John Martin Littlejohn - Triangles of Force Made simple

THIS ARTICLE IS A WORK IN PROGRESS - IT WILL BE FINISHED IN THE COMING WEEKS

John Martin Littlejohn developed a theory on the mechanics of the spine and in the 1985 Yearbook of the Maidstone College of Osteopathy John Wernham explains the theory. This article is not meant as a substitute for the original text. The original contains a more detailed explanation of the theory and also provides very useful diagrams. I have tried to simplify the article which can be complicated and confusing as a springboard for others to go and return to the original.


Anterior- Posterior and Posterior-Anterior Gravity Lines:

John Wernham, for the sake of this study divides the "body" in to 2 parts - the vertebral column and the pelvis and finds the centre of gravity within them. To find the centre of gravity he draws 2 lines – the anterior-posterior gravity line and the posterior-anterior gravity line.

Anterior-Posterior Gravity line:
The anterior- posterior line is a line drawn from the upper to the lower limits of the body; that is, from the anterior margin of the foramen magnum to the end point of the coccyx. On its journey it crosses the posterior junction of L4/L5 and the body of S1 to get to the point of the coccyx.

Posterior Anterior Gravity line:
The second line is drawn from the posterior margin of the foramen margnum to the anterior most part of the spine – L2/L3 at which point the line splits to both femoral articulation in the acetabulae.

For reasons that are explained in the original article, the resultant ( a term used in physics) of these two lines passes through the body of L3 vertebrae and it marks the centre of gravity. The importance of this is that it means that the entire body above is supported on L3 and the remainder of the body is supported from L3. Therefore in standing or walking all movement passes through L3 and it is therefore it is most vulnerable to lesion.

The anterior-posterior line, which begins at the anterior foramen magnum and ends at the coccyx, is the foundation of spinal movement. The line crosses D11 and D12 which is the central point of the line. Therefore D11 and D12 are of great importance in lateral curvatures of the spine, postural conditions and of blood circulatory conditions involving the blood supply to the abdomen. Whilst being the strongest vertebra in the column D11 and D12 also have the weakest mechanical rib position as they are floating ribs.

As was mentioned earlier, the posterior-anterior line is a line of pressure (complimentary to the atlas-coccyx line) that begins at the posterior margin of the foramen magnum and splits at L2/L3 to both femoral acetabulae. It crosses rib 2 and D2 and therefore binds the occipito-atlantal joint with them (maintaining the integrity of the neck) and maintains the tension in the trunk and legs.

Some new tension lines – Anterior and Posterior Central Lines:

The anterior-posterior central line follows the same course as the anterior-posterior gravity lines. The anterior-posterior central line is balanced against the 2 posterior-anterior central lines that are drawn from the posterior margin of the posterior margin of the foramen magnum through the centre of the body D4 and on to the centre of femoral pressure on the acetabula. The anterior-posterior crosses posterior-anterior line in front of D4 and therefore form triangles above and below D4 and are associated with rib 3. Therefore, any torsion movements of the trunk tend to focus at the rib 3 and D3 and D4 (see original text for view of triangles).

Therefore, the articulation of the head sits on the base of the upper triangle (the foramen magnum) and is poised on the apex of the triangle (D4). Any alteration in the position of the triangle essentially is the alteration of the head in relation to the trunk and leads to strain at the apex of the triangle creating strain at D4 and rib 3 bilaterally. It is therefore logical to conclude that treatment of problems relating to headaches must include treatment of the base of the occiput and D4.