What exactly is a ‘slipped disc’?

Did you know that an estimated 80% of the population worldwide will, once in their lives, experience lower back pain? A major cause of this pain can be a slipped disc in the spine. In today’s blog we explain the structure of the spine and what the term ‘slipped disc’ means. We also explain how physiotherapy can help in treating, preventing and protecting against this type of pain.

The structure of the spinal column

The human spine consists of 33 separate bones of different shapes and sizes, stacked on top of each other. These are the vertebrae.

In between the vertebrae are flat, round discs. They each have a tough, outer layer – the annulus – that surrounds a jelly-like material – the nucleus.

The main role of the discs is to act as shock absorbers for the vertebrae. They absorb forces every time you move or perform high-intensity activities such as running and jumping.

Herniated discs

A herniated disc (also referred to as a bulged, slipped or ruptured disc) is a fragment of the disc nucleus that protrudes out of the annulus into the spinal canal. It usually happens because of a tear or rupture in the annulus. Discs that become herniated are usually in the early stages of degeneration.

The spinal canal is a narrow space, too narrow for the spinal nerve and the displaced herniated disc fragment. Because of this, the displacement causes the disc to press on spinal nerves. The resulting pain can often be severe.

The areas in the back that are most affected are those with the most mobility – the neck and lower back. The midback is, in general, less affected.

What causes herniated discs?

There are a few factors which mean you may be more susceptible to suffering from herniated discs. These include:

• Genetics
• Family history
• Lumbar load
• Poor core stabilization due to weak muscles
• Smoking
• Weight-bearing sports
• Certain work activities, such as repeated lifting.

Diagnosing herniated discs

Magnetic resonance imaging (MRI) is widely used to confirm suspected disc herniation. The diagnostic accuracy is 97%. However, magnetic resonance imaging findings of herniated disc are not always accompanied by clinical symptoms.

Not all people with herniations are symptomatic. Therefore, the diagnosis and therapy must correlate with the patient’s complaints, physical examination findings and clinical history. These factors also help a medical practitioner determine the extent of the disc damage.

Symptoms of a herniated disc

The pain which accompanies a slipped disc is caused by the disc pressing on a nerve in your spinal column. This can get worse if there is any further pressure placed on the nerve, for example if you sit down, cough or sneeze. This pain will typically settle down in one to three months. However, it can last a lot longer and there is also a chance of it recurring in the future.

Symptoms of slipped discs vary depending on where they are in your back; neck/ mid-back or lower back.

The most common spinal level to get a disc herniation in the lower back is located between L5 and S1.

Symptoms may include:

• Numbness or tingling in your shoulders, back, arms, hands, legs or feet (depending on the level of herniation).
• Constant severe or sharp pain, especially during the acute phase.
• Inability to move the neck and lower back in its full range of motion.
• Most painful movements will often be bending forwards. Activities such as putting socks on, tying shoes and sitting on a chair will trigger pain.
• Depending on the severity of symptoms, range of motion can be extremely limited in the neck and lower back
• Inability to find a comfortable position to stand, seat or sleep.
• Muscle weakness (again, depends on the level of the herniation).
• Pain in the buttocks, hips or legs if the bulged disc presses on the sciatic nerve (sciatica).
• Loss/reduction of sensation in the arms/hands/legs/feet.

What happens next?

Most people who experience disc herniation require no surgery. About 90% of these patients report an improvement with non-operative treatment within 3 months of the onset of their symptoms. Conservative management is the most common treatment.

Physiotherapy

Physiotherapy treatment plans depend on the severity of the symptoms and the individual themselves. They also offer a low-risk rehabilitation solution. The physiotherapist will focus on specific exercises and advise the patient on how to; manage their symptoms, improve mobility, reduce pain, and return to their usual, everyday activities.

Injections

Local corticosteroid injections (CSI) are a commonly-used technique for both the diagnosis and treatment of disc herniation.

How can you prevent herniated discs?

There are several things individuals can do to strengthen and protect their spines from disc herniation.

• Focus on exercises to improve core strength and stability.
• Use correct lifting and moving techniques, such as squatting to lift a heavy object.
• Maintain correct posture when sitting light/ heavy objects and standing.
• Follow a healthy lifestyle, improve your diet, quit smoking, sleep 7-8 hours every night, increase your water intake, be more active.
• Maintain a healthy weight. Extra weight might overload and put more strain on the lower back.

Further Investigation

In some cases your back pain may need further investigation. When back pain is accompanied with the following specific symptoms you should go to your GP. For instance if you:

• Have difficulty passing urine *
• Lose control of your bowels *
• Develop numbness around your back passage or your genital area *
• Develop erectile dysfunction *
• Have weakness in your legs or you are unsteady on your feet *

Or if you have:

• Severe pain going down both legs into your heels *
• Had a direct trauma to your back *
• A history of cancer
• Very severe pain through the night
• Rapid onset of weight loss

*If you develop these symptoms you should attend your local A+E department for urgent investigation.

What should I avoid with a disc injury?

One thing to remember when seeking help is to understand there is no quick fix. Do not listen to bad advice which may include:

• You need to bed rest/rest for long periods days
• If your pelvis is out of line and needs adjusting
• You have one leg longer than the other – so you are always going to have back pain
• Avoid lifting heavy objects and avoid bending over