Brace technology thematic series: the 3D Rigo Chêneau-type brace
© The Author(s). 2017
Received: 12 March 2016
Accepted: 27 February 2017
Published: 16 March 2017
Chêneau and Matthias introduced in 1979 a brace concept inspired in casting. The brace was initially named “CTM” from Chêneau-Toulouse-Münster. The name “CTM” is still popular in France but “Chêneau-type brace” is its common name in the rest of the world. Principles to construct this brace were originally based on anatomical descriptions rather than biomechanics, and its standard is poor.
This paper follows the format of the “Brace technology thematic series.” The Chêneau-type brace has been versioned by many authors. The contribution of the present authors is about to the description of the principles based on biomechanics and a specific classification created to help to standardize the brace design and construction. The classification also correlates with specific exercises (PSSE) according to the Barcelona School, using Schroth principles (BSPTS). This current authors’ version has been named “3D Rigo Chêneau-type brace.” The 3D principles are related to a detorsional mechanism created by forces and counterforces to bring the trunk into the best possible correction: (1) three-point system; (2) regional derotation; (3) sagittal alignment and balance. A custom-made TLS brace (thoracolumbosacral) is built in order to provide highly defined contact areas, which are located, shaped, and oriented in the space to generate the necessary vectors of force to correct in 3D. Expansion areas are also essential for tissue migration, growth, and breathing movements, although body reactions depend basically on how well designed are the contact areas. The brace is open in front and can be considered rigid and dynamic at the same time.
Blueprints for construction of the brace according to the revisited Rigo classification are fully described in this paper.
Different independent teams have published comparable outcomes by using Chêneau-type braces and versions in combination with specific exercises and following a similar scoliosis comprehensive care model. This present version is also supported by scientific results from several independent teams.
KeywordsIdiopathic scoliosis Non-operative treatment Bracing Rigo-Chêneau brace Scoliosis classification
This paper, which is about the author’s custom-made version of the popular Chêneau brace, follows the format for the “Scoliosis brace thematic series.”
The original brace, which was presented for the first time by Dr. Jacques Chêneau (Toulouse) and Prof. Matthias (Münster) around 1979, was initially called the Chêneau-Toulouse-Münster (CTM) brace by French physiatrists. The CTM brace was defined as a custom TLSO brace made from a corrected positive mould from a patient’s negative mould. The correction of the positive mould consisted of a complicated process of removing plaster to build a series of pad areas that coincide with prominent regions of the patient’s body in combination with an even more extensive process of adding plaster to build large expansion spaces that coincide with sunken regions of the patient’s body. The pad areas were located, shaped, and oriented to provide a combined deflection-derotation effect, while the expansions had to provide the necessary room for tissue migration, growth, and breathing movements. Chêneau was inspired by Abbot’s plaster cast. Abbot used this same deflection-derotation principle, putting the patient in the best possible corrective position by pushing the humps and decollapsing the sunken regions of the trunk, keeping the correction with a plaster cast that basically contacted the body on the humps.
The main author (MR) has been intermittently in contact with Jacques Chêneau since 1989 and has been correcting the moulds of patients being treated at the Institut Elena Salvá in Barcelona since 1991. The observed poor standard, with totally different Chêneau-type brace designs for the same curve pattern, was the main impetus behind this author’s proposition of a standardized treatment method in the late 1990s. The standardized treatment method consisted of redefining the theoretical principles, brace construction, and classification. Since 2002, the results of this proposition have been shared with many orthotists, MDs, and PTs during a yearly course offered at the Bundesfaschule für Orthopadie Technik (BUFA) under the name of “Chêneau Korsett nach Rigo,” and have been partially published in two papers [9, 10]. In the next section, the authors describe in detail the theoretical principles of the Chêneau-type brace according to their own interpretation of how the brace should work. Consequently, the following principles would be better called “principles and recommendations from Rigo and Jelačić to construct a Chêneau-type brace or Rigo-Chêneau-type brace.” Classical anatomical descriptions, such as the region map (i.e., pads and expansions) published by Chêneau in the past, shall not be reproduced here. To clarify, some orthotists improperly use the name RSC when building their own Chêneau-type braces following these current principles; it exists in a CAD CAM version—a commercial product with the registered name of Rigo System Chêneau or RSC®—which uses a German company to reproduce braces from a library of original plaster moulds designed by the main author (MR), so the name RSC should not be used by those creating their own custom-made versions of the Rigo-Chêneau-type brace.
The 3D TLSO Rigo-Chêneau-type brace is a corrective device uniquely constructed to bring the trunk and spine into the best possible postural and morphological 3D corrected alignment by using a combination of forces applied to the trunk surface by specifically designed pads, facilitated by expansion or escaping spaces. As such, this is not a full-contact or almost-full-contact plastic, anatomic, and symmetric brace with pads inside to push the humps. All the pads are located, shaped, and oriented in a highly specific manner to push on selected regions of the trunk to bring the patient into the best possible 3D correction, while the remaining areas are not touched by the brace (i.e., areas of expansion or escaping spaces). The corrective reaction of the body depends on the level, shape, and orientation of the pads.
The authors have been following the general principle of correction defined in 1992 by Jean Dubousset during his amazing lecture about the importance of the 3D concept in the treatment of scoliotic deformities . Dubousset defined the scoliotic deformity as “a combination of torsional regions joined by junctions; every torsional region formed by a variable number of vertebrae in anatomical lordosis, rotated and translated to the same side.” In the section about practical considerations on cast and brace treatment, Dubousset remarked that “efforts at reducing a scoliotic curve had to be directed toward reduction of the structural lordosis and application of a detorsional force rather than the previous distraction force.” Thus, by applying a detorsional mechanism, the objective is to achieve maximum derotation with the best possible alignment in the frontal as well as the sagittal planes.
Three-point systems in the frontal plane
Pair-of-force for regional and local derotation
Correct balance and physiological alignment in the sagittal plane
It is important to note that these principles do not work in isolation but rather in combination and, consequently, the isolated description of one principle after the other will always be imperfect. However, to maintain a logical format, the principles are explained separately below.
The observed curve pattern determines the specific design of the pads and expansion spaces. Therefore, it is necessary to use a specific and reliable classification to ensure a good standard. This classification has been described in a previous paper  and will be revisited later in this section.
