Spondylosis is a general term for age-related wear and tear affecting the spine, often described as osteoarthritis of the spine. This condition can involve the discs, joints, and bones of the spinal column, leading to changes that may cause pain and stiffness. Magnetic Resonance Imaging (MRI) is a widely used diagnostic tool that helps evaluate these changes in the spine.
Why MRI is Used for Spondylosis
MRI is a preferred imaging method for evaluating spondylosis, offering significant advantages over X-rays or CT scans. Unlike X-rays, which primarily show bony structures, MRI provides highly detailed images of soft tissues, including intervertebral discs, ligaments, and nerves. This capability is particularly useful in spondylosis, where soft tissue changes often contribute to symptoms.
MRI’s ability to visualize soft tissues allows doctors to assess the extent of nerve compression or spinal cord involvement, which are common issues in spondylosis. For example, it can reveal if a disc herniation is pressing on a nerve root or if the spinal canal has narrowed, affecting the spinal cord. This detailed soft tissue contrast helps guide treatment decisions. While CT scans excel at showing bony details, MRI remains superior for detecting subtle soft tissue abnormalities and inflammation associated with spinal conditions.
What an MRI Shows in Spondylosis
An MRI scan reveals several specific changes in the spine associated with spondylosis. Disc degeneration is a common finding, appearing as desiccation, where discs lose water content and appear darker on MRI images. This can lead to a reduction in disc height and may result in disc bulging or herniation, where the disc material extends beyond its normal boundaries and can press on surrounding nerves or the spinal cord.
Another common finding is the presence of osteophytes, or bone spurs, which are bony outgrowths that form along the edges of the vertebrae as a reaction to disc degeneration and increased stress on the joints. These bone spurs can narrow the spaces within the spine, potentially affecting nerves. Spinal stenosis, which is a narrowing of the spinal canal or the neural foramina (the openings where nerve roots exit), is also visible on MRI. This narrowing can compress the spinal cord or nerve roots, leading to various symptoms.
Facet joint arthritis and hypertrophy, meaning enlargement of the facet joints, are also observed. These joints, located at the back of the vertebrae, can degenerate and become arthritic, contributing to pain and stiffness. Ligamentous hypertrophy, such as thickening of the ligamentum flavum, can also be detected. This ligament, found along the back of the spinal canal, can thicken and buckle, further narrowing the spinal canal and compressing neural structures. Additionally, MRI can show Modic changes, which are signal changes in the vertebral bone marrow adjacent to the discs, and may be associated with pain.
Preparing for and Undergoing an MRI
Before an MRI scan, you will receive specific instructions from your healthcare provider. It is important to remove all metal objects, including jewelry, watches, and any clothing with metal zippers or fasteners, as the MRI machine uses a powerful magnetic field. You must inform the staff about any implanted medical devices, such as pacemakers, cochlear implants, or certain metal implants, as these can be affected by the magnetic field. In some cases, a contrast dye may be injected to enhance the visibility of certain tissues or abnormalities. You may be asked to fast for a few hours if a contrast dye is used.
During the scan, you will lie still on a movable table that slides into the MRI machine, which is a large, enclosed tube. The machine produces loud knocking and clicking sounds as it takes images, so you will be provided with earplugs or headphones, often with music, to help with the noise. It is important to remain as still as possible throughout the procedure, which can last from 30 to 60 minutes, to ensure clear images.
If you experience claustrophobia, inform your doctor beforehand, as sedation options or the possibility of an “open” MRI machine may be available to help you feel more comfortable. An intercom system allows you to communicate with the technologist throughout the scan. After the scan, you can typically resume your normal activities unless you received sedation, in which case you will need someone to drive you home.
Understanding Your MRI Results
After your MRI scan, a radiologist, a medical doctor specializing in interpreting medical images, will analyze the images and prepare a report. This report will describe any findings related to spondylosis, such as disc degeneration, osteophytes, or spinal stenosis. It is important to understand that imaging findings do not always perfectly correlate with the severity of your symptoms. Many individuals, especially those over 40, show signs of spondylosis on MRI without experiencing significant pain or discomfort.
Your healthcare professional, often a neurosurgeon or orthopedic spine surgeon, will interpret the MRI results in the context of your specific symptoms, medical history, and a physical examination. This comprehensive evaluation helps determine if the changes seen on your MRI are contributing to your pain or other symptoms. The MRI results, combined with your clinical presentation, will then guide treatment decisions, which can range from conservative approaches like physical therapy and medication to, in some cases, surgical interventions if neurological symptoms are progressive or severe.