ANNULAR TEAR

An annular tear occurs due to the weakening of the cartilaginous outer layer of an intervertebral (spinal) disc, called the annulus fibrosus. A tear might not initially cause any pain or symptoms, but over time, regular daily activity can cause the tears to expand and then potentially compromise the integrity of the whole disc.

This condition of the spinal disc is one of many ways – along with collapsed, bulging, and herniated discs – that the all-important cushions between human vertebrae can break down. Being the frame on which the human skeleton hangs, the spine does a lot of work, and as humans age, even normal, regular activity can cause the discs to deteriorate. Annular tears and other related spinal disc concerns usually don’t manifest overnight, though athletes who participate in high-impact and high-stress sports can experience more acute spinal problems owing to the risks of their trade.

This article will break down all facets of annular tears: why they happen, what you might experience if you experience this affliction, and what surgical remedies are available. Like other spinal issues, annular tears can cause real pain in a part of the body where pain is felt more acutely. Fortunately, advances in modern spinal medicine provide patients with numerous options to treat this condition and set them back on the path to quick recovery.

WHAT IS AN ANNULAR TEAR?

In short, an annular tear is a condition that occurs when a crack develops within the fibrous ring (the outer layer) of the spinal disc.

When distinguishing between annular tears and other disc conditions, one must first understand the basic two-part structure of the disc.

The human spine consists of 33 vertebrae, but only 23 of them are cushioned by discs. There are six discs in the cervical (neck) region, 12 in the thoracic (upper-to-middle back) region, and five in the lumbar (lower back) region. 

The bottom two portions of the spine, the sacrum and coccyx (tailbone), do not feature discs. In the more flexible upper two-thirds of the spine (cervical, thoracic, lumbar), spinal discs provide the flexibility and shock absorption necessary for the range of body movement.

Spinal discs can be thought of almost as flat jelly donuts. Each “donut” has two parts. The gelatinous nucleus pulposus makes up the inner portion of the ring and is the more flexible of the two parts. The annulus fibrosus, as its name implies, forms a fibrous ring around the nucleus pulposus that allows the gelatin-like inner layer to serve as a stretchy protective layer between each vertebra. Without the annulus fibrosus, the pressures exerted by the spine would cause the “jelly” to stick out of each intervertebral space, much like a herniated disc.

An annular tear, therefore, occurs when a crack develops within the fibrous ring layer of the spinal disc. Owing to its purpose in the spinal anatomy, the annulus fibrosus is the toughest part of the intervertebral disc. But regular wear and tear, combined with additional stresses that come from repetitive movement or athletic activity, can cause this firmer feature of the disc to weaken.

These tears take three distinct shapes:

• Radial Tears are the most common kind of annular tear. They begin from within the center of the ring, where the nucleus meets the annulus. These tears usually stem from normal wear and tear. As vertebrae push down on discs over time, the nucleus is continually pressed up against the ring that contains it, a condition that will sometimes result in the emergence of a tear.

• Concentric Tears take the shape of the annulus itself, the form of a ring. These can occur due to stress brought about by a sudden and severe twisting of the spine.

• Peripheral Tears start at the outer layer of the disc, the part that is visible to a spinal surgeon when they perform spinal surgery. This type typically happens as a result of a direct blow to the spine, such as a hard fall or a particularly aggressive contact during athletic competition.

One annular tear on its own may not amount to much, and it’s possible that a small tear can develop without leading to other complications. But because the annulus fibrosus’s primary task is to envelop the nucleus pulposus, a small crack can cause the nucleus to penetrate the annulus (a bulging disc) and even precipitate a more serious herniated disc, when the exterior of the annulus fails to contain the nucleus altogether.

This is not to say that every single annular tear will cause a snowball effect that leads to complete disc failure – far from it. However, spinal discs naturally decrease in efficacy as human beings age, meaning that it’s important to address potential sources of further injury before they emerge.

WHAT ARE THE SYMPTOMS OF AN ANNULAR TEAR?

So, when might you start to detect an annular tear? Usually, it won’t be at the moment of the tear itself. It’s possible to go on living for quite some time without experiencing any symptoms at all, especially with small tears. Moreover, spinal discs are capable of healing themselves, and a small tear could simply come and go. Of the three types of tears, radial tears are the ones most likely not to provoke any symptoms, as the core of the spinal disc has fewer pain receptors than the outer portions.

Those who experience a symptomatic case of spinal tears will most likely experience pain directly at the site of the tear itself. This pain will be more pronounced in instances where the spine is in an active or weight-bearing position, which includes sitting with upright posture.

Nerve issues might come into play should the tear expand or the disc weaken as a whole. Nerve-related symptoms include radiating pain beyond the site of the tear itself, muscle weakness, tingling, numbness, and/or the “hitting the funny bone” feeling.

WHEN TO SEE A DOCTOR FOR AN ANNULAR TEAR

It would be prudent to reach out to your spinal specialist once any of those nerve-related symptoms appear. The spine exists not just for skeletal structure but also protection, as the spine shields the central nervous system that dictates our ability to move around. Presentation of nerve symptoms is a signal that what may have begun as a single tear in a disc now threatens to affect the nervous system.

Along with the kind of pain, the level of the pain matters for patients assessing whether a doctor visit is necessary. The annulus fibrosus contains many more pain receptors than other parts of the spinal disc, so a tear of some size can cause severe pain, which should, of course, be answered with a quick call to the doctor.

This doesn’t mean, though, that one must wait until things look dire to consult with a spinal specialist. The first flush of back pain shouldn’t be a cause of terror either, as small tears can heal themselves, especially if assisted with gentle stretching, rest, and applying heat to the affected area. Avoiding strenuous activity, athletic or otherwise, can also help back pain dissipate.

