What is Lumbosacral Radiculopathy?
Low back pain is one of the most common complaints related to muscles and bones that doctors hear about. In fact, in the developed world, it’s one of the main reasons why people under the age of 45 become disabled. It’s second only to the common cold for causing people to miss work. Furthermore, treating low back pain costs society a significant amount of money each year.
While studies may offer different numbers, it’s estimated that over 5% of people experience low back pain at any given time, and between 60% to 90% of people will experience it at some point in their lives. Thankfully, many instances of low back pain get better on their own without needing medical treatment. Roughly half of cases get better within 1 to 2 weeks, and 90% get better within 6 to 12 weeks. Because there are many things that could potentially cause low back pain, doctors must consider a range of possible diagnoses. One common cause to consider is a condition called lumbosacral radiculopathy.
Lumbosacral radiculopathy is a type of pain syndrome caused by the pinching or irritation of the nerve roots in the lower part of the spine (the lumbosacral region). This often happens due to changes in the spine that result from aging, such as a herniated disc, changes to the ligamentum flavum (a ligament in the spine), an overgrowth of the facet joints (joints in the spine that allow it to bend and twist), and spondylolisthesis (when one vertebra slips out of place onto the one below it). These conditions can all lead to the pinching of one or more nerves in the lower spine.
The symptoms of lumbosacral radiculopathy often include low back pain that radiates into the lower limbs in a pattern that corresponds to the affected nerve root. Additional symptoms can include numbness, weakness, and a loss of reflexes. However, even if these additional symptoms aren’t present, it’s still possible to have lumbosacral radiculopathy.
What Causes Lumbosacral Radiculopathy?
When a spinal nerve root gets irritated, it can cause abnormal nerve signals that are felt as pain, numbness, and tingling. If it gets bad enough, it can even cause weakness along the path of the nerve. The most common causes of these symptoms, known as lumbosacral radiculopathy, are either damage to the spongy discs between the vertebrae of the spine (intervertebral discs) or age-related degeneration of the spine.
Over time, these intervertebral discs can dry out and become fibrous, making them prone to splitting or tearing. This increases the risk of disc material pushing out from its usual place in the disc space, a condition known as a disc herniation. If this happens, it might press on one or more nerve roots, leading to lumbosacral radiculopathy.
In severe cases where a large disc herniation is pressing on several nerve roots, patients can develop a serious condition called cauda equina syndrome. Besides age-related changes, anything that irritates spinal nerve roots can lead to lumbosacral radiculopathy.
Risk Factors and Frequency for Lumbosacral Radiculopathy
Low back pain is a frequent issue impacting 60% to 90% of people in their lifetime, with 5% to 10% experiencing a condition involving nerve damage known as radiculopathy. It’s a significant cause for referrals to specialists like neurologists, neurosurgeons, or orthopedic spine surgeons. It’s second only to upper respiratory tract infections as a reason for missing work. In fact, about 25 million people do not go to work due to their low back pain, and over 5 million people become disabled because of it. This condition causes a large increase in healthcare costs. There are specific risk factors that can lead to worsening lumbar (lower back) conditions, such as smoking, genetic factors, and frequent physical trauma.
- Low back pain affects 60% to 90% of people in their lifetime.
- 5% to 10% of those with low back pain will have radiculopathy, a condition involving nerve damage.
- Low back pain is a common reason for seeing specialists like neurologists, neurosurgeons, or orthopedic spine surgeons.
- It’s the second leading cause of people missing work, after upper respiratory tract infections.
- About 25 million people miss work due to lower back pain, and more than 5 million are disabled from it.
- This condition significantly adds to healthcare costs.
- Smoking, genetic factors, and frequent physical trauma are known risk factors for worsening lower back conditions.
Signs and Symptoms of Lumbosacral Radiculopathy
Lumbosacral radiculopathy is a condition affecting nerves in the lower back and can be diagnosed with a complete medical history and physical examination. The most common symptom is pain, but patients might also feel numbness or weakness in certain areas of the body that are controlled by the affected nerve. These pains are often described as “electrical shocks” or “shooting pains” and follow the path of the nerve. It’s crucial to look for any serious symptoms that could indicate a dangerous condition that needs urgent treatment.
