Spinal stenosis is a condition that causes a narrowing of the spinal canal, which can compress the spinal nerves, resulting in pain. When this condition occurs in the lower back it is referred to as lumbar stenosis.
A narrowing of the spinal canal typically doesn’t cause symptoms unless it progresses to a point where it compresses the spinal cord, spinal nerves, or the cauda equina, which is a dense bundle of nerve roots that begins where the spinal cord ends in the upper lumbar region. When compression happens, intermittent or chronic pain, numbness, or weakness may arise in the low back, buttocks, and legs. Symptoms are usually mild or absent while sitting or sleeping. While walking, symptoms generally increase and a cramping sensation with a tired or heavy feeling in the low back, buttocks, or upper thighs may occur.
Lumbar stenosis is most frequently caused by degenerative changes (osteoarthritis) in the lower back. After years of normal wear and tear, cushioning between bones in the spine may break down, allowing bones to wear against each other. At these sites, the body produces growths called bone spurs that may narrow the spinal canal, causing pressure on the spinal nerves, or cauda equina. Occasionally, large disc herniations and spinal tumors can narrow the spinal canal enough to cause compression.
Lumbar stenosis may or may not require treatment depending on whether symptoms include pain or disability. Non surgical treatments may include modifying activities to reduce stress on the spine, physical therapy, medications or injections to reduce pain and inflammation, or wearing a brace. In severe cases or those that are progressively worsening, surgery may be performed to correct the condition.