FAQ: Sciatica

1) What is Sciatica?

Sciatica is the term commonly given when pain is referred down your buttock or leg. It may involve burning, tingling, pins and needles, aching, sensory changes (hot and cold sensations) and sharp shooting pain.

It is most commonly caused by a disc bulge in your lower back, where the disc is bulging far enough to touch the nerve (the lowest three nerve roots, located behind the 3 lowest discs in your lower back, join together to form the Sciatic nerve, hence the term “Sciatica”.


2) Are there other causes of Sciatica apart from the disc bulging onto the nerve (mechanical compression)?

Sciatica can also occur by chemical irritation (inflammation released from the tear inside the disc), and sometimes this requires anti-inflammatory medication/nerve specific medication to address this component of your problem. This is called Chemical Radiculopathy (Radiculopathy is just a scientific term that means nerve pain).  The more common cause is certainly mechanical compression of the nerve via the disc bulging, but your McKenzie Physiotherapist is well skilled at identifying your particular cause and therefore treatment required.


3) What Causes Disc bulging in the first place if this is the cause of my Sciatica?

The short answer is lifestyle!

The spine has normal curves, including a Lumbar LORDOSIS (natural curve in the lower back). Loss of the lordosis occurs with many lifestyle positions on a frequent basis.

Loss of the lumbar lordosis whether prolonged (eg. Slouched sitting or sleeping curled up) or repeated (eg. This occurs with many daily activities such as vacuuming, emptying the dishwasher, ironing, putting make-up on or shaving) starts to put excessive loading on the discs and ligaments.

Initially this increase in loading on the spine caused by regular loss of the lordosis puts strain on the soft tissues such as the ligaments in the spine. At this stage pain is felt while sitting slouched or bending, but quickly disappears once you get out of the offending position. As the process continues with SLOUCHED SITTING and repeated bending, overstretching of the ligaments occurs, and as they weaken over time this then starts to cause loading on the disc leading. This excessive loading on the disc causes weakening of the cartilage inside it. If not corrected this then leads to bulging of the disc.

If this overloading from regular loss of the lordosis is not corrected (posture is the key!!!) the disc can bulge far enough to touch the nerve behind it, giving rise to radicular symptoms in the leg called (Sciatica).

While some people lift something heavy to trigger their back pain, more often the thing that starts the pain is something trivial like a bend forward (especially in the early hours of the day after waking), getting up from sitting or a sneeze. This is as poor lifestyle habits have begun weakening and damaging the disc long before pain arises, and this trivial movement is the last straw.


4) Can the McKenzie Method fix my Sciatica?

For the vast majority of patients the answer is YES!

The McKenzie Method involves an assessment where we specifically look for the Specific Exercise that will push the disc off the nerve and give you relief of the Sciatica.

While the disturbance in the resting position of your disc may be considerable (potentially making you lean forward, unable to stand upright, or lean over to one side) and symptoms may be severe the exercises are designed to rapidly reduce disturbances of this nature and relieve nerve compression.


5) Is the McKenzie Method going to fix my Sciatica long-term?

As mentioned above the key reason you likely developed this issue is poor posture and lifestyle factors. We educate you from the very first session how to address these issues, resolve your current episode and then teach long-term strategies to ensure these episodes of Sciatica are a distant memory.

6) I have been told I have a Spondylolysthesis? What is that and is it causing my Sciatica and/or back pain??

This refers to a “slip” of one vertebra on another. This most commonly occurs as a congenital condition (from birth) and is most commonly NOT the cause of your symptoms. The “slip” occurs because part of the vertebra called the Pars Interarticularis fails to form correctly at birth, allowing excessive translation of those two vertebra.

While many of these patients are told by some Allied Health Professional “Never arch backwards” it is the most common movement these patients require to ease their pain. The reason for this is that frequently the disc above or below the “slip” is the cause of their pain and not actually the Spondylolysthesis.

Ultimately a McKenzie Assessment is such patients is safe and provides the answer as to which is generating the pain, and therefore which treatment exercise is required.  

A minority of patients do actually have an active Spondylolysthesis generating their pain. The Assessment process identifies this, and these people often get a bone scan to confirm. These patients are very rare and usually involve extreme extension loading (fast bowler in cricket who is doing a huge volume of bowling).


5) I have Sciatica but my scan (MRI or CT) shows I have Canal Stenosis. Is this the cause of my Sciatica and what is Canal Stenosis?

Canal stenosis refers to narrowing of the Spinal Canal (Stenosis means narrow). The Spinal Canal is the space behind the discs (in both the back and neck) where the Spinal Nerves exit. If the canal is compromised enough, the nerve root passing through it is squashed and gives rise to Sciatica.

The Stenosis or narrowing is more common as you get older (usually over 55+) and can be structural (Bony narrowing by spurs that develop with the wear and tear of living called Osteophytes), narrowed due to disc bulging (ie. disc bulging into the Canal means less room for the nerve), or a mixture of both (disc bulge/osteophyte complex).

The answer to which is causing the Sciatica can only be determined by taking you history and correlating it to both your scan results (many scans show findings that do not relate to your current symptoms!) and your response to repeated movements.

Many patients experiencing leg pain with walking and are told they are suffering from Canal Stenosis and require surgery.

Many such patients respond to exercises that affect the disc. While they still have a likely narrowed canal structurally, the extra room created for the nerve by pushing the disc back in relieves all the symptoms.

Other patients respond to Flexion exercises (that open the space around the nerve in the canal) taking the pressure off the nerve, and will not require surgery or exercises for the disc.

A thorough McKenzie Assessment will provide YOUR particular diagnosis and determine what you need to resolve your problem.