The pair-of-force system consists of two contrary forces in different directions applied on a somewhat wide section of the trunk at the same level in order to derotate the section (i.e., regional derotation). The pair-of-force system has to apply the highest force at the apical level, where the vertebra is more rotated (i.e., local derotation).
The pair-of-force system also has a special function in the main thoracic region: the correction of structural or anatomical lordosis of the main thoracic curve. This does not refer to the global or regional geometry of the scoliotic spine observed in the lateral projection on the X-ray. The structural or anatomical flat back is related to the torsional phenomena. It has also been defined as relative anterior spinal overgrowth (RASO) [13–23], and although it has been shown to be secondary to the torsion of the spine (Stokes’ vicious cycle modified by Burwell [24, 25]), it could hypothetically be primary . The objective is to achieve the best possible correction of this anatomical lordosis using only the detorsional mechanism while keeping the trunk in a correct sagittal alignment without forward flexion or backward extension. This is the hypothesis of the main author (MR) against the proposal of some colleagues promoting a forced forward flexion applied on the thoracic region in order to correct the flat back. The experience of the author is that, by following this proposal, the anatomical flat back does not attain a better correction, but the proximal and distal regions become more kyphotic. In any case, it must be accepted that, in scoliosis cases with significant potential for progression from a rapid and strong lordotization of the thoracic spine, no matter the design of the brace, the morphological flat back cannot be avoided.
Pelvis section has to be fixed in the frontal plane of reference, with 0° of rotation, or can be mildly over-derotated when it is rotated in the pathological situation. This can be done using a fully closed pelvis section or a partially open pelvis section (i.e., plastic covering one hemi-pelvis). Indications are discussed later in this section (brace design according to curve pattern).
Correct balance and physiological alignment in the sagittal plane
A necessary base for correct trunk balance in the sagittal plane is a neutral pelvis inclination. Pelvis inclination must be in accordance with the individual “pelvic incidence.” A correct sagittal balance depends basically on the relationship between pelvic indexes and the values of the maximum lumbar lordosis and maximum thoracic kyphosis, in absence of any sagittal morphological deformity. Thus, the possibility to achieve a correct sagittal balance and a more or less individualized correct sagittal alignment depends on the amount of morphological lordotization observed in the main thoracic region in relationship with the pelvic incidence. Reaching a correct sagittal balance and alignment is more difficult in cases with higher component of morphological lordotization in any region of the spine.
The classical upper extension on the concave thoracic side can be generally used unless there is a structural proximal curve, primary or secondary to a previous brace treatment. In that case, we recommend applying a specific design called a “D modifier,” where the upper extension works like a derotational pad rather than a counter-rotational pad. The D modifier is similar to the dorsal pad design for the main thoracic curve. The main limitation to treat a structural proximal curve is the theoretical need of a decollapsing effect on the proximal concavity. This can only be achieved by creating a three-point system with the use of a superstructure. The purpose of the superstructure is to provide a proximal counter-pressure applied on the lateral aspect of the neck on the convex thoracic side (main thoracic curve) while applying a compression mechanism for the proximal convexity on the trapezium prominence. Figure 13 has shown the D modifier working with a type of suggested superstructure, but any other design with similar effect could be used. In any case, the use of the superstructure makes the brace more visible and, thus, increases brace-related stress. We recently introduced a technical variation, which consists of an additional full three-point system, still working underarm, but only in case the apex of the proximal curve is T4–5, not T3. Since adolescents do not readily accept the first technical solution, we previously recommended a removable superstructure to be used only at home, enabling patients to experience a social life without the more visible superstructure. The second technical solution is theoretically more acceptable but, in practice, causes more discomfort due to the relatively short distance between points. Obviously, this curve pattern shows an increased risk of brace failure so clinical control should be very careful in these cases and expectations should be realistic.
We describe in this section the brace design and blueprints according to curve pattern.
The brace design is based on the application of the aforementioned principles of correction, according to the different curve patterns. A curve pattern-specific classification was developed based on clinical and radiological criteria. The classification contains most of the curve types that require treatment and has been shown to be reliable . In this paper, the classification has been revisited and, after years of use in a clinical setting, some minor changes have been introduced to facilitate its use.
To use the classification properly, we recommend first examining the patient and then reviewing the radiograph.
Three-curve pattern or A type
Four-curve pattern or B type
Non-3, non-4 or C type
Single lumbar/thoracolumbar or E type
Also radiological criteria have been previously described . This is a short review, introducing few little changes.
Curve pattern compatibility
Transitional point offset
First radiological criterion: curve pattern compatibility
Two relevant changes from the original description:
Second radiological criterion: transitional point (TP) according to the central sacral line (CSL)
Third radiological criterion: L4–L5 counter-tilting
This criterion was also described in the original paper on classification . It is positive when L4 is more tilted than L5 and negative when L4 and L5 are parallel. This criterion is only necessary to confirm B type and, when necessary, to differentiate between B type and C type. B types are associated with a positive L4–L5 counter-tilting. C types are associated with a negative L4–L5 counter-tilting.
E types are like B when describing the lumbosacral region, so it will always show a positive L4–L5 counter-tilting (at least in idiopathic scoliosis).
The “D modifier.”
Any of the above described A, B, or C type could be associated with a primary or secondary (from previous bracing) proximal structural curve.
The brace (blueprints)
Every basic type 3C (A type), 4C (B type), N3N4 (C type), or single lumbar/thoracolumbar (E type) is treated following specific principles that were described in the previous sections. Below is the more specific application of the three-point system principle according to the different types.
