With normal standing posture, the low back has a slight curve, which is known as ‘lordosis’. When we bend forward or sit, we lose the lordosis and our lumbar spine – the low back – goes into flexion.  Spending too much time flexed, or performing heavy tasks in this position, can put a strain onto the lumbar discs. The ‘intervertebral disc’ is a structure that sits between adjacent vertebrae in the spine. It is composed of a tough, fibrous periphery with a gel-like nucleus in the centre. Repetitive or sustained flexion, as well as heavy lifts or bends, can injure the disc by causing tears in the fibrous rings. When this occurs, the gelatinous nucleus can bulge into the tear. In more severe cases, the gel can even push outside of the disc. It is most common for injury to occur in the back of the disc rather than the front.

To visualize what happens, imagine a jelly donut, where the dough is the fibrous outside of the disc, and the filling is the nucleus. Line up the hole that was used to fill the donut as being at the back/side of the imaginary spine. If you push on the front of the donut, the jelly will squeeze out toward the back, and can even push out of the donut (which would be the case in severe injury, or ‘prolapse’).  Forward bending is similar to this – there is an increased pressure on the front, and a suction force at the back, causing the gelatinous nucleus to move posteriorly if the fibrous rings are not holding it in place. Even with just an outward bulging of the disc (so, the jelly in the donut has moved but hasn’t escaped through the hole) can cause inflammation, and irritation of surrounding tissues, including nerves.

There are several strategies that can be used to help in the prevention of lumbar disc injuries. A few are:

• Use a firmly rolled towel, or a ‘lumbar roll’, in the curve of your low back if sitting. It is helpful to keep one in your vehicle
• Avoid the slumped position when sitting. A lumbar roll helps with this, as does your leg posture. Having your hips and knees in a deep bend, such as in a low chair, increases the forward bend in your back
• Take standing and walking breaks when traveling, or during long meals
• Stay flexible – tight hamstrings (backs of the thighs) in particular can have an effect on low back posture
• Keep a strong core to help support your back during activities. This doesn’t necessarily mean doing crunches or sit-ups, but exercises that target the deep core muscles
• During the post-holiday clean-up, avoid stooping to bend down to pick things up. Instead, bend your knees and hips to get into a good squat position. It’s a good way to exercise your legs, too!

Even with taking precautions, injuries can occur either with a single incident or over time. When this is the case and you notice you are having back pain, it is important to seek care from a health provider. Lumbar disc injuries, along with other causes of low back pain, can often be treated conservatively (meaning, non-operatively).  It is important to note that not all back pain is due to disc injury. A physiotherapist can help to determine what structure may be causing your pain, and give you appropriate exercises, stretches, hands-on treatment, and strategies for management, specific to your injury.