The vertebral column serves as a support structure for the human skeletal system and protects the nerves and spinal cord (soft, sponge-like tissue in the centre of the vertebral column) . It consists of 33 small bones called vertebrae which articulate with each other. Each vertebra is separated by a shock-absorbing cushion called intervertebral disc. These discs are composed of two parts: an outer fibrous ring and a jelly-like centre. They are designed to absorb shocks and pressure and to keep the spine flexible. The discs nest perfectly between the vertebrae.
Occasionally, increased intervertebral pressure or repetitive lumbar movement can weaken a disc. When this occurs, the outer fibrous ring ruptures and the centre, which is softer, bulges through the outer lining. This is known as a herniated disc. The herniation itself does not necessarily cause any problems. In fact, if part of the disc bulges forwards (towards the stomack), there are no symptoms and the situation resolves itself. However, if part of the disc bulges towards the back, the tissue can compress nerves, causing pain along the entire length of the nerve. Herniations most often occur in the lumbar or lower back area and can cause pain to radiate into the legs.Top view of the vertebral column
Physically active people between the ages of 35 and 55 years have the greatest risk of developing a herniated disc. In fact, with age, the intervertebral discs become less flexible. As a result, the spine loses flexibility and tone, making it more difficult to perform physical activities. An awkward movement or excessive strain when lifting an object can also cause a herniation. Being overweight, pregnant or having bad posture can increase pressure on the back and predispose individuals to herniated discs.
The symptoms associated with herniated discs depend on the location and pressure exerted on the nerves. A herniation can cause pain, muscle weakness, tingling and stiffness. Depending on where the herniation is located, pain can radiate throughout the legs or abdomen (stomach). In rare cases, herniations can develop in the neck area. In such cases, pain can spread through the shoulders to the chest and arms. Pain may be exacerbated if the back muscles are solicited.
Herniated discs are diagnosed by a physician. The physician will go over the patient's symptoms and conduct a physical examination. However, to examine the spine and make sure there are no underlying problems, various tests may be ordered. Diagnostic tests may include a scintiscan, computerized axial tomography (CAT) or magnetic resonance imaging (MRI). These medical imaging tests provide two or three dimensional images of the spine and surrounding tissues.
Rest is often the only treatment for a herniated disc. Medication may also be taken to relieve pain and reduce inflammation. Manipulation of the vertebrae, aimed at reducing pressure on an intervertebral disc, can be performed for certain types of herniations. In rare cases, surgery may be recommended.
Here are a few measures that could help prevent a herniated disc:
- Good posture - especially when seated for prolonged periods: back straight, both feet flat on the floor or on a small footstool so that the knees are higher than the hips.
- Maintain a healthy weight.
- Warm up before exercising and stretch afterwards.
- When lifting objects: bend knees, keep object close to body, keep back straight and lift with the legs.
- When shovelling snow in winter: lift with the legs, keep the back straight and send the snow forwards rather than twisting the trunk.