Intervertebral disc

Intervertebral discs are located between the vertebrae of the spine. They are an important structure in the back. The intervertebral disc is often cited as the cause of back pain. People also think it has slipped when someone has "thrown their back out." Many people are also afraid that intervertebral discs are easily damaged. But is this true?

Anatomy of the intervertebral disc

Between two vertebrae of the spine lies an intervertebral disc, 23 in total. This creates space between the vertebrae so they can move relative to each other. In addition, an intervertebral disc provides strength and holds the vertebrae together. There are no intervertebral discs between the highest cervical vertebrae and the lowest vertebrae at the tailbone.

The intervertebral disc consists of a strong outer ring of connective tissue, the annulus fibrosus. This ring has different layers. The ring surrounds the gel-like centre of the intervertebral disc called the nucleus pulposus. The gel-like material consists of loose fibres and proteins. The nucleus pulposus helps distribute pressure and protects the vertebrae from high loads.

The intervertebral disc is attached to the vertebra by an endplate. This endplate consists of bone and cartilage and is extremely strong. This makes it impossible for the disc to slip. Blood vessels in this endplate supply nutrients to the intervertebral disc.

Function of the intervertebral disc

The intervertebral disc has a shock-absorbing function. The discs absorb and distribute the forces acting on the spine. Due to its structure the disc absorbs both compressive and tensile forces.

An intervertebral disc consists mainly of water (80-85%). Many nutrients are dissolved in this water. The functioning of the disc is determined by the quality of these components. Due to pressure on the disc, nutrients are exchanged via the endplate with the blood in the body.

During high pressure, water is pressed out of the disc. When the pressure is removed, it can take up water with nutrients and building blocks again. It works like a sponge. Regular loading is therefore very important. The supply of new nutrients keeps the disc in good condition.

Conditions

When the gel-like substance no longer transmits forces properly, symptoms can arise, especially with shuffling and sitting or standing in the same position for a long time. This gives patients a feeling of stiffness in the back. In this case there is too little fluid and nutrients in the disc.

When the disc retains too much fluid, there are mainly complaints of morning stiffness when bending and putting on socks. Retaining too much fluid occurs when the ligaments around the disc become lax. The ligaments then no longer compress the disc. Due to too little pressure there is less exchange of waste and nutrients, so the water remains in the disc and contains insufficient nutrients.

A well-known condition of the intervertebral disc is a hernia. In a hernia the soft core of the disc bulges out. This leads to back pain. The symptoms can also radiate to one or both legs due to pressure on a nerve.

Recovery of the intervertebral disc

The recovery process is determined by the availability of sufficient nutrients. Under ideal circumstances recovery occurs automatically. There must then be a sufficient supply of nutrients. This supply is optimal when the spine moves well. A blockage or instability of the back can disrupt this.

Many problems of the intervertebral discs resolve on their own. If this is not the case, a physiotherapist can help.

It is important during recovery to match the load to the load capacity of the disc. The healing time of the connective tissue in the disc is a few weeks. The connective tissue around the disc needs three months to heal.

When the balance between load and load capacity is not right, recovery cannot take place. The body then 'looks' for adaptations. This can result in spondylosis. Spondylosis is wear and tear of the spine. The spine stiffens from the vertebrae. This stiffness compensates for the resulting instability. There will also be changes in posture and movement of the spine. Recovery therefore takes even more time. Recovery is also strongly age-dependent.

Rehabilitation for intervertebral disc complaints

Rehabilitation always involves movement-dependent loading. This means the back must be trained in different movements. Not only straight, but also sideways and with rotations of the back. Depending on what the disc can handle at that time.

Through movement there is an exchange of nutrients. It is therefore important that all vertebrae move well (again). By means of mobilisations or manipulations any blockages are removed. If optimal recovery is no longer possible, the aim will be to achieve the right compensation. Even with compensation, completely pain-free movement is possible.