Injury to the joint between spine and pelvis
Doctors try to find the root cause of the lower back pain by ruling out these conditions. This can be a challenge. Detailed patient history and a thorough physical examination can guide this process. For instance, if a patient’s pain seems to radiate towards their lower legs, it could point towards nerve root compression or disc related pain. Or it could suggest pain originating from a joint in the back (facet joint), especially if the person has a cyst in that joint. Examination may include tests that check hip movement and leg flexibility. These tests, along with imaging methods like X-ray, CT, and MRI scans, can provide valuable information about the spine’s structure. However, they may not definitively pinpoint the true cause of the pain. The most reliable way to determine if the pain originates from the facet joint is a medical procedure known as the lumbar medial branch block.
What to expect with Lumbosacral Facet Syndrome
The likelihood of developing Lumbosacral facet joint syndrome, a condition that affects the back and spine, increases as you get older, particularly due to its most common cause: a type of arthritis that affects the facet joints in your spine. Before considering more invasive treatments, you’d be advised to try non-surgical methods, like physical therapy, first.
If physical therapy and medication aren’t enough to manage your back pain, your doctor may recommend a procedure called a medial branch block. This involves injecting a local anesthetic near the nerves that are causing your pain. This procedure not only helps control the pain but can also confirm whether the facet joints are the source of your discomfort.
For those with successful diagnostic blocks (indicating the pain indeed comes from your facet joints), a treatment called radiofrequency ablation might be recommended. With this method, heat generated from radio waves is used to target specific nerves and reduce pain. This treatment can relieve pain for six months to a year. However, if the pain returns, the procedure can be repeated as necessary.
Possible Complications When Diagnosed with Lumbosacral Facet Syndrome
The treatments for lumbosacral facet joint syndrome typically have very few serious complications. However, one treatment, steroid injections into the joint, can carry some risks. These risks include changes in your metabolism and endocrine system, such as increased blood sugar levels and reduced communication between your brain and adrenal glands. In some cases, infections have been reported after patients undergo this treatment. These infections can potentially lead to severe conditions like an abscess near the spine, infected arthritis, or meningitis.
Some other potential side effects of spine injections include puncturing the tough outer layer of the spinal cord and temporary, reversible spinal anesthesia. Another type of treatment, radiofrequency ablation, has been found to cause neuritis (nerve inflammation) in about 5% of cases.
Note that while rare, there have also been reports of temporary numbness and strange sensations following these treatments. Extremely uncommon complications could even include burns caused by electrical faults during the procedure.
Possible Side Effects:
- Metabolic and endocrine system changes
- Infections leading to severe conditions
- Dural puncture
- Temporary spinal anesthesia
- Neuritis (nerve inflammation)
- Transient numbness or strange sensations
- Burns from electrical complications
Preventing Lumbosacral Facet Syndrome
As part of the first steps in physical therapy, patients should learn about exercises they can do at home and the right way to sit and stand to support their health. Considering the link between being overweight and having lower back joint dysfunction, discussing how to lose weight effectively can be crucial in preventing back pain. To be sure the back pain isn’t related to a more serious problem, patients should get checked by a specialist such as an orthopedic doctor, a physical medicine and rehabilitation doctor or a spine surgeon. A thorough evaluation ensures that treatment plans are safe and effective.