You may think a bulging disc is the same as a herniated disc, but there is a difference. With a herniated disc, a crack occurs in the outer layer of the disc, called the annulus. The crack usually affects a small part of the disc, and it allows the soft inner material of the nucleus pulposus to rupture out of the disc. A bulging disc is different because the disc simply bulges outside the space it normally occupies between your vertebrae, but it doesn't rupture. A bulging disc affects a much larger part of the disc than a herniated disc. While it is more common to have a bulging disc than a herniated disc, a herniated disc is more likely to be painful. It's possible for you to have a bulging disc without feeling any pain at all.
A bulging disc is usually considered a normal part of aging. Some discs most likely begin to bulge as a part of both the aging process and the degeneration process of the intervertebral disc. A bulging disc is not necessarily a sign that anything serious is happening to your spine.
A bulging disc only becomes serious when it bulges enough to cause narrowing of your spinal canal. If there are bone spurs present on the facet joints behind the bulging disc, the combination may cause narrowing of your spinal canal in that area. This is sometimes referred to as segmental spinal stenosis. View animation of bulging disc.
Injury to your intervertebral disc, and overuse or misuse of the disc such as might be experienced by an athlete or a person with a very physical job, can weaken the disc and make it more prone to problems. Smoking tobacco can also cause your disc to weaken and deteriorate.
Bulging discs are fairly common in both young adults and older people. They are not cause for panic. As the disc bulges out between the vertebrae and presses on a nerve, you will experience symptoms in whatever part of your body the affected nerve serves. The symptoms of a bulging disc include pain, numbness, and muscle weakness. Depending on which nerves are affected, a herniated disc can include pain that feels like it is coming from another part of your body, such as your heart, abdomen, or kidneys.
Bulging discs sometimes press against your spinal cord. When this happens, symptoms may include:
- Bulging disc in your thoracic spine:
- Muscle weakness, numbness, or tingling in one or both legs
- Increased reflexes in one or both legs that can cause spasticity
- Changes in bladder or bowel function
- Paralysis from the waist down
- Bulging disc in your cervical spine:
- Pain moving your neck
- Deep pain near or over your shoulder blade
- Radiating pain in your upper arm, forearm, and possibly your fingers
Pain from a bulging disc may start slowly and get worse over time or during certain activities. The symptoms of herniated disc often get better within a few weeks or months.
Diagnosing a bulging disc begins with a complete history of the problem and a physical exam . Your doctor may ask whether you are aware when you have to urinate or have a bowel movement. If there is a problem, it could indicate that a bulging disc in your thoracic spine is pushing against your spinal cord. Your doctor may also want to perform certain diagnostic tests including an X-ray, MRI, or CT scan.
Your doctor may suggest taking X-rays of your spine. Although an X-ray can't show a bulging disc, it can give your doctor an idea of how much wear and tear is present in your spine.
The most common test to diagnose a bulging disc is the MRI scan. This test is painless and very accurate. It is usually the preferred test to do (after X-rays) if a bulging disc is suspected.
Sometimes, the X-ray and MRI do not tell the whole story. Other tests may be suggested. A myelogram, usually combined with a CT scan, may be necessary to give as much information as possible.
A bulging disc does not necessarily mean that you will need to undergo surgery. The treatment of a bulging disc depends on your symptoms. Most patients with a bulging disc do not need surgery. Your symptoms can usually be managed with conservative treatment such as watching and waiting to see whether your symptoms go away, pain medications, and physical therapy. Many patients who initially have problems due to a bulging disc find their symptoms completely resolve over several weeks or months.
If your symptoms are getting steadily worse, your doctor may be more likely to suggest surgery.
When surgery is needed to treat a bulging disc, your doctor will likely perform a laminotomy and discectomy. The term laminotomy means "make an opening in the lamina", and the term discectomy means "remove the disc." The purpose of taking out a bulging disc is to decompress your spinal cord or spinal nerves. However, nerve problems have occurred with this traditional method of decompression, which has led many doctors to discontinue this form of surgery for herniated disc.
If the bulging disc is in your thoracic spine and surgery is needed, your doctor may perform transthoracic decompression, which is a way to decompress your spinal cord or spinal nerves by removing a small amount of the vertebral body and problem disc through a small opening in the side of your chest. If a large section of vertebra has to be taken out, you may also need spinal fusion.
A bulging disc in your thoracic spine may also be treated surgically with a costotransversectomy, in which a section of the transverse process (the small bone on the side of the vertebra) is taken off, which helps the doctor to see and then treat the injured disc through an incision through the back of your spine.
Video Assisted Thoracoscopy Surgery (VATS) is a new way to perform thoracic surgery in which the doctor can see and treat the bulging disc using a small TV camera that is passed through your chest cavity. Because the incisions are small, most patients have an easier time recovering from the VATS procedure.
If surgery on a bulging disc requires removal of a large section of bone and disc material, the section of spine may become loose or unstable. When this happens it may be necessary to fuse the bones right above and below the unstable section. Bone graft material is used to get the unstable bones to grow together. Rods, plates, and screws are commonly used to hold the bones in place so the bone graft heals.