What is Annular Disc Tear?
An annular fissure, or tear, is when one or more layers of the annulus fibrosus, a part of your spine, is damaged. Most of the time, people with annular fissures don’t feel any symptoms. However, some may experience pain.
Usually, annular fissures that cause pain but don’t involve a herniated disc are treated with anti-inflammatory drugs and low-impact physical therapy. Chronic pain from annular fissures can be caused by the growth of new tissue or nerve endings, often seen near the dorsal root ganglion, a cluster of nerve cells in the spine.
Moreover, an annular fissure can permit the inner part of a disc, called the nucleus pulposus, to seep out. This can lead to a disc herniation, which may press against nearby nerves, leading to further issues.
What Causes Annular Disc Tear?
The annulus fibrosus is a strong band made up of type I collagen that wraps around the nucleus pulposus. These two components form the disc that sits between the bones of the spine known as vertebrae. The annulus fibrosus attaches the top of one vertebra to the bottom of the one above it. It does this in a unique way, with the different layers running in opposite directions, which adds to its strength.
Where the annulus fibrosus meets the nucleus pulposus in the center, the two structures blend together. However, the back portion of the annulus fibrosus has more vertically-arranged fibers, which makes it relatively less strong. This detail about the structure of the annulus fibrosus helps explain why most cracks or tears (known as annular fissures) tend to appear at the back or back-side parts of it.
Risk Factors and Frequency for Annular Disc Tear
Annular tears often show up in imaging tests for other medical reasons, even in people who don’t show any symptoms. How often these tears occur in adults can greatly vary. The estimates range from just a few percent to more than 50%, depending on the criteria and type of imaging used to spot these annular tears.
Signs and Symptoms of Annular Disc Tear
An annular fissure or annular tear refers to a type of spinal condition. These are often not noticed due to a lack of symptoms and are usually found during imaging scans for other reasons. However, when symptoms do occur, they typically fall into two categories. Some people experience localized pain due to the tear itself, while others have radicular symptoms caused by irritation of the nerve root. The pain can either come suddenly, in the case of an acute tear, or develop gradually over time when the annular fissure slowly worsens.
- Pain localized deep in the spine, which worsens with movements that can stress or irritate the tear. There are no nerve-related symptoms, and a physical exam might not reveal any issues in such cases.
- The annular tear might irritate a nerve and cause radiculopathy. In severe cases, disc material can push out, irritating or compressing surrounding nerves or the spinal cord. This nerve irritation can result in radicular symptoms, which include pain, tingling or numbness, and even muscle weakness, depending on the level of nerve irritation or damage.
Testing for Annular Disc Tear
An ‘annular fissure’ is a condition that affects the spine. This term describes a tear that can occur in different directions and in some or all layers of the annulus fibrosus, a hard and elastic part of the disc in our spinal column.
If we use an imaging technique called magnetic resonance imaging (MRI), the area of the tear seems brighter on the images. This is because the spot of the tear holds more water compared to the normal, healthy annulus fibrosus, which normally appears darker.
When there is a condition called ‘disc herniation’ – where the soft material of the spinal disc pushes out through a tear in the tougher outer casing – this means that the annulus fibrosus isn’t working correctly. Therefore, we can assume that there is a tear or fissure, even if we can’t see it directly on the images.
In some cases when a patient can’t have an MRI, a different type of scan can be carried out called a computed tomogram (CT) myelogram. This can show if the herniated spinal disc is putting pressure on the nerves or spinal cord. However, this CT scan can’t pick up the swelling of a tear or fissure in the annulus fibrosus as clearly as an MRI. So it’s not as reliable for identifying this specific problem.
Treatment Options for Annular Disc Tear
An annular tear in the spine can either cause symptoms or not. Tears without symptoms are often discovered by accident and may heal on their own. Tears with symptoms can be treated with anti-inflammatory medications and physical therapy. In chronic cases, surgery may be recommended. If a tear is accompanied by a disc protrusion or herniation, the patient is treated for the disc issue, not the tear. Surgery may be considered if other treatments are not effective. However, there is no clear evidence that closing up the tear makes a significant difference in long-term outcomes.
What else can Annular Disc Tear be?
- Diverticulitis
- Infections in the protective layers around the spine
- Shingles
- Back pain caused by mechanical issues
- Kidney stones
- Bone infection in the context of emergency medicine
- Pelvic fracture treated in emergency medicine
- Inflammatory disease affecting the female reproductive organs
- Rheumatoid arthritis, a type of joint inflammation
- Sickle cell anemia, a genetic blood disorder
What to expect with Annular Disc Tear
Generally, mechanical back pain is mild and tends to go away on its own. Even with conditions like a slipped disc in the lower back without any nerve damage, the outlook is often good in the mid and long term with non-surgical treatments.
However, if the patient is experiencing nerve-related issues, it could be beneficial to consider surgery as an option.
Possible Complications When Diagnosed with Annular Disc Tear
A bulging spinal disc might lead to a variety of health problems. Here are some of them:
- Cauda equina syndrome (nerves at the lower end of the spinal cord are compressed)
- Conus medullaris syndrome (swelling or damage to the lower tip of the spinal cord)
- Deep vein thrombosis, bedsore, atelectasis (lung tissue collapse), and urinary infection – symptoms that can occur when a patient is unable to leave the bed because of paralysis
- Motor neurological deficits (problems with muscle control or movement)
- Sensory neurological deficits (difficulty with sensation)
Preventing Annular Disc Tear
Patients are advised to:
* Take their prescribed medication as directed
* Limit their physical activities as recommended
* Steer clear of activities that involve extreme spine movements.