Specific designs and construction for “A” types
The function of the three-point system is to bring the trunk into the best possible correction in the frontal plane. For a classical right convex thoracic scoliosis, we need to translate the main thoracic region right to left in between the two caudal (lumbo-pelvic) and cranial (proximal thoracic) regions. A caudal pelvic pad with a strong dorso-lateral lumbar support on the left side, a more proximal main thoracic pad on the right side, and the most cranial pad for the proximal thoracic region on the left side form the main three-point system. When constructing these pads on the positive mould and to achieve the best possible correction, the technician should bring the left proximal pad as high and medial as possible. As described above, the orientation of the main thoracic pad allows it to work from one side and in its lateral component as a part of this main three-point system, while forming part of the dorsal component of the pair-of-force for derotation. The lumbo-pelvic as well as the proximal thoracic regions, including the shoulder girdle, have to be maintained in the best case with no rotation (i.e., the frontal plane of both regions should coincide with the frontal plane of reference). The proximal thoracic region will need a counter-rotation force integrated in the upper pad. In A2 and A3 types, a counter-trochanter pad is necessary on the right side to provide a secondary three-point system, facilitating a better postural balance in the frontal plane. To keep the patient vertical, it is necessary to stretch the soft tissues from the lumbo-pelvic concavity, which are shortened in the axial direction; otherwise, the trunk would bend to the right side due to their tension. In A1 type, the main thoracic pad is larger in the cranio-caudal direction compared with A2 and A3 types and enables the shortened soft tissues from the lumbo-pelvic concavity to be stretched more efficiently with the frontal plane translation obtained from the action of the left lumbo-pelvic pad and the right large thoracic pad, including the upper lumbar, the thoracolumbar, and the main thoracic regions. In this way, the A1-type brace can be constructed without the right counter-trochanter pad and the pelvic area can be opened on the right side.
Specific designs and construction for “B” types
The B-type brace can be built with the pelvis open in most cases, but it may be necessary to use a counter-trochanter pad on the left side (for the example used here of right thoracic/left lumbar or TL). However, the decision about when to use an open pelvis or when to close it to provide the counter-trochanter pad is not based here, as in A type, on the diagnosis of a particular subtype. Both B1 and B2 can be built with a complete pelvis or with an open pelvis. We cannot give an evidence-based explanation about the cause or causes of the frontal plane imbalance in B type scoliosis, so we cannot explain why some patients attain in-brace balance of T1 and TP on the CSL, accepting with no relevant problems the open pelvis design.
Specific designs and construction for “C” types
Specific designs and construction for “E” types
How to prescribe the brace?
It is a more or less generalized rule in this field that different curve patterns require different brace concepts or orthopedic products, which can be prescribed according to the doctor’s specific knowledge, experience, and preferences. However, although a prescription of “Chêneau brace” exists with its own reference code number in the list of orthopedic products covered by the public health system in many countries, this does not guaranty the minimum quality and standard required treating the patient effectively, efficiently, and safely. RSC® has a number, but only in Germany, and cannot be used by custom-made braces and other CAD CAM systems. Thus, the Rigo-Chêneau brace can and must be prescribed under the name “Chêneau brace” according to Rigo principles and classification. However, the so-called Chêneau brace is a “highly specific corrective device” that has to be built not only according to the principles for each curve pattern but also taking into consideration individual factors like the patient’s morphology and correctibility. The whole concept was inspired in the plaster cast technique applied by the old masters, so it is not possible to build a good standard Chêneau brace with repeatability and consistency without specific and deep knowledge of the 3D nature of idiopathic scoliosis and extensive experience with scoliosis correction. A good Chêneau brace can only be constructed and fitted by an experienced medical doctor with specific knowledge of scoliosis correction, assisted by an orthotist, or by a highly educated and experienced orthotist working in full collaboration with a multidisciplinary team coordinated by a medical doctor, who is also highly educated in this technique, and a scoliosis physiotherapist, who provides his/her specific knowledge about the patient’s correction throughout posture and movement. Historically, the contamination by other brace concepts has produced unacceptable failures in the technique.
How to build the brace?
Classical hand-made technique, which is based on the modification or correction of a positive mould of the patient’s trunk from a negative mould taken directly on the patient using plaster bands. Eventually, the positive mould can be reproduced by CAD CAM after a laser capture of the patient’s trunk. The modification of the positive mould consists in shaping all pad areas and expansion spaces according to the desired curve pattern-specific design. It is generally assumed that pad areas are built by removing plaster from the positive, while adding plaster forms the expansion spaces. However, depending on the design, it is common for pad areas to be shaped by adding plaster and for spaces to be created by removing plaster. The brace itself is built by modeling a thermoplastic structure, which is commonly 4 mm of polypropylene-copolymer, on the modified positive mould. The knowledge about how to affix the plastic to the mould is part of the general knowledge of a certified orthotist and is not explained in this paper. The trim lines, however, are essential to the success of the brace and are determined during the fitting process. Improper trim lines can destroy a well-constructed brace. Generally speaking, the plastic is prepared by the orthotist for the first fitting such that all trim lines are slightly higher (on the top) or lower (on the bottom) than necessary for the initial fitting.
Similar to the classical procedure, the CAD CAM system enables the orthotist to laser capture the patient’s trunk and use a software program to modify the virtual mould. The program offers a partially predesigned mould according to the two basic types: 3C and 4C. The authors are not familiar with this procedure and, although many orthotists use this system to build Chêneau-type braces and derivatives, they know of no orthotist who uses it to specifically build a Rigo-Chêneau-type brace.
Using a CAD CAM system from a predesigned library, a fully predesigned mould is selected and modified according to the patient’s specifications, including static as well as dynamic measurements. The library can be based on a somewhat complex and complete set of models and the selection can be based on a somewhat complex and complete classification.
This paper describes the principles that provide a better understanding of how to build a custom brace. CAD CAM procedures are not described herein.
How to check the brace?
