Your spine is made up of bones called vertebrae. Each bone has two parts: the body, which is flat and roughly round, and the vertebral arch, which is the spiny-looking part on the back. When you look at a vertebra from the top (Figure 1, left), you can see that there's a space between the vertebral body and the vertebral arch. In your spine, these round openings in the vertebrae line up, forming a protective tunnel around the spinal cord (Figure 1, right). This bony tunnel is called the spinal canal. At each vertebral level, small openings in the bone allow nerves, vessels, and supporting ligaments to exit the spinal canal. These small openings are called foramina (the singular form of foramina is foramen, from the Latin word forare, meaning "to bore or pierce"). Spinal stenosis is a painful, sometimes disabling condition. It's typically caused by degenerative changes associated with osteoarthritis, such as overgrowth of bone and soft tissue. The space within the canal narrows, putting pressure on the spinal cord. In foraminal spinal stenosis, a variant of the condition, the foramina (fuh-RAM-in-uh) become narrowed, impinging on nerves that pass through these openings.
What is spinal stenosis?
The spinal canal contains the spinal cord, an amazing two-lane superhighway carrying signals that control movement and sensation. One lane conducts motor impulses from the brain to your body. This pathway governs all voluntary movement-everything from driving to the sports stadium to munching a hot dog and leaping to your feet when your team scores.
The other lane sends sensory information from your body to your brain. Signals arriving from this lane tell your brain all too clearly that-Argh!-that trek from the parking lot to the stadium was painful, and your cushy box seat feels pretty good right now.
Normally, signals flow freely in both directions. But what if space inside the tunnel gets tight, narrowing the roadway? That’s what happens in patients with spinal stenosis.
Acquired spinal stenosis
Spinal stenosis that develops over time or as a result of injury is known as acquired spinal stenosis. It’s also associated with certain endocrine system and metabolic disorders, and with certain autoimmune disease. Even infectious disease can sometimes lead to spinal stenosis. Any spinal cord dysfunction associated with acquired spinal stenosis is called myelopathy.
Congenital spinal stenosis
People born with a narrow spinal canal have a form of the disease called congenital spinal stenosis.
What are the symptoms of spinal stenosis?
When the condition affects the lumbar spine, it can cause aching pain in the buttocks, thighs, or knees, a sensation of warmth in the legs, sciatic pain, or back pain. Patients report having trouble standing for long periods. Spinal stenosis of the cervical spine can cause pain, weakness, or numbness in the arms or hands. Most patients have pain on both sides of the body.
What causes spinal stenosis?
Degenerative disc disease
Calcification of spinal ligaments
Aging can calcify the ligaments that pass through the spinal foramina. They become hardened and thickened, a condition called hypertrophy (hy-PER-troe-fee). The thickened ligment can compress the spinal cord.
Bone spurs, which doctors call osteophytes (OSS-tee-oh-fytes) can form within the spinal canal, impinging on the spinal cord.
Spondylolisthesis (spahn-dih-low-LISS-thuh-siss) occurs when a vertebra shifts forward or backward, out of alignment with the vertebra above it. A misaligned vertebra can crowd the spinal cord.
Facet joint syndrome
Facet (fuh-SETT) joints can become arthritic, constricting the neural foramina.
How common is spinal stenosis?
How is spinal stenosis diagnosed?
How is spinal stenosis treated?
An NSAID such as indomethacin (Indocin) can reduce inflammation within the spinal canal. Anticonvulsant and antidepressant medications, such as gabapentin (Neurontin) and pregabalin (Lyrica), can interrupt the transmission of pain signals from the spinal cord to the brain.
To relieve pain caused by spinal cord compression, the doctor can inject an anesthetic agent and a long-acting steroid medication into the epidural space (the space between the membranes protecting the spinal cord and the walls of the spinal canal).
Performing specific exercises can help you maintain spinal motion, strengthen your back and abdominal muscles, and build endurance. These efforts stabilize the spine. A licensed therapist can also apply pain-relief interventions, such as electrical stimulation, massage, ultrasound therapy, and heat/cold therapy.
Surgical treatment of spinal stenosis is aimed at relieving pressure on the spinal cord and keeping the disease from progressing. Your surgeon’s operative approach depends on which portion of your spinal cord is compressed.
Surgery typically involves an open procedure known as a laminectomy. Although that approach often works well, half of patients end up with lingering back pain and stiffness. An alternative approach perfected by Inspired Spine is called oblique lateral lumbar interbody fusion (OLLIF). Using this minimally invasive keyhole procedure, patients recover quickly and many return to life as they knew it before back pain began to steal the show.
Call Inspired Spine today at 727-MY-SPINE to speak with one of our Patient Care Coordinators.