Back pain from a Mechanical point of view.
The cause of most back and neck pain is “mechanical”, meaning the source of the pain may be triggered by abnormal movement of the components of the spine.
Spine as a Machine:
Think about the spine as being a very intricate and integrated mechanical structure. The moving parts of the spinal column include ligaments, tendons, muscles, intervertebral discs, vertebral bodies and facet joints.
It is therefore made up of a number of inter-connected and linked moving parts. Between the base of the skull and the tailbone, there are usually 24 vertebral bodies (building blocks), many (facet) joints, the sacrum and tailbone. Binding all this together are ligaments, fibrous and muscular supporting structures, as well as the intervertebral discs (shock absorbers) sandwiched between the vertebrae. A balanced array of muscles provide stability and control the movement of the individual vertebra. Together these structures protect the spinal cord and nerve roots, and blood vessels.
Everything has to move and function in a balanced, coordinated and specific manner, like a fine piece of machinery, to distribute the body’s weight and stresses as we move about.
Our Lifestyle doesn’t help:
When the body is “static” (not moving or stationary, such as standing or sitting), different anatomical parts of the spine structure (such as the ligaments) continue to support the spine.
There are different mechanical forces at play (such as gravity, tension, compression, and stress) when we are either static or moving. These increase or decrease, depending upon our posture or movements. The spine is always working to balance these effects to help prevent injury.
Nowadays we tend to adopt postures and perform repetitive activities that our spine really isn’t designed to tolerate. This subjects the body to prolonged stresses on an ongoing basis, causing cumulative irritation which can overload the spine.
Think about how long many of us sit with prolonged stooped postures in front of a computer after a long drive to work. We then sit and drive back home, eat dinner and usually flop to sit in front of the TV to chill out. This repeated exposure to sitting (a prolonged, flexed (forward bending) posture) wreaks havoc on our supporting structures. They get irritated, over-heated, and the back muscles attempt to compensate, then get weakened and ‘out of balance’.
When this happens the spine has a ‘protective mechanism’ that kicks in. When there is an area under excessive stress, the muscles holding the vertebrae together will tighten up to brace and temporarily stop the vertebrae from moving too much so that it can the area of irritated spine to settle down and get back to normal. However, with the repetitive stresses we put on the spine every day these muscles can begin to stay ‘locked down’ indefinitely. This results in some areas of the spine with normal movement, and other areas with very limited, or blocked movement. Although the overall system continues to function, it’s now got a ‘glitch’, which results in abnormal movement and abnormal force / weight distribution patterns. It’s like an engine that goes out of tune, which causes it to overheat.
The supporting fascia – the ligament and disc binding structures of the spine have a poor blood supply (unlike muscles). Nutrients, oxygen and sustenance is obtained from surrounding fluids. The body usually uses the movement of the spine to create a ‘pumping’ mechanism to keep discs well hydrated with ‘hydraulic fluid’, (containing oxygen and nutrients), as well as to remove toxins from the discs, keeping them healthy. However, when the vertebrae with their joints and bones get ‘locked up’, this stops this ‘pumping’ mechanism from being as effective. The disc begins to dry out, break down and harden, causing micro-tears and cracks or ‘fissures’ to form inside the disc, with both inner and outer layers fraying. This is sort of like taking air out of a car tire, and can cause some bulging and loss of stability in the disc.
Eventually the disc and supporting structures of the spine get overloaded enough that they become inflamed, irritated and swollen. This swelling occurs in a fairly confined area and can start to irritate the nerves. The disc can also start to bulge or protrude enough to also cause compression of the nerves running between the vertebrae. This causes quite a bit of pain at the source (back or neck), and additional problems and issues in the parts of the body those nerves connect to (arms or legs).
Treatment essentially works around the principle that the spine must be ‘unlocked’ and the muscles loosened up, in order for the system to balance out and start working properly again. This reduces inflammation, allows healing and repair, and of course elimination of pain. A various combination of skillful chiropractic spine manipulation, massage therapy, McKenzie exercises achieves this effectively. Physical therapeutics may be necessary to help calm things down initially, then stabilizing exercises help strengthen things up for an integrated rehabilitation approach.