I had the opportunity recently to discuss the importance of looking at the body, not as the sum of individual parts but rather as an entirety in itself. The nature of anatomy is to look at bits and understand them in isolation, the danger with this is that we gain only part of the picture, missing the subtleties in how these parts interact to form a magically supporting, moving, living, breathing whole person.

I had the opportunity recently to discuss the importance of looking at the body, not as the sum of individual parts but rather as an entirety in itself. The nature of anatomy is to look at bits and understand them in isolation, the danger with this is that we gain only part of the picture, missing the subtleties in how these parts interact to form a magically supporting, moving, living, breathing whole person.

Sometimes with the most common style of massage, it seems that we unconsciously enter into this conspiracy of parts by focusing our sessions or elements of our sequences on areas of the body – the arms – the legs – the back – the abdomen etc etc. As you saw in last months instalment, balance around the body is vital to the health and workings of the body. If we are to educate our clients then we need to extend our repertoire and our strokes to give a sense of integration and not of dissection.

One of the first things to notice about the arrangement in the trunk is how the abdominals (transversus, internal and external oblique) wrap themselves around the cavity, their fascia merging with that of the paraspinals. Learning from the two dimensions of a textbook it’s often forgotten that they go so far, we forget to palpate our partners on the couch; though think about it – if they didn’t, every time you coughed you’d look like one of those tropical frogs with your sides bellowing out as your insides had nothing holding them.

It is useful to see the abdominal cavity as a balloon, capable of being compressed from each side. We have the diaphragm over the top, the pelvic floor at the bottom (if you excuse the obvious pun) and the abdominals around the front and sides. The obvious examples of compression are when we contract the stomach muscles for forced exhalation or vomiting in one direction and defecation in the other but they alsohave a vital role in the support of the back muscles, particularly when we flex to lift a weight of some form.

Firstly lets review the muscles which are involved in the system. Working from six o’clock in the cross section we have the erector spinae group. Made up of the spinalis, longissimus and the iliocostalis, they are responsible for spinal extension and side flexion and join to form a common tendon in the lumbar area deep to, but part of the thoracolumbar fascia with the latissimus dorsi.

Look at the aponeurosis and think about the purpose of the lats, bringing the trunk upwards to curl over the ledge of a cliff or branch of a tree. Doesn’t it make sense to have its “origin” wrapped around the lumbar spine, supporting the centre of gravity and providing compression to the spine as the back flexes to pull the body up?

Further compression and, therefore, support is given to this easily abused area by the arrangement of the abdominals. The transversus wraps itself around the whole of the abdominal contents, its horizontal fibres contracting to squeeze the contents of the cavity, increasing the intra-abdominal pressure and pushing the internal organs upward against the diaphragm and down toward the pelvic floor. This seems to give the transversus three directions in which it gives support to the vertebrae and paraspinals. Firstly it acts to tighten the fascial bag in which the erectors, multifidi and QL’s are held (see cross section) giving them better efficiency in their contraction. But also with the forcing of the abdominal contents being pushed in opposite directions (toward pelvis and head) the resultant pressure helps to decompress the spine as it bends forward.

The transversus abdominis (TVA) will be assisted with this by the arrangement of the fibres of the internal oblique (IO), which also attaches to the thoracolumbar fascia.

Look closely at the diagram and you will see that the lateral fibres of the IO are nearly vertical any contraction here will further pull the superior/inferior ends of the thoracolumbar fascia together, giving extra resistance to the separation of the forward bend. This arrangement is calculated to take 12 – 36% load off the lumbar spine, a significant amount if you wish to keep a healthy spine for as long as possible.

In order to get a picture of this, watch someone as they bend forward, if you can see their back you may see their spinous processes pull away from each other. Now imagine you can see through their skin to what is happening underneath the skin. In an unsupp-orted forward bend, the front of the vertebral bodies get closer to each other as the posterior aspects (what you’ll see as the spinous processes) pull away from each other. This squeezes the disc material at the front, pushing it to the back of the joint capsule – you can model this using your own fist on top of each other to represent the vertebral bodies and the space between them as the disc and then tilting them one way and the other.

Unfortunately, the back of the joint capsule is less supported by the ligaments at the back than the front and the disc material can sometimes protrude or bulge out of its natural containment and may impinge on one of the nerves exiting from the vertebral foramen. This is one of the main causes of back pain and can be partly relieved and, more importantly, prevented by the correct usage and tone of the abdominal muscles.

The external obliques and the rectus abdominis are less directly involved in the support of the spine, but act to oppose the movements provided by the muscles of the back. Both will act to flex the trunk but the external oblique will also rotate the trunk to the opposite side if used unilaterally. As the external oblique attaches from the ribs to the iliac crest it can assist the quadratus lumborum (QL) in hip hiking (or that sexy wiggle beloved of salsa dancers and their admiring bystanders!).

The QL is involved in, but not necessarily responsible for, something like 85% of back pain and this is due to its role in stabilising the low back in an attempt to prevent further move-ment and therefore damage. Attaching from the iliac crest and rising up to each of the transverse processes of the lumbar vertebrae and the twelfth rib, it will “clamp” everything down in an attempt to splint the back and must be addressed to break the pain/spasm cycle that can develop.

The rectus abdominis travelling straight from ribs 5, 6, and 7 to the pubic crest acts purely to flex the trunk. One of the longest muscles of the body it is divided into sections in order to help prevent strains and gives us the much sought after six (or eight) pack look when highly toned.

The muscles of the back are often simplified, the erector spinae being taught as if it was one long muscle. As mentioned above it divides into three sections, each with a slightly different function and with quite a complex overlapping arrangement, which is worth further investigation by the dedicated student. I also want to mention the often ignored smaller and deeper spinal muscles, the multifdi, rotators and semispinalis, which underlie the erectors. While we may not be working on them directly, I have found that just knowing they are there helps to provide a more complete picture of how the body holds itself upright and coordinates its movement. It is these “evolutionarily” older muscles, which cross only a few vertebrae to provide the finer control of back extension and rotation and must be addressed in deep tissue work and some manipulative therapies.

To learn about the back and the trunk and how they, just move in your chair – side flex, rotate to one side and the other, flex and extend – feel how front and back work antagonistically, lift something from the floor using your abdominals and then not using them (please make sure you work within your limits!) attend a Pilates class and learn about the “zip and tuck” or the mulabandha and uddiyanabhanda of yoga.

In next months instalment we’ll look at the other muscles of the low back, which cross the hip and explore the triangular relationships around this joint.

References
Biel, A. 2001: Trail Guide to the Body, 2nd ed. Books of Discovery, Colorado.
Chek, P. 1993: Scientific Back Training. Chek Institute, California
Myers, T. The Abdominal Balloon.

Illustration reproduced with permission from the Trail Guide to the Body by Andrew Biel.

James Earls is a massage therapist and structural integration practitioner based in Belfast. He lectures on anatomy, palpation and various forms of massage in Belfast, Dublin and London, he can be contacted on 028 9059 0594.
James Earls 62 Greenore Street, Belfast BT6 8NF