Before assessing a patient, doctors need to check for serious symptoms often referred to as “red-flag” symptoms. These may signal more severe underlying conditions that require immediate medical attention. They include:
- Pain in the middle of your back
- Fever or unexplained weight loss
- Use of drugs injected into the veins
- Weakened immune system
- Long-term use of steroids
- Night sweats
- Problems with bowel or bladder function
- Cancer
Past surgeries, treatments such as chemo or radiation, recent medical imaging, bloodwork, or history of cancer spread should also be noted. Certain signs like pain at night, unexplained weight loss, or night sweats, can accompany these symptoms. Neurologic issues, declining health, balance problems while walking, numbness in the pelvic region, sudden urinary problems, increasing weakness in the lower body, and age of onset (younger than 20 or older than 55) should also be considered.
A full neurological examination is also performed. This includes various physical tests to assist in diagnosing lumbosacral radiculopathy. For example, the Lasègue test involves lifting one leg to create tension on the sciatic nerve, and the straight leg test checks the femoral nerve and the L2 to L4 nerve roots. These maneuvers, along with others, can provoke symptoms and help identify the problem.
In cases of lumbosacral radiculopathy, patients might display diminished deep tendon reflexes. For instance, the reflex in the knee could be affected in case of L4 nerve root problems, the medial hamstring reflex for L5, and the Achilles reflex for S1. Muscle weakness usually influences certain muscle groups, this could be the quadriceps femoris for L4, the tibialis anterior for L5, and the gastrocnemius for S1. Sensation might also be decreased in certain areas: the inside of the ankle and foot for L4 sufferers, top of the foot for L5, and the outside of the ankle and foot for S1.
Testing for Lumbosacral Radiculopathy
When a person experiences low back pain and lumbosacral radiculopathy (which is a condition where nerves near the bottom of the spine are irritated or compressed), it’s often not necessary to do detailed imaging tests if their symptoms have been present for less than 4 to 6 weeks. This is because these symptoms often improve on their own. Instead, doctors will usually start by carrying out a thorough physical examination.
If the physical examination reveals neurological deficits – which means problems in the brain or nervous system – especially particular types of muscle weakness, then the patient might need additional assessment. If the pain persists for 1 to 2 months despite conservative treatments (which usually means non-surgical treatments like physical therapy or medication), then a type of scan called an MRI (Magnetic Resonance Imaging) can be done. This scan, which doesn’t involve any contrast dye, is considered the best method for evaluating lumbosacral radiculopathy.
In some cases, contrast is used with the MRI, particularly if the doctor needs to rule out an infection. This is especially true for patients who have had spine surgery in the past.
There’s an alternative imaging test called a CT (Computed Tomography) myelogram, which is helpful for patients unable to undergo an MRI. However, a CT scan is not as good as an MRI at seeing soft tissues or tumors, so it’s not commonly used for these types of assessments.
X-rays are another imaging technique that are widely available and easy to do. X-rays can show noticeable abnormalities in the bones, like fractures, spondylolisthesis (which is when a vertebra – one of the small bones in your spine – slips forward onto the bone beneath it), loss of disc space, and other changes related to ageing. However, if the findings of the x-ray don’t quite fit with the patient’s symptoms, then a type of test called electromyography (which measures muscle response) and nerve conduction studies (which evaluate the passing of electrical current through the nerves) might be required. These tests are good at accurately locating a problematic nerve out of many possible ones.
Treatment Options for Lumbosacral Radiculopathy
Treatment for this condition differs based on the cause and seriousness of symptoms. The first step usually involves managing symptoms in a non-invasive way. Medications can be used to control pain, such as nonsteroidal anti-inflammatory drugs (NSAIDs, like ibuprofen), acetaminophen (like Tylenol), medications typically used for seizures but have shown effectiveness in treating nerve pain (such as gabapentin), and in severe cases, low-dose opiate-based painkillers. If you have lumbosacral radiculopathy, a condition where a nerve root in the lower spine is inflamed or damaged causing pain, numbness, or weakness in the legs, steroid medications may be used to provide some relief.