In our particular case, the orthotist and MD make the first fitting. First, in case the patient is fitted for the first time (no previous brace treatment), the doctor explains the brace objectives to the patient. Depending on curve flexibility, the patient feels more or less pressure from the pads. The more rigid the curve, the more pressure the patient will note, and the more marked the trunk posture will be changed. From one side, pressure produces physical discomfort and, depending on the patient’s sensitivity, this first contact with the brace can be a determinant for brace acceptance. Alternatively, the change of trunk posture creates a neurological discomfort by changing suddenly, without adaptation, the body schema. As a result, the patient must be managed calmly and respectfully. For the first trials, the orthotist will help the patient put the brace on, but the brace will be closed only with the patient lying in the supine position. Typically, the brace is finished with three straps in the front, but for the fitting phase, two straps are adequate. The two straps are closed gradually until the right side of the plastic overlaps the left side (for a right thoracic curve). The brace has been built such that extra volume will guaranty the life of the brace for at least 10 to 12 months, even in the accelerated growth phase before and during the peak of growth. A well-constructed brace adapted after menarche should usually work until the end of treatment. The brace is fitted alternating the caudal and cranial strap, and once it is finally fixed in the lumbo-pelvic region, we ask the patient to breathe deeply while observing thorax expansion. At a certain point, the patient has to fight against the brace to make a full inspiration. When this happens, we use the exhalation phase to completely fasten the straps to their final position and mark the straps with the “maximum” closing point. In flexible curves, this position is well accepted from the beginning. In rigid curves, fitting the brace at the maximum position can be stressful for the patient, so we settle on a “minimum” fitting point. To find this point, we unfasten the upper strap but keep the brace closed in its maximum position, asking the patient to fully inhale while carefully releasing the strap, finally fastening it in the minimum position, where the patient can achieve full inspiration with practically no resistance from the brace. At this time, we leave the patient in the lying position for a couple of minutes and move away to observe his/her reactions. Then, we help the patient get up and observe how she/he stands at the very first moment. The patient should be able to stand balanced in the frontal as well as in the sagittal plane for a couple of minutes if the brace is well designed. During this time, the orthotist can mark the trim lines, taking care not to cut more than necessary. It is better to cut too little than too much in this first trial. The brace is then prepared for a second trial and the procedure is repeated. In the second trial, the patient is usually able to stay in the upright position longer so the orthotist can spend more time deciding on the position of the final trim lines in both the upright and sitting positions. The orthotist and MD then consider whether the combined pressure points bring the patient into the maximum possible correction in all three planes. Pads should be touching the body at the right points and in the right direction according to the aforementioned principles. One of the most controversial issues is how high the brace should be on the convex thoracic side. There is no clear rule but, generally speaking, in flexible scoliosis the brace can be cut lower, slightly cranial to the apical level of the thoracic curve (warming the plastic and releasing pressure up to the apex, but maintaining some plastic to prevent the brace from being too short when the patient grows). In rigid curves, it is better to leave more plastic cranially. In this case, the maximum pressure goes to the more prominent part of the rib hump and, as long as the curve is not immediately corrected, the upper plastic will not push the ribs, so there is no need to warm and release pressure there. Do not cut the plastic because the plastic will not be visible, and it is always better to have additional plastic cranially to the apex to continue reaching the apex after the patient grows. The counter-pressure point working at the proximal thoracic region has to be totally adapted to the upper ribs, pushing to medial but with a very light dorsal direction to form a pair-of-force for deflection with the main thoracic pad. It should not be possible to bring the patient passively with our hands or actively by asking him/her to bend to the convex thoracic side to a bigger correction. The patient has to be blocked in the maximum possible correction in the frontal plane through these two forces provided by the main thoracic pad and the upper thoracic counter pad. If this correction is not achieved, consideration should be given to increasing the pressure by adding internal pads or cutting the upper counter pad to bring it to a more medial position by using metal extensors (Fig. 58). Sometimes, especially in very flexible curves, the correction is poor enough to consider re-making the brace as the best and most practical option.
The brace action also must be checked at the lumbo-pelvic region. Lumbar support in A and C types has to push on the lumbar convexity from below the apex and just reaching the apex, with no need to go over the apex. This support is, in a way, integrated into the pelvis section. The difference between the lumbar support and the real lumbar pad from B types has been explained above. In B types, it is necessary to check that the pelvis is brought fully to the left (in the example of a right thoracic/left lumbar scoliosis) and maintained by the brace in the frontal plane of reference (with 0° of axial rotation). Cranially, the lumbar region has to be derotated and translated to the right, reaching the maximum possible correction. The anterior design of the brace is essential to achieve this effect. The lumbar pad, which pushes from dorso-lateral to ventro-medial, needs an “escaping” space exactly at the same level in the anterior-lateral part. The body will totally fill this space in the upright position, and abdominal expansion during breathing mechanics will occur mostly laterally and back on the lumbar concavity. The anterior abdominal pad on the right side pushes from ventro-lateral to dorso-medial, exactly in the opposite direction of the lumbar pad, but at a lower level, to prevent any compression or “sandwich effect.” Otherwise, the best correction cannot be reached because the translation between the pelvis and lumbar regions is blocked. The anterior abdominal pad, which works in combination with the lateral pelvic pad, should help to stabilize the pelvis into the best possible 3D correction.
The brace is then finished by the orthotist and MD, who indicate a schedule for adaptation after training the patient/parents to put the brace on and take it off by herself/himself.
Protocols and everyday usage
Full-time: the patient must wear the brace 20–23 h per day
Part-time: the patient must wear the brace 14–16 h per day
Nighttime: the patient wears the brace only at night
Full-time is the most common recommendation for patients with a scoliotic curve over 25° and in the rapid period of growth at Tanner 2–3, Risser 0–2, pre-menarche, or 1 year after menarche (in girls).
Two different schedules for adaptation are indicated to reach full-time, but this aspect is flexible and many variations are made according to individual characteristics. In general, we recommend that the patient first sleep in the brace, then adapt to daytime wearing at home, and finally wearing the brace outside the home.
Historically, one to five trials has been necessary to sleep a full night in the brace. When the patient can wear the brace the entire first night, we recommend a rushed adaptation schedule. When the patient needs more than one night, we recommend a slower adaptation schedule. In the rushed schedule, after the first night, the patient wears the brace at home for 1 h the first day, then doubling the time each day until fully filling all the hours at home. Then she/he can go to the school wearing the brace, reaching full-time in a few days. In the slower schedule, the patient repeats each step one or two times (e.g., wearing the brace for 2 days only at night, then wearing the brace 1 h for 2 days at home, then 2 h for 2 days, 4 h for 2 days, and so on). It can be even slower, repeating daytime during 3 or 4 days. Basically, the schedule depends on the scoliosis rigidity.
One month after reaching full-time, the in-brace correction is checked in a radiograph. To reduce the number of radiographs as much as possible, we check in-brace correction in the AP/PA radiograph, while the sagittal plane alignment is followed out of brace by surface topography.
The brace progress is checked every 3 months during the period of rapid growth, especially before menarche. Clinical control is made every 6 months by measuring anthropometrics, ATI, breathing function, surface topography, clinical photos, self-perception, and HRQL (in our protocol TAPS and SRS-22). We do not repeat a new radiograph every 6 months when patients/parents report good compliance and the clinical picture has improved. No clinical changes or worsening or suspicion of a change in the curve pattern is considered a reason to repeat a radiograph out of brace. At this point, it is not necessary for the patient to remove the brace many hours before the radiograph is taken; 2–4 h is enough. Failure of bracing or a change in the curve pattern necessitates the development of a new strategy.
