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Terminology and Definitions

You may hear this condition/injury called many different things. Sometimes people mean the same thing when they use these terms interchangeably, but technically they refer to something different.

Understanding what might be going on in your back is a good place to start, as there is often a lot of fear around disc related injuries, particularly if there is misinformation or misunderstanding about what is happening in your body.

In saying that, it often doesn’t really matter because what is most important are your symptoms and level of function. Unless we are looking at an injection or surgery we treat most of these things very similarly.

Disc Degeneration– Age related changes in the overall health of the disc
Disc Strain/Overload– A strain or overload of the disc from recent increase in load or pressure eg. Prolonged or repetitive flexion/bending or heavy lifting
Disc Bulge– A disc in which the outer margin extends over a broad base beyond the edges of the disc space.
Disc Herniation– Localised or focal displacement of disc material beyond the normal margin of the intervertebral disc space (includes protrusion and extrusion)
(Fardon et al., 2014)  

Your physiotherapist will be able to provide further clarification and education in regard to your specific diagnosis.

What is happening and why does it cause pain?

The intervertebral disc is made up of 2 components. A tough outer ring called the Annulus Fibrosus (Annulus) and a more liquid type inner filling called the Nucleus Pulposus (Nucleus). An analogy we can use to explain this is to think of a truck tyre filled with chewing gum, a firm outer ring with a softer more ‘jelly like’ substance in the middle. Occasionally, we hear discs being compared to a jam donut, but this analogy does not capture how strong and robust the disc is.

In simple terms, typically when we bend forward (flexion) the nucleus is pushed towards the back of the disc creating an increased pressure on the annulus/back of the disc. This can lead to strain/overload or in more severe cases bulging/herniation of the disc.

As with everything related to the human body, it is not always quite that simple with many other factors potentially contributing to discogenic injury and pain.

Once the disc is overloaded/stirred up, pain may be experienced around the lower back or into the buttock, hip and groin. As we will discuss later in this resource, the disc may also interact with the nerve roots that exit the spine close to the disc via mechanical compression or chemical irritation, and this is where leg pain or neurological symptoms such as numbness, tingling, pins and needles and/or weakness may be experienced.

It should be noted that the disc and spine in general are very strong and robust structures which can tolerate a high degree of movement and load. The discs are firmly attached to the vertebrae and do not slip in and out of place. 

Dermatomes and Myotomes

The spinal nerve roots exit the spine very closely to the disc through the intervertebral foramen (see picture above) and can be affected by either mechanical compression eg. from disc material or chemical irritation eg. inflammation.

If the spinal nerve roots are affected, they may cause changes to a dermatome or myotome relating to that specific nerve root/spinal level. This can help us determine where your injury is occurring and can be used to correlate your symptoms with imaging findings if you have had a scan.

Dermatome = an area of the skin supplied by nerves from a single spinal nerve root.


Myotome = a set of muscles innervated by a specific, single spinal nerve root.
L2 – Hip flexion
L3 – Knee extension
L4 – Ankle dorsiflexion
L5 – Big toe extension
S1 – Ankle plantarflexion

Do I need a scan? The role of imaging & interpreting imaging findings

This is a really common question we get asked with many clients believing a scan in necessary to diagnose and treat back pain.

Generally, getting your back scanned/imaged is only indicated in the presence of severe neurological symptoms eg. severe pain, numbness, weakness or an inability to control bowel or bladder. In the absence of these symptoms we would only encourage imaging if we think it would change our management of your injury. When we say “change your management” we are referring to whether we would consider an injection or surgery. If not, then there is not much benefit of performing a scan and conversely, there may be negative outcomes associated with inappropriate or unnecessary early imaging (RACGP, 2022).

There are many things that may show up on a scan that are not responsible for your symptoms. There have been multiple studies where they have scanned asymptomatic patients (patients with no pain or symptoms) and shown high rates of these ‘abnormal’ findings (Brinjikji et al., 2014).

Additionally, we know that disc injuries can heal and have the ability to completely resolve without surgical intervention (Chiu et al., 2014).

But as we’ve discussed, even if it doesn’t ‘heal’, that doesn’t mean you will still have pain or disability because we know these things can be present and not cause pain. 

