What is a disc herniation?
A disc herniation occurs when the inner gel-like center (nucleus pulposus) of an intervertebral disc breaches the surrounding outer fibrous wall (anulus fibrosus) of the intervertebral disc. Disc herniations are often called “a ruptured or slipped disc,” referring to when the nucleus pulposus ruptures through a tear in the anulus fibrosus. If the gel-like center remains within the anulus wall, it creates an outpouching of the intervertebral disc, this is called a disc protrusion or a “bulging disc.” When there is a disorder of the disc, the displaced disc material can impinge on neural structures.
Side (left MRI) and cross-section view (top right illustration and lower right MRI) of a disc herniation and a compressed nerve root
The left is an MRI side view of a compressed nerve root resulting from a disc herniation in the lumbar region. On the lower right is an MRI cross-section view of the pathology. The top right is an illustration of the cross-section.
WHAT ARE THE SYMPTOMS OF A DISC HERNIATION?
Symptoms vary greatly depending on the location and degree of the herniation, the neural structures that are being affected and your own response to pain. Intervertebral disc herniations most commonly occur as pain that starts in your low back area and radiates down one or both legs. When this type of low back pain travels to your feet the pain pattern is called sciatica.
The pain may feel like an electric shock that is intense, often worsened by bending, lifting, twisting, sneezing, or certain positions such as sitting. Often the pain persist even while standing or walking. Sometimes the pain is accompanied by numbness or weakness. In severe cases of lumbar disc herniations, you may experience foot drop (your foot flops when you walk) and/or loss of bladder or bowel control. Disc herniations in cervical spine can cause similar radiating pains from the neck to the arm or hand. If you experience rapid onset leg weakness or difficulty controlling bladder or bowel function, you should seek medical help immediately at the emergency room.
WHAT ARE THE CAUSES OF DISC HERNIATION?
Discs herniations can occur spontaneously or can be caused by injury due to improper axial loading (lifting). Genetics, smoking, and a number of occupational and recreational activities may lead to early disc degeneration. Aging also plays an important role. As you age the Intervertebral discs become dehydrated and harder. This can cause the tough fibrous disc wall to weaken, making it susceptible to tears. The gel-like nucleus may bulge or rupture through a tear in the disc wall, resulting in a disc herniation.
HOW IS A DIAGNOSIS MADE?
A health care provider will take a history of your symptoms and perform a physical exam. The history and physical exam will help determine the source of the pain and test for muscle weakness or numbness. If the findings from the history and physical are consistent and suggest a disc herniation, a magnetic resonance imaging (MRI) study is obtained to confirm the diagnosis. In certain circumstances your doctor may order additional studies such as: an X-rays, computer topography (CT) scan, or electromyography (EMG) study.
WHAT TREATMENTS ARE AVAILABLE:
The first line of treatment for a disc herniation is conservative, non-surgical therapy, which includes but is not limited to; pain management with medication, physical therapy, epidural steroid injections (ESI) and nerve blocks or alternative therapies. Non-surgical therapy treatments will result in significant improvement and return to normal activity in roughly 80% of people in about 6 weeks. If you don’t respond to conservative treatment, your doctor may recommend surgery. Surgery may also be recommended if you have signs of nerve damage, such as weakness or loss of feeling or problems with your bladder function.
WHAT SURGICAL TREATMENTS ARE AVAILABLE?
Surgical treatment of a herniated disc will vary due to multiple contributing factors that your surgeon considers before making a surgical plan. Some of these factors include but are not limited to your symptoms, the location and size of the herniation, your overall health, as well as your spine health and spinal alignment. Surgery for disc herniations can be performed in the cervical, thoracic or lumbar spine. Most disc herniation surgeries only require a decompression of the compressed neural structures, however some require a decompression and fusion procedure. These surgeries can be performed using an open traditional surgical technique, a minimally invasive technique or full-endoscopic surgical technique.