The life of the brace, on average, is around 1 year during the period between 1 year pre-menarche and half a year post-menarche. One year and a half/2 years before this period, and even longer when the brace is made 6 months after menarche.
When the brace becomes too small due to growth and development, a new brace is indicated when necessary and a new in-brace radiograph is prescribed to check correction. It is not rare to find a loss of correction into the second or third brace, but in our experience the out-of-brace value of the Cobb angle is not far from the in-brace value in those cases. Good responders use to show continued improvement of correction.
The full-time regime is followed by most patients until 2 years after menarche and Risser sign 3 (European)/4 (American). The patient is then recommended to wear the brace part-time. An out-of-brace radiograph is prescribed after 1 month of part-time wear (8 h out of the brace before the radiograph). When values are acceptable, part-time is maintained for 3 to 6 months and the patient then wears the brace only at night for 1 year. Out-of-brace radiographs are repeated 1 month after wearing the brace only at night, as well as 1 month and 1 year after weaning.
Outside of the weaning period, part-time wear is indicated for patients who will not wear the brace outside of the home. These patients are informed about the dose-effect response of bracing and are made aware of the risks for failure.
Nighttime use was formerly recommended in pre-puberal cases with good-to-excellent in-brace correction and rapid improvement of the clinical values. Nighttime bracing often allows us to increase the brace correction, but we follow the same basic principles.
A radiograph every 6 months is recommended when the patient is under the partial or nighttime regime or for full-time non-compliant patients, unless clinical values improve in a relevant way.
Most patients combine bracing with a regular regime of exercises according to the Barcelona Scoliosis Physical Therapy School (BSPTS), which basically follows Schroth’s principles [30, 33]. The patient removes the brace to perform her/his Schroth exercises. In fact, the principles of correction used by the Rigo-Chêneau-type brace come from the evolution of the Schroth principles established by the BSPTS. We do not use to prescribe specific exercises in-brace, but patients can practice physical activities with the brace. It is recommended to remove the brace to participate in-group sports to avoid injuring others (in case of competition).
In spite of its growing popularity, literature about the Chêneau-type brace is limited in comparison with other popular brace concepts. With the exception of some well-designed prospective studies, the methodology of most of the published series is low in quality. It is first necessary to provide some background on the efficacy of brace treatment, in general terms, and related to the initial in-brace correction as a predictive factor of the end result.
Weinstein et al. recently published the results of a multicenter study on the effects of TLSO bracing in adolescents with idiopathic scoliosis, enrolling both a randomized cohort and a preference cohort, concluding that bracing significantly decreased the progression of high-risk curves to the threshold for surgery . The external evidence for bracing, when a TLSO brace is used, strongly supports its effectiveness. Thus, the question is not whether bracing works or not but how to achieve the best possible result in terms of preventing surgery as a main goal, preventing progression as a primary goal, and permanently decreasing the pre-treatment angle as a secondary goal, all while improving the trunk shape and back asymmetry with no significant deterioration of function and, generally speaking, health-related quality of life (HRQL). The Weinstein paper also corroborated, in this case, the highest methodological quality, the previously suspected strong brace dose-response relationship. Previous prospective studies had shown the relationship between the short-term in-brace correction and end result. For whatever reason, in-brace correction is not reported in the Weinstein paper so, unfortunately, this relationship has not been confirmed in this paper. Nevertheless, even admitting its low quality, the existing evidence cannot be ignored.
In one of the classical references on brace treatment published in 1980, Carr et al. suggested that an initial in-brace correction of more than 50% was a predictive factor for a significant and permanent final correction . In this study, however, 133 patients were treated with a Milwaukee brace, and by 1980, it was already known that the Milwaukee brace rarely achieved such a high in-brace correction on a regular basis. In a short series of 62 patients treated with the Milwaukee brace, Heine and Gotze  showed a very poor in-brace correction of less than 10%. In-brace correction as a predictor of the end result was also supported in the study from Noonan et al. , where patients treated with a Milwaukee brace and a progressing curve that required surgery showed a very poor in-brace correction of 8%, while those not needing surgery were initially corrected by the brace with a mean percentage of 20. Surprisingly, in this last series, a good result could still be expected with a poor in-brace correction based on today’s standards.
Later, three papers have stressed the relationship between initial in-brace correction and final outcome. Katz et al.  investigated the factors that could be predictive of the final outcome in patients with large curves treated with the Boston brace. The analyzed factors were Cobb angles, vertebral tilt angles, coronal decompensation, apical vertebral translation, apical vertebral rotation, lateral trunk shift, rib vertebral angle difference, pelvic tilt, and lumbar-pelvic relationship. Katz et al. concluded that patients with a double curve pattern in which the thoracic curve is over 35° Cobb and the lumbar-pelvic relationship is higher than 12° were significantly more likely to show curve progression. They also found that in-brace correction of at least 25% in double curves significantly increased the likelihood of success. Landauer et al.  predicted a final average curve correction of 7° in a child at growth when an in-brace correction of 40% could be reached with a Chêneau-type brace. Finally, Castro  concluded that brace treatment was not recommended in patients whose curves did not correct at least 20% in a TLSO. Most of the papers on braces that can be classified into the TLSO group have reported historically higher in-brace corrections in comparison with the Milwaukee brace, including the Chêneau-type brace.
