Annulus Tear or Sprain
Annular Tear Definition:
An annular tear is a hole or rip somewhere in the interwoven layers of the annulus fibrosus, the tough ligament that forms the exterior capsule of an intervertebral disc.
Intervertebral discs are pressurized cushions found between each bone of the spine. These discs act as shock absorbers and allow the spine to bend in several directions. Each one consists of the annulus fibrosus and, inside the capsule, the nucleus polposus, which consists of a soft, gel-like substance. The nucleus and the inner layers of the annulus have no blood supply or nerve fibers. It is only the outer layers of the annulus that are supplied with many nerve fibers and so are sensitive to pain. Annular tears, therefore, are often asymptomatic, which means that their existence does not necessarily produce any symptoms.
The peripheral layer of the annulus consists of the outer layers. Damage to this layer is usually caused by an injury, and can lead to disc degeneration. The concentric, or central, layer is found between the outer and inner layers. Tears to this layer are also usually as a result of trauma. The inner, radial, layer begins at the center of the disc and extends to the peripheral layer.
Annular tears can happen in any layer, and symptoms, if present, can therefore be felt anywhere along the spine and sometimes in the limbs as well.
Annular Tear Causes:
The normal aging process is commonly responsible for annular tears. With time and usage the annulus becomes thinner, losing elasticity and becoming vulnerable to damage. Small holes gradually get larger and, if large enough, the material of the nucleus can start to leak out of the capsule.
Contact sports, with the vigorous bending, twisting and collisions that take place, also often lead to annular tears. Any strenuous activity or occupation involving heavy lifting or lots of bending may cause tiny injuries that may, over time, escalate into a larger tear.
Another common cause for such injury is being overweight. As the spine supports most of the weight of the body, excessive load can compress the discs and increase the risk of tears appearing in the annulus.
Annular Tear Symptoms:
When enzymes contained in the gel-like substance of the nucleus leak out through the annulus and reach the peripheral layer with its many nerve endings, there is a strong inflammatory chemical reaction. This is when pain begins to be felt as a result of having a tear.
If the disc is herniated (the disc is bulging out between the vertebrae, or has actually ruptured), the pain may be experienced as a sharp stabbing sensation, tingling similar to pins and needles, numbness of the skin, or weakness in the limbs, depending on the location of the damaged disc. Pain is typically felt in the back, but can also be felt in one or both legs. There may be some swelling due to inflammation.
Increasing the pressure on the disc will make the pain worse, as will sitting, coughing, sneezing, bending or lifting. Standing will make the pain better.
Annular Tear Diagnosis:
Your medical history will be taken by your health care provider, and a physical examination performed. You will be asked questions relating to the onset and severity of your symptoms. An x-ray may be taken to rule out any fracture of the bones.
The best test for diagnosing an annular tear is a CT (computed tomography) scan. Dye can be injected into the nucleus of the disc, which then shows up clearly on the scan. An MRI scan is not as good at showing a tear, but may be useful in identifying the location of the damaged disc. A nerve conduction study may be performed.
Annular tears are classified according to severity and extent, ranging from 0 for a perfectly normal disc, to 6 for the worst tear and leakage of the nucleus.
Annular Tear Treatment:
Most tears heal by themselves, with some self-treatment, and never need surgery. Scar tissue forms in the outer layers of the annulus, forming a plug through which the nucleus material cannot leak. Unfortunately, the plug does not extend through all the layers, probably because of the lack of a blood supply to the central and inner layers, which leaves the disc vulnerable to future tears.
Your doctor will provide stronger pain medication if necessary. You might also be given an epidural injection of a corticosteroid to relieve pain and reduce inflammation. These injections can provide relief for many weeks, but because of possible side effects, can only be given a limited number of times.
- Cold compresses, applied for 15 minutes at a time, several times a day, are helpful during the first day or two, followed by hot compresses.
- Acetaminophen (Tylenol), NSAIDs such as ibuprofen (Advil) or naproxen (Aleve) will provide pain relief and the reduction of inflammation.
- Try to avoid staying in bed. Prolonged inactivity will lead to weaker muscles and more pain.
A physiotherapist will have a variety of treatment options available, and will tailor the treatment to your particular needs. Such options might include massage, electrical stimulation, ultrasound, hydrotherapy and spinal realignment. You will also begin supervised low impact exercises, and be given advice on exercises to perform at home, leading to a gradual resumption of your normal activities.
Surgery is rarely needed, but if required will probably be one of three procedures. One would seal a leaking tear, another would be performed to shrink the disc enough that the size of the tear was reduced, and the third would be the removal of the damaged disc and fusion of the two vertebrae.
Annular Tear Prevention:
Nothing can be done to stop aging, and many annular tears do not produce any painful symptoms. However, staying as healthy and active as possible will reduce the risk of damage to the spine.
- Exercise to build muscle strength and improve flexibility.
- If you smoke, stop. Nicotine reduces the ability of the disc to absorb nutrients and will therefore hasten degeneration.
- Maintain a healthy weight.