Nerve Root Pain
The expression ‘a trapped nerve’ is often applied to any pain which is sharp, this is incorrect. The characteristic of nerve pain is that it covers an area distant from the problem that causes it and is consistent with the distribution of a single nerve.
Nerve Root Pain is one presentation of a trapped nerve and can be identified by reported ‘Symptoms’ in the distribution of a single Nerve Root and demonstrated by ‘Signs’ on a series of tests. The Nerve Root is the first part of each nerve in the ‘Peripheral Nervous System’:
Peripheral Nerves emerge from the spinal cord inside the spine as ‘Nerve
Roots’.
Nerve Roots exit the spine at each bone level through a hole called
the ‘IVF’.
Nerve Roots may then enter a ‘junction box’ called a
‘Plexus’.
In the Plexus the Nerve Roots mix to form ‘Peripheral
Nerves’.
The Peripheral Nerves then travel to the body with branches reaching
all areas.
Peripheral Nerves usually carry information both ways: Sensory signals (reports) travel from the body into the spine; Motor signals (instructions) travel out from the spine to the body. So the sensation ‘Touch’ is a Sensory report from the skin; and a movement results from a Motor instruction to the muscles. When a nerve is irritated it can cause disturbance of nerve transmission leading to pain, pins and needles, numbness (all sensory) or weakness (motor).
Nerve Root Pain is specific and applies to problems caused between the spinal cord and the plexus. Each Nerve Root has a reliable distribution and therefore a ‘signature’ pattern of sensory or motor symptoms. The Nerve Root is at greatest risk as it exits the spine when it passes through a small hole, the IVF, between the two adjacent bones (above and below), with the ‘Disc’ in front and the ‘Facet Joint’ behind.
The category of 'Back Pain' called ‘Nerve Root Pain’ is most appropriately applied when the nerve is irritated by disc damage as it prepares to exit adjacent to the Disc level above the IVF, or as it exits by the disc in front of the IVF. Disc damage is a comparatively serious but uncommon cause of back pain. The diagnosis of Disc damage (prolapse or herniation) leading to Nerve Root Pain is usually clear on patient reported history and examination. Your Spine Team practitioner will be able to confirm the likelihood of this being the cause of your pain, what it means to you and what can be done to investigate and treat it.
There are many patients who have mechanical or ‘Simple Back Pain’ which causes nerve irritation
giving low back and leg pain; or neck, shoulder and arm pain, but which is not
caused by disc damage. Soft tissue irritation to the Facet Joint and the
muscles and ligament which support it are a far more common cause of pain than
disc damage. Again your Spine Team practitioner will be able to help you
understand how likely this is to cause your pain and how it needs to be
investigated and treated.
