McGill and Back Strength

Reviewed by Stew Wild

Tensegrity can be likened to a system of struts and cords holding a semi-rigid structure together, but allowing some movement, like the Golden Gate bridge. Prolific examples occur in every living cell in the body. One of the first to recognise this type of structure was Buckminster Fuller. He investigated how nature used this tension and compression system to allow movement without loss of stability. Tensegrity structures are designed to be flexible, strong, and resilient; can absorb or disperse shock; and can pass on communications in the form of vibrations, chemicals and possibly as yet other undiscovered means. Each biological cell has tensegrity, each organ has it, and each organism has it.

A good example of a tensegrity structure in the body is the spine. If we were built like a stack of blocks (think of the famous Rolfer’s depiction) we would be rigid, unwieldy and top heavy. Instead, we have a spine made up of vertebral bodies, spongy spacers (discs), a central canal to protect the spinal cord, and lots of bits sticking out for muscles to obtain extra leverage. Remarkably, the vertebral bodies are made of cancellous bone not compact bone. This means they are not solid but finely honeycombed. Why? Well, for one it will save weight, but maybe another reason lies in the system of struts and cords that surround each vertebra.

If all the myofascial paraspinal components of the spine exhibit a good balance between strength and flexibility the diagonal alignment of these cords may in fact help lever the vertebral bodies apart on the disc. To support this theory the origins and insertions of the muscles need to be reversed. In the thoracic spine the ribs expand in a “bucket handle” manner with correct breathing. They lever the thoracic vertebrae apart from each other using the diagonal action of the internal and external intercostals muscles with each breath. This ‘vertebral decompression’ with breathing may help to explain why the vertebral body doesn’t need to be made of compact bone (Leon Chaitow estimates breathing patterns disorders in over 60% of back pain sufferers).

Further down in the lumbar spine we don’t have ribs to help with tensegrity. (Is this why low back pain (lumbar) is more problematic than thoracic back pain?). What do we have instead? For one we have the amazing Quadratus lumborum muscle, plus the internal and external obliques, transversus abdominus, and deeper down the multifidis and rotators (and don’t forget about the diaphragm and psoas too). Note that most of these muscles have fibres lined up in the diagonal. They can pull up, down and across. It’s well known that when we injure our back multifidis is one of the first muscle to atrophy and one of the last to rehabilitate. We must never discount the influence of a breathing pattern disorder, meaning the ribs and diaphragm aren’t exerting their influence on rib 12 then a whole sequence of events may lead to an unexplained back pain.

A tensegrity structure relies on gravity as the force it works against. It requires a bit of educated bodywork and movement therapy to fully rehabilitate a compromised tensegrity structure. Much of the rehabilitation involves recognizing the compromised structural, functional and emotional stability both as a local event and as a whole body event. Dysfunction may appear as asymmetrical bony landmarks, muscle imbalances, altered movement patterns, compromised energy systems as well as altered states of mind.