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A comparison of the Chêneau and Sforzesco braces

Unfortunately, it has become common to think of braces in the same way as we do drugs. But before we go any further, we need to make one thing clear: whereas we all know that aspirin is not the same as paracetamol, in the case of a brace, the name doesn’t really mean anything specific.
A brace is a product that is made-to-measure for the individual patient, and therefore the success of bracing treatment depends not on the name of the brace, but on how correctly it has been constructed for the particular patient. If the pads are incorrectly positioned, or if the brace is constructed so that it sits too low or presses too much on one side, it may even contribute to worsening rather than improving the scoliosis. 

The names of the different braces, therefore, are meaningful only to those who prescribe them. 

Finally, adding to the confusion, Dr Chêneau gave his name to two completely different types of brace: the first Chêneau is much more symmetrical than the second one, which, on the other hand, is clearly asymmetrical. Although the second Chêneau brace is the one most commonly used worldwide, we prefer to use the first one, for two reasons: first of all, it is discreet (practically invisible under clothes) and second, in constructing it, we are able to apply the same principles that characterise the Sforzesco, which is the brace developed at our own centre. For this reason, the Chêneau that we use at Isico has been given a new name: we call it the Sibilla- Chêneau, in honour of Dr Sibilla, a pioneer of our school.

So, how do the Sibilla-Chêneau and the Sforzesco differ? They differ in several features, which determine the choice of one over the other on a case-by-case basis. The decision to prescribe one type of brace rather than another must always be taken by a medical specialist.

Let’s start with the material: the Sibilla-Chêneau, used at Isico, is of monovalve construction and it is made of polyethylene, whereas the Sforzesco has two valves and is made from a much more rigid material. Its two parts are linked to posterior fasteners, and there is sometimes an aluminium rod at the back, too. Being more rigid, the Sforzesco has shown the same efficacy as the old system of plaster casting, but with the huge advantage of being removable for bathing/showering.

The Sibilla-Chêneau tends to be used to treat milder cases with less rigid scoliotic curves; it is also preferred for pre-pubertal patients. The Sforzesco, on the other hand, is used for more severe scoliosis with more rigid curves (for example, in youngsters with greater bone maturation). 

In some cases, patients start off with a Sibilla-Chêneau brace but subsequently switch to a Sforzesco one if the scoliosis becomes too aggressive (a decision reflecting the concept that the treatment should evolve gradually): on a hypothetical treatment scale, we can say that the Sforzesco (a super-rigid brace) is one step up from the Sibilla-Chêneau (a rigid brace).

At Isico, both these braces are prepared in accordance with the SPoRT (Symmetrical, Patient-oriented, Rigid, Three-dimensional) concept of bracing.

 “Symmetrical” means that the brace, externally, appears almost perfectly symmetrical, which makes it unobtrusive and helps to replicate the natural shape of the human body. In other words, for aesthetic reasons, it is outwardly symmetrical. By contrast, internally the brace acts asymmetrically, exerting a three-dimensional corrective action on the deformity. 

The brace is defined “Patient-oriented” on account of its wearability, and therefore tolerability. Being very closely fitting, it moves with the patient, and it does not restrict arm and leg movements at all. Furthermore, since it is easy to conceal, patients accept it readily, rather than merely putting up with it.

The term “Rigid” refers to the type of material used.

Finally, “Three-dimensional” refers to the corrective action of this type of brace on the spine; technically speaking, the brace pushes in a down-up direction; overall, the transmission of the corrective forces to the spine is carefully balanced in such a way as to obtain optimal correction in all three planes of space, without any of the three being allowed to dominate.

As explained at the start, another type of Chêneau brace is also used worldwide; in Italy, we call this the Chêneau 2000: it is an asymmetrical brace that uses expansion chambers. It remains clearly asymmetrical, even externally.  We, on the other hand, prefer to use the symmetrical version of the Chêneau, in order to respect the SPoRT concept mentioned above and also because it favours compliance. Indeed, applying our school of thought, we have obtained, in our patients, the best bracing results recorded anywhere in the world, and this is thanks, in part, to the type of braces we use. Naturally, braces only work if patients actually wear them, and the easier they are to conceal under clothes, the more patients will wear them.

Sforzesco in-brace corrections visible with EOS images

The aim of our study “The three-dimensional analysis of the Sforzesco brace correction ”, published by Scoliosis and Spinal Disorders, is to analyse the Sforzesco Brace correction, through all the parameters provided by Eos 3D imaging system. This is a cross-sectional study from a prospective database started in March 2003.
The study took into account 16 AIS girls (mean age 14.01) in Sforzesco brace treatment, with EOS x-rays, at start, in brace after one month and out of brace after the first four months of treatment
One of the major revolutions in the field of adolescent idiopathic scoliosis during the past 10 years is the development of 3D imaging devices in standing position, such as EOS Imaging – explains dr. Sabrina Donzelli, physiatrist of Isico and one of the authors of the study –  Through the 3D reconstructions produced by dedicated user-friendly software, it is possible to calculate and visualise a series of regional and local parameters characterising the spinal deformity. This new technology allows the clinician to deepen the direct effect of braces in all three spatial planes”.
Brace efficacy can play a role in determining the final outcome of a treatment. In recent years, braces have become really three dimensional, adding a detorsion action and addressing the whole shape of the trunk and its deformity. 
Different braces can act in different ways and may act in one plane more than in the other. Therefore, personalised prescription of the brace can optimise treatment.
According to the results, the Sforzesco brace has its strongest influence on the middle of the spine in the axial plane, while the Torsion Index cannot be considered an index of brace correction.
The three-dimensional elongation effect, which is typical of the Sforzesco brace, can be responsible for the main effect focused on the middle part of the spine and seen in the axial plane.
The main limitation of this study is a very small sample size, associated with a large heterogeneity of data which threaten the internal validity of the study. The lack of distinction in curve types, magnitude, bone maturity and age is a threaten for the external validity too, but “of course this preliminary study gives some interesting insight into the mechanism of the Sforzesco brace action and it suggests that EOS imaging could be very useful also to improve the immediate in-brace correction“.