Decisions about whether or not imaging is appropriate are made on an individual basis depending on the specific circumstances of your injury and presentation.

(Brinjikji et al., 2014)

So… how do we treat it?

Calm it down.
Build it back up.

It is good to know that most lower back pain is not serious and gets better on its own.

“In general, the clinical course of an episode of acute low back pain seems favourable, and most pain and related disability will resolve within a couple of weeks. This is also illustrated by the finding that about 90% of patients with low back pain in primary care will have stopped consulting their doctor within three months” (Koes, van Tulder, & Thomas, 2006).

We often break down Discogenic Low Back injury management in 3 phases:
Phase 1. Settle down your acute pain
Phase 2. Return to activity/function
Phase 3. Prevent reoccurrence

In the early phase of your rehabilitation we may consider things such as
– educating you about your back pain (this is what we are doing now!)
– limiting your flexion loading eg. bending, sitting and lifting
– avoiding prolonged positioning/changing position frequently (keep moving!)
– hands on/manual therapy (see details later in guide)
– starting an extension based exercise program (see details later in guide)
– encouraging gentle/comfortable movement
– simple pain relief strategies eg. heat and paracetamol
– consider anti inflammatory medication

Hands on treatment
– the role of manual therapy?

Your back does not need to be “fixed” and there is nothing we can do that will “fix your back”. We can not manipulate the disc back into place or re-align your spine. The discs don’t slip out of place and your spine doesn’t either.

However, manual therapy can be very effective in modifying/relieving symptoms which will allow you to move easier and be more comfortable in the early stages of your rehabilitation. We may use a range of hands on treatments to assist you, including but not limited to:
– Mobilisation
– Mobilisation with movement
– Soft tissue massage
– Dry needling

Other treatments your physiotherapist may recommend include:
– Taping
– Lumbar support pillow/towel roll
– Heat

Extension based exercise program

We discussed earlier how bending forward increases pressure on the back of the disc. Conversely, this concept means that arching back/extension may relieve pressure on the back of the disc and hopefully reduce your symptoms.

Example: Extension in Lying

Despite these exercises being very commonly prescribed for Discogenic Low Back pain, there are many other ways to manage this condition and there is no ‘one size fits all’ program.

Exercises will be prescribed on an individual basis taking into account the specific presentation and factors relating to the person with back pain.

What if things don’t improve?

Typically we would advise giving yourself 3 months of physiotherapist led rehabilitation before looking into getting a scan or further invasive treatments such as an injection or surgery. This is of course, in the absence of any severe neurological symptoms and provided things are getting better and not getting worse.

If things have not improved to an acceptable level after 3 months we may consider referring you for a scan and/or specialist opinion.


Brinjikji, W., Luetmer, P. H., Comstock, B., Bresnahan, B. W., Chen, L. E., Deyo, R. A., … Jarvik, J. G. (2014). Systematic literature review of imaging features of spinal degeneration in asymptomatic populations. American Journal of Neuroradiology, 36(4), 811–816. doi:10.3174/ajnr.a4173

Chiu, C.-C., Chuang, T.-Y., Chang, K.-H., Wu, C.-H., Lin, P.-W., & Hsu, W.-Y. (2014). The probability of spontaneous regression of Lumbar Herniated Disc: A systematic review. Clinical Rehabilitation, 29(2), 184–195. doi:10.1177/0269215514540919

Fardon, D. F., Williams, A. L., Dohring, E. J., Murtagh, F. R., Gabriel Rothman, S. L., & Sze, G. K. (2014). Lumbar disc nomenclature: Version 2.0. The Spine Journal, 14(11), 2525–2545. doi:10.1016/j.spinee.2014.04.022

Koes, B. W., van Tulder, M. W., & Thomas, S. (2006). Diagnosis and treatment of low back pain. BMJ, 332(7555), 1430–1434. doi:10.1136/bmj.332.7555.1430

RACGP. (2022). Retrieved from https://www.racgp.org.au/clinical-resources/clinical-guidelines/key-racgp-guidelines/view-all-racgp-guidelines/first-do-no-harm/gp-resources/imaging-in-adults-with-acute-low-back-pain