Foraminal narrowing, or foraminal stenosis, is a condition of the spine that can cause pain and other symptoms resulting from spinal nerve compression. At every level of the spine, a pair of nerve roots exit the spinal cord through small openings called foramina (singular: foramen). Narrowing, or stenosis, occurs when the space available for the nerve roots to pass is reduced. While narrowing of the foraminal canals does not necessarily produce symptoms, if a nerve root is irritated or compressed, it can cause pain that radiates along the length of the nerve, as well as tingling, numbness, or weakness within the muscle group innervated by the affected nerve.
Causes of Foraminal Narrowing
Most cases of foraminal stenosis are related to gradual anatomical deterioration that is associated with the aging process. The vertebrae, intervertebral discs, and other spinal components break down after years of wear and tear, especially within the cervical (neck) and lumbar (lower back) regions of the spine. Most of the time, this anatomical degeneration affects one side of a vertebral segment, producing unilateral foraminal narrowing. Sometimes, degeneration affects both sides of a vertebral segment, and this is known as bilateral foraminal stenosis. Conditions that can produce stenosis within the foraminal canals include:
- Degenerative disc disease – deterioration of an intervertebral disc can lower the disc’s height, reducing space available for nerve roots to pass.
- Herniated disc – extruded disc nucleus material through a tear in the disc’s outer wall can leak into the foraminal opening.
- Bulging disc – a portion of the outer disc wall can protrude into foraminal space.
- Bone spurs – osteophytes resulting from arthritis of the spine can grow along the edges of the foramina, constricting available space.
- Spondylolisthesis – slippage of one vertebra over another can reduce foraminal space significantly.
- Spinal injury – a fracture or compression injury can displace the vertebrae, thereby reducing space available for nerve roots to exit the spinal cord.
Treatment for Foraminal Narrowing
An attempt to manage symptoms associated with foraminal narrowing typically begins with pain medication, exercise, and/or corticosteroid injections. If symptoms persist after several weeks of conservative treatment, contact Laser Spine Institute to determine whether a minimally invasive, outpatient procedure known as a foraminotomy may be able to help you rediscover your life without back or neck pain.