The Boston brace has been considered the gold standard of the so-called TLSOs. It is definitely the most popular among scoliosis specialists around the world. Thus, it is obligatory for the authors of this paper to justify their gradual withdrawal from the Boston concept in favor of the Chêneau concept. Early studies on the Boston brace have reported about in-brace corrections of 50 to 60% . Later, Uden et al. compared the in-brace correction of the Boston thoracic brace without superstructure (41%) with the Milwaukee brace (10%) . In its already classical paper, Emans et al. also published a “mean better in-brace correction” of 51% . The results of this last study showed that the Boston brace produced better in-brace corrections in single curves with the apex lower than T8, something also observed in other TLSOs. McCollough et al., reporting on the outcomes of the Miami brace, found that the initial correction was 36% in thoracic curves, 56% in thoracolumbar, and 63% in lumbar . Double major curves showed an initial correction of around 37–38% for both curves, lumbar and proximal. At that time, popular opinion indicated that the Milwaukee brace was the choice for thoracic scoliosis with the apex at T8 or higher as well as for double curves with the thoracic apex cranial to T9. Conversely, a preliminary study from Laurnen et al.  showed the higher efficacy of the Boston brace compared with the Milwaukee, even for thoracic scoliosis with the apex at T8 and T7. The authors of this study strongly recommended locating the main thoracic pad pushing on the ribs from above but reaching the apex, in combination with a counter pad extended more cranially to the upper ribs on the concave thoracic side. Jonasson-Rajala et al.  and, later, Périé D et al.  also reported on the importance of the upper extension in order to create a three-point system to more efficiently correct the scoliosis at the main thoracic region. Also in the old study from Emans et al., the result for scoliosis with the apex lower than T7 was similar no matter if it was added to a superstructure or not . The principle of “pushing at the apical level on the convexity of the main thoracic curve,” in combination with other forces, was also supported by Wynarsky and Schultz  and Aubin et al. [48, 49]. Thus, at least these two theoretical biomechanical principles, both present in the original Chêneau concept, eventually found full support in external evidence. However, sometimes theory goes one way and its practical application goes a different one. We still see many Boston braces fitted incorrectly in accordance with this principle, a fact that is clearly detrimental to the efficiency of the Boston concept. Unfortunately, we also see many Chêneau-type braces clearly failing on this principle.
The earliest results with the Chêneau-type brace were published in Germany. Hopf and Heine  report the outcomes of 52 patients treated with a Chêneau-type brace between 1979 and 1980. The mean initial in-brace correction, including single thoracic, single lumbar, and combined curves, was 41%. Weiss and Deez-Kraus  reported an initial in-brace correction of 39% for the main thoracic curve and 58% for the lumbar curve. Rigo et al.  presented a preliminary mean in-brace correction of 34%. Finally, Liljenqvist et al.  achieved a mean in-brace correction of 36%. In a further study, Rigo et al.  showed a mean in-brace correction of 31% for the major angle and 26% for the secondary angle, and also reported an initial in-brace axial rotation correction of 22% for the major angle.
Comparing the in-brace correction of this series with those related to the Boston brace, a logical question would be: why continue using this theoretically more complex concept when the Boston concept offered an existing good-to-excellent in-brace correction with the added benefit of a theoretically better standard?
First, it would be a mistake to consider external evidence in only one sense—the in-brace correction of the Cobb angle—when the series are hardly comparable. In-brace correction depends on many factors; some related to the brace but others related to the patient. Flexibility is one of, if not the most important, factors. Weiss has discussed his experience with an 11-year-old girl treated with one of his versions of the Chêneau-type brace, the Chêneau light® brace . With a Cobb angle of 38° at the start of treatment, she was over-corrected and, after 2 years, had a Cobb angle of 19° with part-time bracing (16 h), which was sufficient to halt further progression. Thus, theoretically, any significant difference when comparing in-brace correction from two different studies could be due to both brace quality and patient quality. The ideal way to make studies comparable would be to match age, gender, and initial Cobb angle as well as curve pattern distribution and flexibility in each determined curve pattern. Thus, in-brace correction as an indicator in comparing brace quality between two different or similar brace concepts should only be partially considered, unless the methodology is strictly comparable.
On the other hand, when considering the discussion above, a significant increase of the in-brace correction reported by the same team over two different periods of time could be considered a good indicator of improved brace quality during the “learning curve” process after transitioning from one brace concept to a different one. Maruyama reported the outcomes of a first series of patients treated with a Rigo-Chêneau brace. His in-brace correction was similar to the first series reported by other authors in their preliminary series . However, the pioneers of the Chêneau brace concepts have gradually increased the percentage of in-brace correction, suggesting that the correction and subsequent improved end results could be due to enhanced brace quality gained from clinical experience. We recently compared the in-brace correction of our own handmade braces (positive moulds corrected personally by the main author MR) with those from a CAD CAM system producing braces from models included in a library of pre-corrected moulds . In this study, a group of 27 patients (26 female) with a mean age of 11.8 years (±2.1), Risser sign of 0.2 (±0.6), and an initial Cobb angle in the major curve of 33° (±7.2), all with no previous treatment and treated with a handmade brace, was compared with a matched group of 41 patients (39 female) treated with the CAD CAM system. In-brace correction—53% in the handmade group and 52.6% in the CAD CAM group—was not significantly different for the major curve. However, 53% is significantly higher than our first in-brace correction of 34% reported in 1995. The in-brace correction achieved with the CAD CAM version has been independently reported as 43, 42, 48, and 37% for thoracic, lumbar, major, and minor curves, respectively, in a group of 147 patients; a sub-group of patients fulfilling the more restrictive SOSORT criteria reportedly achieved corrections of 54, 59, 61, and 52% for thoracic, lumbar, major, and minor curves, respectively . Notwithstanding, as discussed previously, the Chêneau-type brace is not just an orthopedic product but also a brace concept that is permanently evolving in pursuit of the highest possible standard. Brace design can suffer relevant changes and still be respectful to the original concept and theoretical principles. We presented a study comparing two different designs to treat the A1 curve type . The A1 curve type is characterized by a long thoracic curve extending into the lumbar region, with a low apex in the main thoracic region (T9–T11). The study concluded that an over-corrected translation between the pelvis, including the coupled low lumbar region, and the main thoracic region significantly increased the correction when compared to the previously used classical design. The classic brace was built with a fully closed pelvic section, while the modern brace leaves one side totally open. A comparison of the in-brace correction in two similar groups of patients diagnosed with this A1 curve pattern showed a highly significant increase in-brace correction treated with the modern design in comparison with the group treated with the classic design (76.6 versus 45.3%, p < .001).
