Physiotherapists are often asked this question. If you’ve ever had, or currently have, a disc injury to your lower back, you will understand why.
1. Annular Tear
In the 1950’s, it was discovered that discs actually have a nerve supply. Prior to that time, the tiny nerves that supply the outer fibres of the disc (annulus) had never been seen, thus the disc itself was thought to be insensitive to pain. Others since have elaborated that there is an overlap of these nerve up to 3 spinal levels above and below the affected disc. Following these discoveries, we know that the disc can itself be a source of pain, that this pain can be poorly localised due to this overlap, and that the disc may be unique in human musculoskeletal tissue in that the pain may mimic visceral pain more so than standard orthopaedic pain.
Annular disc injuries are typically degenerative in nature, though can also be the result of trauma. They will generally respond favourably to physiotherapy and guided exercises although patience and persistence is required.
The second mechanism is when an extruded or protruded disc comes into contact with the descending spinal nerves. This can cause unrelenting and severe pain into the legs, as well as sensory changes and muscle weakness in the lower limbs.
There is a common misconception that if there is material from a disc pressing against nerve tissue that it never heals, which is simply false. Discs can heal if the conditions for this are created.
The natural process of the human body to clean up the extruded material from the disc is called resorption and the pace of which this occurs can vary between individuals. This can be affected by genetics, systemic health, smoking & whether your activities or postures (especially repetitive bending and prolonged sitting) continue to provoke the disc.
Interesting to also note that MRI findings will lag behind improvement of leg symptoms (Ito, 1996) and that the larger the disc injury, the more likely it is to resorb (Maigne 1992, Bush 1992, Jensen 1996).
The most hopeful part about this information is that surgery to remove the disc material from being in contact with the nerve root is no longer indicated as an early treatment measure in most cases, as we know that the material will resorb over time.
Surgery should be urgently considered for a disc extrusion or protrusion if there is a change in bowel or bladder function (incontinence or retention) or numbness in the saddle area near the genitals or anus.
Otherwise, surgery is considered elective and is indicated only if:
- Progressive weakness of leg muscles is occurring & numbness is evident in the skin of the leg, and/or
- The pain is not manageable with conservative care
Conservative care for any disc injury includes physiotherapy, low weight-bearing exercise, rest from aggravating activities & postures as guided by your physiotherapist, and short-term pain relieving medication or injections into the affected area if required. Examples of low weight-bearing exercise are hydrotherapy and equipment Clinical Pilates guided by a physiotherapist to be performed across gravity.
It is extremely important to have these injuries assessed on a case by case basis as not all will respond to the same set of exercises. The simplest way to explain why is because disc injuries can occur in a 360 degree plane, and movements to a particular direction for one person will not automatically suit another. This is one reason why Clinical Pilates programs need to be tailored to the individual.
If this is happens to be a situation you find yourself in, you should:
- Seek guidance from a physiotherapist,
- Complete your rehabilitation,
- Incorporate healthy physical activity into your life
- Avoid provocative actions such as prolonged sitting, repeated bending or lifting with a flexed lower back
- Can be confident that your body will be working to help find the solution.
- Will reduce the rate of recurrent episodes
- Will give your disc the best chance of a full recovery.
And worth noting:
Around 50% of adults of all ages without back pain have disc abnormalities on MRI, with up to 30% having protrusions and 1-2% having the more severe extrusion. This likelihood increases with age. If you have lower back pain but no leg symptoms, the occurrence of disc abnormality on MRI may be coincidental and not necessarily linked to your pain (Jensen et al, 1994). If this is you, then physiotherapy and appropriate exercise is also your frontline treatment option.
To see one of our physiotherapists, please call us on 97510400 to make an appointment. They will guide you as to whether manual therapy, exercises, Clinical Pilates or a combination of either is appropriate.