Lewit Karel: Functional approach and functional thinking

There is a large number of painful afflictions of the locomotive system which lack a clear pathological diagnosis and are therefore described as “idiopathic”. Yet the clinical finding is often very strong – the cause is not given by structural changes but by defects in function. Because of the fundamental difference between the two, as far as the etiological and therapeutical approach is concerned, we must make a definitive choice: is the disease mainly structural or functional? What are the differences and the consequences?

Function (F) is as real as is Structure (S). S can be localised precisely, F tends to form chains of functional defects; however, with S there are often other important differences with F as well. Clinical findings correlate more closely with F than with S; indeed, changes in S can be clinically irrelevant.

In diagnosis, for S we should aim at localisation and the underlying reason for change; with F we should uncover the chain of dysfunction – function is the sum of interactions of several effects. The cause of pain in S lies in the pathological process, while in F it is the tension that usually occurs as a consequence of dysfunction, for various reasons.

The therapeutical aim in S is the healing or removal of the substrate, while for F it is the normalisation of the relevant element in the chain; we therefore use the same treatment for S until healing is complete, but in F we try to treat element after element in the chain.This is why treating F is more complicated, and why we can compare S with hardware and F with software. Never treat in the place of pain! F is always reversible, which allows for immediate, “miraculous” effects. In S, the psychological factor is important, while in F it is part of the functional chain: the locomotor system is the effector of the psyche!

Modern technology is extremely important for S, but hardly at all for F. The relation of cause and effect is transparent for S, but can be inversed for F. Statistical methods are usefully applicable to S, but extremely difficult for F.

Česká revmatologie. 1995, roč. 3, č. 4, s. 190. ISSN: 1210- 7905