By Jakob van Vlijmen
M Chiro, DC
A Disc herniation is a protrusion of an intervertebral disc. These shock absorbing discs are situated between 2 vertebra and they allow for more elasticity and mobility of the vertebral column. The anatomy of an intervertebral disc is comparable to that of an onion; multiple layers on the outside and a gel in the centre of the disc. Through repetitive incorrect loading of the disc (i.e. prolonged bad posture or faulty lifting mechanics) the inner gel can press on and partly rupture the outer layers.
The back or spine consists of 24 vertebras, the sacrum, the coccyx (tailbone) and two hip bones. To be able to move smoothly our spine has little shock absorbing discs in between the vertebra, we have a total of 23 intervertebral discs.
A hernia in the lower back often causes back pain and always causes pain down one or both legs. A dull ache, pins and needles or a catching pain are common symptoms, when the symptoms worsen there is a possibility of loss of strength or numbness down the leg. Because the intervertebral discs aren't connected to many sensory nerves it is possible that the location of the herniation itself isn't painful meaning that even though the problem might be in the back, the only location where pain is felt is in the legs.
There are two possible causes for this. One is that the herniated or bulging disc is pressing against a nerve that travels into the leg, causing it to become irritated and producing a signal to the brain which the brain translates as pain in the leg. Another reason for the nerve to produce a signal is not physical compression but a build-up of chemicals in the area due to overuse and irritation of the IVD. These chemicals inflame the nerve and surrounding tissues resulting in the feeling of pain similar to that of a mechanical compression of the nerve.
Symptoms of a disc herniation can be very different from case to case depending on which nerve is being compressed and how severely. Lumber (lower back) disc herniation cause symptoms down the legs such as pins and needles and numbness. A disc herniation located in the neck is called a cervical disc herniation and can cause pain in the neck, pain towards the shoulder blade or into the arm.
Usually the disc bulges on the side, however it is possible that the bulge is pressing straight back which can, depending on the location, cause a ''Cauda Equina Syndrome''. This is a medical emergency as compression of the spinal cord in this manner can cause the loss of many bodily functions. Such as muscle control over the legs, bowel and bladder control and sexual function. The chiropractor is excellently equipped to recognise and act on such an emergency.
A disc herniation is a common injury to the back, which in only 50% of cases causes any pain at all. As people age the IVD lose their elasticity weakening the IVDs. The average age to have a disc herniation is between 20 and 45 years of age. Men are slightly more likely to have a disc herniation than women.
The ruptures in the IVD happen over time caused by bad posture or incorrect movement patterns. Having a static posture (which is the case with many jobs nowadays) increases your chances to develop a disc herniation as does lifting, repetitive bending and twisting the spine. In rare events a disc herniation can be caused suddenly due to severe trauma.
The chiropractor will be asking you questions about your back pain and general health to determine which factors contribute to your pain. Subsequently the Chiropractor will perform an extensive physical examination in which orthopaedic and neurological tests are used to determine which nerve is compressed. The results of these tests are combined with the information gathered during the interview to create a complete and comprehensive picture. There may be times when the chiropractor might deem it necessary to request further imaging most likely an MRI. This is the image modality of choice to asses a disc herniation, as it does not show up at all on an X-ray.
A Disc herniation can be a frightening diagnosis, it is important to know however, that research has shown that in 95% of the cases a disc herniation resolves spontaneously within 12 months. However, as this is quite a long period of time the chiropractor endeavours to shorten it by improving spinal function and helping patients return to optimal health as soon as possible. The Chiropractor uses many different techniques which are all focussed at optimising spinal function and taking some of the pressure off the compressed nerve. Not every disc herniation responds well to chiropractic care and for some of them surgery might be a necessity. If this is the case, your chiropractor will help you asses your additional options.