But if your back pain lingers despite the standard home remedies, you should make an appointment as soon as you can with a spinal specialist. This holds particularly true for those who have a genetic predisposition to spinal problems.

WHAT DOES AN ANNULAR TEAR FEEL LIKE?

Those who experience a symptomatic case of spinal tears will most likely experience pain directly at the site of the tear itself. This pain will be more pronounced in instances where the spine is in an active or weight-bearing position, which includes sitting with upright posture.

DIAGNOSIS

When you meet with your spinal specialist, they will likely want to first get a clear assessment of your pain. This might include asking you to perform some simple tasks to get a sense of how much the pain flares up depending on the position of your spine.

Your doctor will also want to know of any recent accidents or incidents that could plausibly lead to a disc-related concern, such as traumas, falls, or any unusual movements (such as the way some of us will unexpectedly “throw our back out” with a random movement).

Though the doctor will likely suggest some of the traditional, easy at-home remedies (such as rest and applied heat), if they deem a test necessary, they will order a scan to detect the tear. Options include a CT scan, an MRI, or an X-ray. Some of those scans, namely the CT or X-rays, could be done in accompaniment with a discogram, where contrast fluid is injected into the affected disc to give the doctor a clear picture of the condition of the whole disc. However, patients with severe pain may opt out of any contrast-based scan to avoid further pain. Your spinal specialist will be able to identify which scan is best suited for your specific case.

TREATMENT POSSIBILITIES

Barring cases of extreme pain, such as those caused by an acute tear stemming from a violent trauma, your spinal specialist will likely recommend a cautious approach to see if the annular tear can heal naturally. At-home rest and remedies, along with anti-inflammatory medications available over the counter, can and do resolve small tears routinely.

So long as the tear does not expand or cause other issues with the afflicted disc, surgery should not be necessary. Maintaining good spinal health and getting rest should, over time, result in a healed disc. Additional regimens such as physical therapy or spinal traction might be recommended by your doctor.

Patients have several surgical options, however, if routine care and rest do not heal the tear or it balloons into a bigger issue. Spinal surgery can seem daunting and frightening, but thanks to advances in what is called Minimally Invasive Spine Surgery (MISS), spinal patients now have more options than ever before to address their needs surgically in a way that reduces the number of incisions needed to perform a procedure, which, in turn, enables a faster post-operative recovery time. There are even spinal procedures performed with robotic assistance that give surgeons a greater degree of precision.

Depending on the nature of your specific tear, your spinal specialist has a few surgical interventions they could perform:

• Endoscopic Discectomy: Endoscopic procedures are so named because they are performed with the use of an endoscope, a flexible tube with a light and a camera affixed to its end so that doctors can see the area on which they will operate. This minimally invasive strategy removes the need to open up a patient with a large incision and, in turn, reduces the size of the incisions needed for the procedure. When a discectomy (removal of disc) is done with an endoscope to treat an annular tear, the surgeon will use an endoscope to remove the damaged portion of a disc. Though the suffix “-ectomy” may suggest a complete excision, in some cases an annular tear may not require such a drastic intervention.
  

• Total Disc Replacement: However, the tear may be significant enough to warrant the complete replacement of the disc, especially if the overall condition of the disc is greatly compromised. With total disc replacement (TDR), your spinal surgeon will remove the disc and then insert a disc made of artificial materials (such as ultra-high molecular weight polyethylene or polycarbonate urethane) that will serve the same purpose that your native (natural) disc once did. TDR is an area of great interest and research, with new technologies promising artificial discs that allow patients to return to pre-disc injury levels of movement.
  

• Spinal Fusion: An alternative to TDR, spinal fusion occurs when the surgeon fuses the two adjacent vertebrae together, forming one fused bone, rather than attempting to replace the now-lost disc. Though spinal surgeons still do perform fusions, the efficacy of the procedure is regularly debated, given that the fusion provides less flexibility than what is offered by a disc replacement, which creates conditions that more naturally mirror normal spinal movement.

It should be stressed that the surgical options above, in the case of a tear, will only factor in for the most extreme of cases. Much can be done with basic at-home treatments to solve annular tears.

If you’re worried that your back pain may be the sign of an annular tear and that your at-home routine is not doing enough to help the pain go away, call your spinal professional.

CAUSES OF ANNULAR TEARS

Genetics is one factor that can contribute to the development of annular tears. Those predisposed by birth to spinal trouble already know to take special care of their spinal health through regular stretching and low-risk exercise, and by doing so, they’ll reduce their risk of developing annular tears.

As with most spinal maladies, however, the likeliest culprit for an annular tear is a familiar foe: the forward march of time. Human lifespan has improved considerably in recent centuries, but our bodies naturally diminish over time, and given the amount of work that our spines do in keeping our bodies upright and bearing our body weight in that position, it’s only a matter of time before the component parts of our spines grow weak and brittle. Even the most healthy, athletic, and limber people can experience some kind of spinal affliction.

Of course, there are things that can provoke or contribute to a tear outside of the normal aging process. These include:

• Sitting for long periods (i.e., those with desk jobs)

• Jobs that require repetitive motion, especially if one of those motions involves bending over

• Poor spinal maintenance (i.e., irregular or rare exercise and stretching)

• Sudden sharp spinal movements or twists

• Playing certain high-risk sports like American football

• Carrying excess body weight relative to one’s frame.

One can minimize their risk of developing annular tears much in the same way that they can maintain their overall spinal health: consistently hold good posture while sitting and standing, adopt a regular exercise regimen, take breaks if expecting to sit for long periods, and so on.