Lumbar Radiculopathy refers to damage or irritation of nerve roots that exit the lumbar spine or low back. This is commonly referred to as a ‘pinched nerve’. At each vertebral level in the lumbar spine, a nerve exits and travels in a specific path to the skin and muscles of the legs. Generally, these patterns are the same for all people although there can be slight variation. We refer to this specific map of nerves as dermatomal patterns.
Nerves are responsible for these three main functions: pain, sensation and strength. Pain is usually the first sign of nerve irritation and may be felt many different ways such as a deep, dull, and achy pain or a sharp, shooting pain along the path of the nerve affected. Sensation changes tend to occur first as pins and needles or tingling and can progress to numbness. Strength changes may be subtle in certain muscle groups or be quite noticeable. Because the nerves are responsible for these functions, compression (or ‘pinching’) of a nerve may result in pain, sensation changes, or weakness at different parts of your legs.
How does this happen? Nerve roots that exit your lumbar spine can be compressed by several ways. Degeneration of the discs in the spine or bone spurs associated with arthritis can both cause these symptoms of radiculopathy.
Disc Herniation: A disc herniation occurs when a tear in the outer ring of the disc, called the annulus, allows central material of the disc, called the nucleus, to squeeze through the tear. The annular tear can happen at any place in the outer ring of the disc. Because the spinal canal is home to the spinal cord and nerves, the extra material can place pressure on the nerves. The disc material itself is very acidic and causes a chemical burn or irritation to the surrounding tissue. Together, pressure changes and an acidic environment can cause inflammation of the nerve roots and lead to radiculopathy.
Bone Spurs: Bone spurs form over time in response to arthritis or degenerative changes. Bone spurs can occur anywhere on the bone. When they form inside the foramen (or hole) where nerves exit through, this reduces the normal space available for a nerve root to “live” and causes irritation to the nerve. We call this foraminal stenosis. A nerve root being pinched by a bone spur can cause the same symptoms as a herniated disc since both processes can cause nerve irritation as the nerve exits the spinal canal.
Usually, a careful physical examination will identify the source of the symptoms. Your doctor will perform a throughout history and physical exam to understand your condition. Your exam will include neurological tests that will assess sensory changes, strength changes, reflexes and specific tests that may produce your pain. Certain exam findings may show the cause of your symptoms and identify which nerves are involved. Diagnostic tests are also used in addition to the physical exam and may include x-rays, a lumbar MRI, and/or an EMG of your legs depending on what your exam findings show.
There are many different treatment options available for radiculopathy; recommendations depend on your level of pain, length of symptoms, and degree of abnormal findings on exam. Medications are commonly used to reduce inflammation, control pain, and manage any resulting muscle spasms. You may be prescribed a short course of oral steroids to reduce inflammation and/or NSAIDs (non-steroidal anti-inflammatory drugs), both of which are very effective in reducing overall inflammation. Other conservative treatments include quality physical therapy. Physical therapy is used to assist in calming pain and inflammation, increasing mobility, and improving stability and strength. Physical therapists use many different modalities for spinal rehabilitation including cervical traction, manual manipulation, ultrasound, electric stimulation and dry needling. Learn more about therapy at the Virginia Therapy and Fitness Center and how their spine specialized Physical Therapists can help you.
When oral medications aren’t effective or symptoms are initially severe enough, a steroid injection can be effectively used to control inflammation. The steroid injection delivers targeted steroid medication directly to the affected site and can provide short-term to lasting relief. At the Virginia Spine Institute, the needle placement for steroid injections is guided by x-ray to ensure correct placement.
Surgery may be recommended if symptoms have not responded to conservative therapy or there is significant or dangerous neurological damage. Surgery is done to remove a portion or all of a damaged disc and free up any narrowed space for the nerves. If surgery is needed, your surgeon will discuss which surgery is most appropriate for you.
Dr. Schuler explains common causes of back and neck pain, including sciatica and pinched nerves. He discusses the complex network of nerves and how a pinched nerve in the spine can create pain in the extremities.
Pain Management Series, Part Three: New HorizonsViews 11007