Degenerative Disc Disease

The Disc

The disc consists of two separate parts. The outer part consists of a series of bands or rings called annulus fibrosus. To give an analogy of what this may look like, these bands resemble a sliced onion, and their behaviour can be described as a telephone directory rolled into a tube shape (very strong under compression). The central portion of a disc is called the nucleus pulposus and acts like a jelly substance that has a lot of fluid. Its behaviour resembles a spongy ball. Because every vertebra has a distinct shape in the thoracic, lumbar, and cervical spine, the function and structure of the disc also vary.

In the lumbar spine region, the main purpose of the intervertebral disc is to absorb shock and control compressive loads. It is important to note that the disc in any other part of the spine is not subjected to the same degree of compression because of the vertebral shape. This means that a disc issue in the lumbar spine is very different from a disc issue in the neck.

Biomechanics

When the intervertebral disc is subjected to compressive load, the central portion (nucleus pulposus) tries to expand sideways but is restrained by the rings of the annulus fibrosus.

The annulus is an elastic structure, but is more rigid than the nucleus, and it resists the pressure to deform – much like if you picture the metal rings on a wooden beer keg.

The pressure in the disc varies according to the position of the spine and how long the position is maintained.

Many people find it surprising that the disc is placed under significant pressure when sitting – a daily occurrence for many. This can be a little surprising, as sitting may not feel like much effort. It does, however, place continuous compression upon the disc. That’s also why it’s a good idea to get up, move around & change positions regularly even if your job does not require it.

Forward Bending (Spinal Flexion)

Bending forwards causes the front section of the disc to be compressed while the back portion gets stretched.

If this motion is conducted in a repetitive manner, such as in jobs that involve bending or hobbies like gardening, this can cause damages to the annulus fibrosus fibres and can lead to degenerative disc disease.

Forward Bending / Twist (Spinal Flexion)

Forward bending or twisting is a very common motion for many of us throughout our lives. However, many people with back pain issues will attest that this position is the culprit behind acute and sharp lower back pain, hence many chronic back pain sufferers try their best to avoid this position. Workspace safety training advice, especially in modules such as manual handling, includes avoidance of bending the spine and instead using the legs to compensate.

Unfortunately, despite several years and decades of rigorous training, the prevalence of pain injuries in the workplace has not been reduced. Under normal conditions, our pelvis, hips, and spine are designed in such a way that they can withstand the pressure of twisting and bending.

If the back gives out suddenly, it usually means there has been an underlying joint change (which is often ignored) and usually stays under the radar. This change alters muscle control and joint mechanics, hence predisposing the pain to injury. The most common underlying factors include poor muscle control i.e. spine stiffness, hips and pelvis, trunk and/or hip joints muscle control.

Mostly, the result of repeated low-grade trauma doesn’t generate any conscious awareness or inflammation. The inner part of the disc doesn’t have any nerve supply, therefore it can’t generate any pain sensation. It is when the condition worsens over time that symptoms are usually felt.

Symptoms of Disc Degeneration

Sciatica (nerve pain in the legs) is the most widely reported and recognized symptom of disc-related issues.

Some sciatica patients may also suffer from back pain, however, most of the cases are centred around leg pain. If the disc bulges but doesn’t compress any nerves, it may cause pain in the back region (primarily around the hip and buttocks section) and not down the leg.

If the disc itself is painful, it can produce a sensation of pain described as “deep” pain, and it may prove challenging to locate through the surface.

This pain may either be very sharp (it may be referred to as “nerve pain”) or it may present as a more generalised aching sensation that produces discomfort. A disc that is irritated but hasn’t yet prolapsed through the annulus fibrosus region may feel very vulnerable, similar to any other sprained structure like an ankle or knee ligament.

“Too much pressure” in the back region is another sensation often reported, and patients often report the need to lie down to ease the sensation.

Other Common Disc Degeneration Symptoms Include:

• Pain when sitting
• Pain when sneezing or coughing
• Pain during bending
• Pain while lifting
• Morning stiffness
• Pain when turning in bed
• Shoulders or hips shifted to one side (lateral shift)

Degenerative Disc Disease Treatment

Physiotherapy treatment options depend on the severity and stage of the condition. The first priority should be unloading the disc using support strapping, muscle activation, corrective exercises, or in some cases, a lumbar corset. It’s important to note that every effort should be made to prevent disc bulges from progressing to a full hernia, which requires surgical intervention. This is one of the main issues faced in using different techniques to “put the disc back”.

If the disc has shown some signs of recovery (which may take several days to several weeks), the next step in the rehabilitation process should be increasing movement, ensuring good postural muscular function, and increasing load tolerance with very carefully crafted and executed exercise sequences.

This is the most crucial part of the rehabilitation process and if it is not executed properly, it can easily cause a relapse.

Your Physiotherapist will prescribe exercise. This will be carefully and specifically selected, executed, and monitored.

In the final phase of the Physiotherapy rehabilitation process, all of the normal daily living tasks must be comfortable. The more advanced and challenging tasks related to your lifestyle should be incorporated into the physiotherapy rehabilitation program gradually.

For example, if your hobby is gardening, the physiotherapy rehabilitation program should focus on ensuring that your spine is fully capable of bending and tolerating that sustained position.

In some cases, this type of advanced flexibility might be problematic. For such cases, alternative ergonomic adaptations are required to facilitate the activity.

If the motive behind physiotherapist rehabilitation is to return to sporting activities such as tennis or golf, the advanced stages of rehab need to analyse the components that are involved in these activities, testing each one of these components in a controlled setting under proper supervision and then increasing the load to replicate the particular sport-specific activity.

Doing so requires your sports physiotherapy rehab process to involve a combination of specific manual therapies directed at the joints, coordinating the muscles, and specific corrective exercise, with some forms of simulated activity in a rehabilitation gym to prepare for the activities of daily life.

In summary, physiotherapy involves identifying and treating the painful structure and then addressing and treating the causative factors. Causative factors might be a combination of extrinsic factors (such as tools, workstation, time, position, breaks, etc.) and intrinsic factors (mechanics of the body). All of these elements need to be carefully assessed and treated by a qualified physiotherapist, which we offer here at DC Physiotherapy.