Current Theory

How do physiological bone loss and osteoporosis occur?

A cell theory is currently being proposed to explain the mechanisms of these two phenomena. Bone cannot use the same mechanism as the skin, which is continuously eliminated and renewed by the production of new skin. It is assumed that bone is destroyed and rebuilt in situ in small amounts at a time.

Cells destroy small quantities which are reconstructed in situ by other cells. In short, workers destroy part of a wall which other workers then rebuild. The entire wall is not destroyed all at once. Part of the façade is renovated – the oldest part – so that the wall is continuously renewed. This is true for a certain period of adult life.

However, we explained above that the TBV and BMD were at their highest at the end of skeletal growth, starting to fall thereafter. The wall is still new but gradually starts to diminish. To state this more clearly, we should say that the wall shrinks in both height and thickness.

In other words, the workers who destroy the wall are working harder than those rebuilding it. There are several hypotheses: the workers destroying the wall either work more than 35 hours a week or work harder or faster or there are more of them than those rebuilding it.

How can we discover which is the right hypothesis? Theoretically this may seem difficult if not impossible, but this is not the case. In the body there is only one known mechanism which races. This is the mechanism which produces the uric acid responsible for painful episodes of gout.
Whether the destroyers work better or faster does not change any basic factors because we know that bone disappears over the years. The only important point is bone loss.

The hypothesis that there is a reduction in activity of the workers who rebuild the wall – either because there are fewer of them or because they work more slowly – is an admission of impotence – both scientific and philosophic. We shall return to this subject.

Let's try to work out why the workers rebuilding the wall are fewer or less efficient:

- Let's start with efficiency: A trivial explanation is that it's easier to knock down than to build. This is true in that the workers destroying the wall use extremely active acid-based products. They only have to attack the mortar which holds the bricks together and the wall collapses. One single operation.

- The workers who are rebuilding the wall have to stack the bricks and then assemble them with mortar. Two operations. This is both longer and more tiring.

Let's look at the second hypothesis: Why would the two "classes" of workers be different? A newborn baby has the same reserve of blood cells as an adult or an elderly man. On the other hand, we know that, from the age of eight we begin to lose brain cells. However, unlike bone which is renewed, nerve cells which are destroyed are not regenerated. The total reserve is available at birth. We also know that cartilaginous cells start to disappear from the age of 12. They are not regenerated for the same reason as the nerve cells.
No matter what the reason, we note that the wall gradually collapses over time. This brings us back to the philosophical approach: can we stop the advance of time?

If it is the destructive workers who are winning, no matter what the reason, it is logical to fire them. The remaining workers will work at the same rate but the wall will be destroyed more slowly, reconstruction remaining the same.
This is an attractive hypothesis. It is still an admission of impotence however, for two reasons:
- Not knowing how to renew the positive aspect of force, we attempt to neutralise the negative aspect.
- The second aspect, probably the most important, is that this technique has its own limits, forerunner of its own destruction.

Let's go back to the example of the wall and workers. What do we need to build a wall? We need bricks and mortar. The material and workers have to be transported to the site. There is no site hut on a bone. We must therefore use a means of transport. We need rails and railway wagons.

We have seen above that the rails – vessels – are attached to the bone itself. The network is highly developed because you need a gap of 12µ between each rail to "feed" a tissue properly – i.e. bring in the workers (cells) and materials (sugar, fats, proteins, oxygen and mineral salts). How can these be carried when the rails have disappeared and the line is cut? How can you find a wall when the whole building has collapsed?

This leads us to another point. What happens to the cell theory when, for the same reasons that rebuilding is impossible, the workers destroying it cannot be brought to the site? Because bone destruction continues throughout life.
It must therefore continue either through the intervention of the Holy Spirit or by another mechanism. Let's leave the spirit out of it and remain practical. We have seen that blood flows into destroyed bone and blood clots form. What do these clots contain and what happens to them?

see following article
Yves Cirotteau. Modifications morphologiques de la métaphyse fémorale supérieure
chez l'homme atteint de la maladie ostéoporotique.
(Morphological changes in the superior femoral metaphysis in osteoporotic patients)
C.R. Acad. Sci. Paris, Sciences de la vie/Life Science. 1999 ; 322 ; n°5 : 401-411

A certain number of facts are known:

- The cell theory is possible from the start of bone loss. This phenomenon is thought to start very early, from the end of bone maturity at the sites explored.

- It is still possible as long as the vessels are functional, forming a network covering the bone lamellae that they destroy and rebuild by depositing cells. You must bear in mind that the bone reserve is diminished progressively in men and bone loss decreases suddenly in women at the menopause.

- It is inadequate from the moment bone lamella fractures, formation of "holes" inside the bone, interrupt vascularisation and prevent cells from being carried to the site.

- It is obvious that consequently taking oral medication, at this stage of bone destruction, is totally useless.

- It is also obvious that only local provision – inside the bone – of a material with all the characteristics of a biological material, with all the guarantees of tolerance for the human body, is the logical and only solution. No other way of filling the "holes" in bone linked to osteoporosis can be considered, let alone treating the huge losses of bone linked to the compression of spongy bone after a fall.