Have you ever heard someone complain about their bulging disc or disc prolapse? Or ever worried that the pain in your back is a ‘slipped’ disc? These are phrases that people talk about quite often when they come into the clinic, but do you actually know what they mean? What is a disc? And is it serious if you injure one?
The intervertebral discs are fibrocartilaginous shock absorbers that sit between adjacent spinal vertebrae. They allow the bones in your spine to move as they adapt to changes in direction and pressure as you go about your day, and also provide stability for the spinal column. The outer part of the disc is called the annulus, and is made up of tightly packed layers of tough but flexible fibrocartilage, while the internal part of the disc, the nucleus, is made of a jelly-like substance called glycoprotein.
Injury to the disc usually occurs as a result of poor lifting technique, repeated load or poor posture, but there are other factors such as age, smoking and obesity. Commonly, these issues contribute to poor core control or stability, which means the discs in the spine are exposed to greater forces than they can withstand, and are vulnerable to injury. Discs can be gradually injured over time in a vague pattern, or injury can occur suddenly and severely.
If the annulus of the disc is damaged, the inner nucleus can bulge outwards, placing pressure on nearby structures and causing pain. If the nucleus completely breaks through the annular layer this is known as a herniated disc. The disc itself is tightly adhered to the vertebrae above and below it, so it cannot ‘slip’, which is a common misconception. Rather, the inner material bulges or herniates outwards, and occupies more space than usual. This can become a problem if this material starts to place pressure on the nerves exiting the spinal cord, or the spinal cord itself.
The most common area for disc injury is the low back, followed by the neck. People with disc bulges or herniations may experience pain in the local area, with referred pain and numbness or tingling along the path of the affected nerves, eg down the arm or leg. There may also be some restriction of movement, especially into flexion or forward bending, as this compresses the disc further. Activities, which place extra, pressure on the spine such as lifting, straining, coughing or sneezing may increase pain as well. Diagnosis of a disc bulge is based on the medical history and physical examination, but can be confirmed with imaging eg MRI, CT. It is also important to note that some disc problems can be completely asymptomatic, and are only discovered when imaging is performed.
Pain caused by disc bulges can be debilitating and even frightening, but with treatment, medication use eg anti-inflammatories, and some good advice regarding exercise and rehabilitation, they can improve quickly. Osteopathic treatment for disc bulges involves the use of soft tissue massage, joint mobilisation, stretching, traction or dry needling, and may have good results in most cases. Some people may have ongoing pain and limitation of movement that can take a lot longer to resolve, and in some cases, a course of localised injections or even surgery may be required.
Over time, the torn fibres of the annulus will heal as scar tissue forms, and the displaced nucleus will gradually be reabsorbed, but it is highly likely that the disc will be weakened and prone to injury in the future. This is why it is important to adhere to the advice you are given by your health care providers – prevention of re-injury is vital! Once pain decreases, it is commonly advised that core strengthening be part of the rehabilitation program, for example, clinical pilates or swimming, which can help reduce the risk of re-injury, and maintain good spinal health in the future. For most people with disc bulges, they are simply one aspect of their overall health that needs to be managed, and when they are under control, they may not even think about them.
So if you have been diagnosed with a disc bulge, take some time to try and understand the condition and what it means for you. Ask lots of questions! If you understand the nature of your pain and what to do about it, the fear that comes with it can be greatly reduced, and you will be able to approach the treatment plan and rehabilitation without trepidation. After all, knowledge is power!