Lumbar Stenosis

The lumbar spine consists of five vertebrae (L1-5). The most common site of stenosis is L4-5 in 91% of cases. The spinal cord is housed in the vertebral column, and the nerve root is the segment of the spinal nerve that emerges from the spinal cord to innervate parts of the body, including the limbs. Facet joints are small stabilizing joints that connect the vertebrae and permit bending and twisting.

Lumbar spinal stenosis is the narrowing of the spinal canal in the lower back. This narrowing puts pressure on the spinal cord and the nerves that travel through the spine to the legs, which can lead to various symptoms.

This condition can cause pain, numbness, tingling, muscle fatigue, and weakness in the legs and lower back. When the nerve roots in the lower back are compressed, it can result in sciatica pain that radiates into the buttocks and legs.

The most common cause is age-related degenerative changes in the spine.

Age-Related Degenerative Changes: Lumbar spinal stenosis commonly occurs as a result of the aging process. Over time, the spinal structures deteriorate, leading to spinal stenosis.

• Osteoarthritis: The breakdown of cartilage in the joints of the spine (facet joints) can result in inflammation and bone spurs, narrowing the spinal canal and compressing the nerves.
• Degenerative Disc Disease: The discs between the vertebrae act as shock absorbers. As people age, these discs can lose water content, become thinner, and collapse, reducing space in the spinal canal. Bulging or herniated discs may further contribute to narrowing.
• Thickening of Ligaments: The ligaments that support the spine can thicken over time, bulging into the spinal canal and narrowing the space for the spinal cord and nerves.

Herniated Discs: A herniated disc occurs when the soft center of a spinal disc bulges through a tear in the outer layer. This can put pressure on the spinal cord and nerve roots, contributing to stenosis.

Degenerative Spondylolisthesis: This condition involves the slipping of one vertebra over another, often due to a stress fracture or degenerative changes. This narrowing of the canal can compress the spinal cord, causing pain and instability and accelerating the formation of arthritic bone spurs.

Trauma: Trauma to the spine, such as from a car accident or fall, can cause spinal fractures or dislocations that narrow the canal and compress the nerve roots.

The symptoms of lumbar spinal stenosis can vary depending on the severity of the condition and the specific nerves affected. Common symptoms include:

• Pain, numbness, tingling, and/or weakness in the legs, particularly when standing or walking.
• Difficulty standing, sitting, and walking for long periods.
• Low back pain, buttocks, legs, and feet discomfort.
• Cramping, fatigue, and weakness in the legs.
• Difficulty maintaining balance.
• Sensory loss.
• In severe cases, loss of bladder or bowel control.

Symptoms often improve when sitting or bending forward, which opens up space in the spinal canal and alleviates pressure on the nerves.

Spine surgeon Dr. Mathew Cyriac will review your medical history and inquire about your symptoms and any trauma or injuries. The physical exam will focus on detecting signs of spinal cord compression, such as muscle weakness, abnormal reflexes, or changes in sensation. Imaging tests such as an X-ray will be ordered to view changes in the height of the disc space, while an MRI provides a detailed image of the soft tissues in the spine, showing the extent of spinal cord compression and narrowing. In some cases, a CT scan with dye may be ordered to better visualize the spinal cord and nerve roots.