With this perspective, the fact that our own reported initial in-brace correction was not reaching 50% did not force us to give up. The main reason that we changed from the standard concepts used in Spain (Milwaukee, Boston, and Lyon) to the Chêneau concept around 1989 was the observed correlation between the use of the standard braces and the thoracic and lumbar morphological and functional flat back syndrome. Knowledge about the 3D nature of idiopathic scoliosis and its application in scoliosis treatment became very popular among scoliosis surgeons at that time. Jean Dubousset, in his already classic lecture entitled “Importance of the three-dimensional concept in the treatment of scoliotic deformities” (at the Montreal International Symposium on 3D Scoliotic Deformities joined with the VIIth International Symposium on Spinal Deformity and Surface Topography), pointed out the cause-effect relationship between the use of the Milwaukee, Boston, and Lyon braces and flat back syndrome . This relationship has been confirmed and reported primarily by populations treated with the Boston brace [48, 49, 60–62], but this undesirable effect is also produced by other brace concepts, including the Chêneau-type brace. However, according to Dubousset, the only braces in use at the beginning of the 1990s that had the potential to correct scoliosis in 3D were the 3D brace from Graf and Dauny and the Chêneau brace. All these combined arguments, external evidence, and preferences of some relevant clinicians reinforced our attraction to the Chêneau-type brace and forced us to gradually abandon other brace concepts. However, as discussed previously, the standard of the Chêneau-type brace is poor and, in spite of the claim made by the first promoters, the potential to correct in 3D has been studied rarely. Three-dimensional correction makes reference to (1) frontal plane component, the lateral curvature as measured by the Cobb angle; (2) transversal plane component, the axial rotation of the apical vertebrae, as measured by different methods; and (3) sagittal plane component, related to a highly variable amount of altered spinal geometries impossible to measure with a single angle, which “should be decreased or increased.” In other words, in a progressive scoliosis, the torsional phenomenon gradually increases the lateral translation in the frontal plane, with the consequent increase of the Cobb angle; it also gradually increases the axial rotation, no matter which angle might be measured. Thus, reducing those angles is a direct action of the brace correction that can be easily assessed. However, in the sagittal plane, there is no single angle in the lateral radiograph to be decreased or increased always in the same direction for all the cases, which could be used to show the capability of the brace to correct in this plane. Sagittal parameters can be individually assessed according to pelvic incidence; sagittal values will need to be decreased in some cases and increased in others but this should be taken in consideration when designing studies. When we talk about a correction of the flat back component, what are we talking about? Morphological as well as geometrical lordotization of the main thoracic spine most likely happens in most cases of thoracic scoliosis; however, in a variable way and, depending on the orientation of the “plane of maximum deformity,” it is only sometimes visible in the lateral radiograph. The “paradoxical kypho-scoliosis,” a hyper-rotated lordo-scoliosis with a paradoxical kyphotic geometry in the lateral radiograph, although most typically related to severe “early onset scoliosis,” is also observed in adolescent idiopathic scoliosis (AIS) with a relatively mild Cobb angle and a very low morphological lordotic component. Also this should be taken in consideration when designing studies.
Very few studies report on the in-brace correction of the axial rotation. We showed an initial in-brace correction of the axial rotation in the major curve of 22% . Later, in the comparison study of two brace designs—classical and open pelvis—to treat A1 type, the percentage of correction or the axial rotation (Perdriolle) was 29% for the classical design and 59% for the new open pelvis design .
The general claim about the Chêneau-type brace correcting flat back syndrome is not adequately supported by external evidence of quality. Cahuzac JP et al. presented outcomes in 161 patients treated with a Chêneau-Toulouse-Münster (CTM) brace. In this study, 55% of patients were pre-pubertal at the initiation of treatment and the initial main Cobb angle of 27.5° was reduced to 22.5° at the end of treatment, with 70% of the patients stabilized or improved, and 30% showing some progression . The sagittal angle between T4 and T12 decreased during the treatment and returned to the initial value at the end of treatment, concluding that the “thoracic lordosis” was temporary modified by the brace. However, these results are hardly interpretable according to the previous discussion related to the sagittal regional or sub-regional values. Other studies have shown also the tendency to reduce the kyphotic angle at the main thoracic region [64–66]. However, the Chêneau-type brace design used in these studies could be significantly different to the design described in this current paper. As mentioned previously, the pelvic section of the brace is not built in retroversion, as defined in old brace concepts and seen in some Chêneau versions, but maintains a physiological anterior inclination. The Milwaukee concept, as well as the first-generation Boston brace, was based on the popular principle of “obliteration of the sagittal postural curvatures to achieve a better correction of the pathological lateral deviation.” A better understanding of the 3D nature of idiopathic scoliosis proved this principle incorrect, as it has been associated, in many cases, with an undesirable secondary flat back effect, in both the lumbar and thoracic regions . Pelvis retroversion was considered the first step in the application of this principle due to its delordosant effect on the lumbar spine. Abdominal ventral pressure to ensure the delordosant effect was also very popular among orthotists. Soon after the introduction of the first-generation Boston brace, Willner [60, 61] emphasized the importance of reduction of the lumbar lordosis in the correction of the lumbar scoliosis. J. Chêneau was very critical of this very popular principle, recommending from the very beginning against unselective abdominal pressure and pelvis retroversion, but many orthotists used it in the past and continue to use it when constructing their braces under the name of Chêneau. Later, in a study of the 3D immediate effect of the Boston brace on the scoliotic lumbar spine, Labelle et al.  showed that the brace produced a distraction of the lumbar spine similar to that produced by the Harrington instrumentation by correcting the frontal plane deformity at expenses of a significant reduction of the physiological lumbar lordosis. They were not able to demonstrate any significant effect on rotation of the apical vertebra or “detorsion.” Modern Boston brace has abandoned the principle of pelvis retroversion and delordosis but still uses the unselective abdominal pressure. We must admit that at the current state of the art of the Chêneau-type brace, the principle of constructing the pelvis section with a physiological anterior inclination of the pelvis and physiological lumbar sagittal profile with selective abdominal expansion-pressure is subjective but not based on objective assessment. Notwithstanding, the concept of physiological pelvis anterior inclination is not a general one but has a high individual variability. Pelvis indexes (pelvic incidence; sacral slope, and pelvic tilt), in relationship with the sagittal geometry of the spine, more or less recoverable in the brace depending on the lordotic morphological component, could be used as a guide to define the amount of inclination the pelvic section of the brace should have case by case. We are now developing on this issue but cannot offer any information yet aside of the already explained three versions according to a normal, high, or low individual pelvic incidence.