Aside from medications, other non-drug treatments can also be beneficial. These can include physical therapy, acupuncture, chiropractic adjustments, and traction, which is a type of therapy that uses a system of weights to relieve pressure on the spine. However, it is fair to note that the effectiveness of these methods still needs more clear research evidence.
Medical procedures could also be used to help manage the condition. These can consist of injections of steroids into the space around the spinal nerves (known as an epidural), or a minimally invasive surgery called percutaneous disc decompression, which involves reducing pressure on a spinal disc.
In cases where the common methods of treatment aren’t working, surgical options could be considered. These could involve decompressive surgery, where part of the spine is removed to relieve pressure on the nerve roots, or a procedure called a fusion, where two or more bones of the spine are joined together if they have become unstable.
What else can Lumbosacral Radiculopathy be?
When a doctor is figuring out the cause of pain radiating from the lower back area (known as lumbosacral radiculopathy), there are many possible conditions they might consider. These include:
- Problems caused by wear and tear on the spine, including shifted vertebra, narrowed spinal cord, or damage due to repetitive minor injuries (most common causes)
- Damage from sudden, serious injuries, which could be a spinal fracture due to accidents or in the elderly, fractures caused by weak bones due to conditions like osteoporosis
- Tumors, either those that start in the spine or those that have spread from other parts of the body
- Infections, which can affect the bones or discs in the spine, cause abscesses, or be a symptom of other conditions like Lyme disease or HIV/AIDS
- Vascular conditions, which are diseases affecting the blood vessels
- Inflammation in parts of the body near the spine, like the hip
- Conditions affecting the peripheral nerves
- Conditions that a person is born with, that can create abnormal connections between the nerve roots in the spine
- Conditions that develop after birth, like cysts near the joints in the spine or calcifications in the surrounding tissues
Because there are so many possibilities, it’s essential that they thoroughly examine the patient to find the true cause.
What to expect with Lumbosacral Radiculopathy
In most instances, lumbosacral radiculopathy, a condition where nerves in the lower back and hip area are compressed or irritated, can be managed successfully without surgery. However, for those cases where surgery is necessary, one study found that out of 100 patients who underwent a type of surgery called a discectomy, 73% reported total relief from leg pain and 63% experienced no more back pain after one year.
These positive outcomes remained consistent even five to ten years after the surgery, with 62% of patients still reporting complete pain relief. It’s noteworthy to mention that only 5% of the patients had what is known as “failed back syndrome,” which means their pain and symptoms didn’t improve even after surgery, five to ten years later.
Possible Complications When Diagnosed with Lumbosacral Radiculopathy
Surgical treatment for lumbosacral radiculopathy, or sciatica, can potentially lead to various complications. These can include superficial wound infections, which affect between 1% to 5% of patients. Other risks can involve an increase in motor deficit or unintentional puncturing of the dura mater, the outermost layer of the spinal cord. In a 10-year follow-up study, 4% of patients experienced a recurrence of herniated lumbosacral disc. Additionally, patients may have difficulty urinating post-surgery.
Common Risks:
- Superficial wound infections (1% to 5% of patients)
- Increased motor deficit
- Unintentional puncturing of the dura mater
- Recurring herniated lumbosacral disc (4% with 10-year follow-up)
- Difficulty urinating post-surgery
Preventing Lumbosacral Radiculopathy
Lumbosacral radiculopathy is a medical term for a type of pain that comes from nerve irritation or pinching in the lower part of your back. It’s known to cause lower back pain, leg pain, numbness or a tingling sensation in the legs, and weakness. It’s usually due to changes in the body that happen naturally as we get older.
Often, the pain and discomfort associated with this condition can be treated non-surgically. Treatments can include medications, non-drug treatments such as physical therapy, and specific pain treatments like special injections.
That said, if these non-surgical treatments don’t work and you are still experiencing pain or discomfort, further tests using imaging techniques might be required to get a clearer image of what’s happening inside your body. In some cases, surgery might be necessary.
If you think you’re experiencing symptoms associated with lumbosacral radiculopathy, it’s a good idea to get checked by a healthcare professional to rule out severe symptoms. It’s very important to diagnose and treat conditions associated with these symptoms as soon as possible to avoid more serious complications.