Thus, the question about whether using Chêneau principles in brace construction can prevent the flat back or not is still open. In a relatively old study, we analyzed the 3D geometry of the spine in a group of patients treated with the first version of the Chêneau-type brace  and, although a significant number of patients showed improved sagittal alignment during brace treatment, some patients had what could be considered deterioration of the sagittal profile. From this experience, some significant changes were introduced in the brace design to prevent deterioration and further clinical observation supported the idea that a well-designed brace can prevent the deterioration of the morphological lordotization of the thoracic spine; further studies are necessary to support this statement. A recent study from Lebel et al. , comparing 3D effect from classical TLSO and Chêneau-type brace, has shown that only the Chêneau-type brace is able to reduce rotation of the apical vertebra. Coronal and sagittal correction did not differ significantly when comparing both brace concepts. The authors used EOS technology for spinal 3D reconstruction, but again here, we have no idea about which type of sagittal design they applied to their Chêneau-type version.
Although the end results were reported in some of the old series , more recent series support the effectiveness of the Chêneau-type brace when similar standards are observed. In 2003, two papers from independent centers with similar protocols in conservative management combining the Chêneau-type brace and Schroth scoliosis-specific exercises showed comparable effectiveness in preventing surgery. In a retrospective study, which included 343 patients (females only) with a mean Cobb angle of 33.4° treated with a Chêneau-type brace between 1993 and 1996, Weiss et al. found that only 12% of all patients underwent surgery . All the patients were at least 15 years of age at the time they were last investigated. In the second study, Rigo et al. retrospectively analyzed the outcome in patients treated with a Rigo-Chêneau-type brace . The objective was to determine whether a center with an active policy of conservative management had a lower prevalence of surgery compared with a center that had a non-intervention policy. The study included 106 braced patients who were at least 15 years of age at last review. Ultimately, only 14% (in a worst case analysis of all the intents to treat, including non-compliance and considering lost patients as failures) of braced patients underwent spinal fusion, which was statistically significantly lower than the 28% reported by the center with the policy of non-intervention.
Later, Weiss HR et al.  compared two brace concepts: the Chêneau-type brace (at that time, according to Rigo-Chêneau principles) and the soft brace concept, SpineCor. They compared the survival rates of the two different brace concepts with respect to curve progression and duration of treatment during pubertal growth spurt in two cohorts of patients. All girls in the study were pre-menarchial with the first clinical signs of maturation (Tanner 1–3). Twelve girls with an initial mean Cobb angle of 21.3° were treated with the SpineCor, compared to 15 girls matched in age with an initial mean Cobb angle of 33.7°. During the pubertal growth spurt, most of the patients (11 out of 12) with the SpineCor progressed clinically and radiologically. Progression was halted after the patients transitioned from the SpineCor to the Chêneau-type brace in seven of the progressive cases. The sample treated initially with the Chêneau-type brace showed no progression. After 24 months of treatment time, 73% of the patients with a Chêneau-type brace and 33% of the patients with the SpineCor were still under treatment with their original brace concepts. After 42 months of treatment, 80% of the patients with the Chêneau-type brace and 8% of the patients with the SpineCor survived with respect to curvature progression.
Cinnella et al.  presented at the SOSORT meeting in Lyon a retrospective series of 152 patients treated with a Chêneau-type brace, with a minimum of 20 months of follow-up (mean 56 months). At the end of treatment, the authors observed an average initial curve improvement of 23.3%. At follow-up, they observed an average improvement of 15% from the beginning of treatment. In this study, however, the protocol was different to further published series because 79% of the population was previously treated with a cast. Thus, we are not adding this to the rest of the series discussed in the paper.
Zaborovska-Sapeta et al.  conducted a prospective observational study according to SOSORT and SRS recommendations. The study included 79 patients with initial Cobb angles between 20° and 45°, no previous treatment, Risser 4 or higher at final evaluation, and a minimum 1-year follow-up after weaning from the brace. Results showed that 25% of all patients improved, 23% were stable, 39% progressed below 50°, and 13% progressed beyond 50°. This study suggested that conservative treatment with the Chêneau-type brace and physiotherapy (again, with similar brace standards and similar treatment approaches) can change the natural history of scoliosis, as 48% of patients did not progress.
Another retrospective cohort study from Ovadia et al.  was preformed to identify factors that could predict the therapeutic success or failure of the Rigo-Chêneau brace. Ninety-three patients with an average age of 13 years, Cobb angle of 32°, and Risser 1 were followed. All patients were treated with a Rigo-Chêneau-type brace during a mean treatment period of 36 months, and all had a 2-year follow-up after the termination of brace treatment. The authors concluded that the treatment was successful in 84% of patients, which indicates that the brace provides excellent clinical results in the treatment of mild to moderate AIS. Patients also showed a significant reduction of the angle of trunk rotation, suggesting the ability of the brace to correct the 3D trunk deformity, confirming initial observations about clinical improvement [68, 76]. Correction of the 3D trunk deformity can be assessed by using surface topography  as well as radiological indexes like the rib index from Grivas , although this last has not been used yet in patients treated with a Chêneau-type brace.
More recently, Rivett et al.  analyzed the effect of compliance to a Rigo System Chêneau brace and a specific exercise program on idiopathic scoliosis curvature, and compared the quality of life (QoL) and psychological traits of compliant and non-compliant subjects. Fifty-one subjects, all girls aged 12–16, with Cobb angles 20–50° participated in the study. Subjects were divided into two groups, according to their compliance, at the end of the study. The compliant group wore the brace 20 or more hours a day and exercised three or more times per week. The non-compliant group wore the brace less than 20 h a day and exercised less than three times per week. Cobb angle, vertebral rotation, Scoliometer reading, peak flow, QoL, and personality traits were compared between groups. The compliant group wore the brace 21.5 h per day and exercised four times a week, and significantly improved in all the measures compared to the non-compliant subjects, who wore the brace 12 h per day, exercised 1.7 times per week and significantly deteriorated (p < .0001). The major Cobb angle in the compliant group improved 10.19° (±5.5) and deteriorated 5.52° (±4.3) in the non-compliant group. Compliant group had a significantly better QoL than the non-compliant subjects. The compliant subjects were significantly more emotionally mature, stable, and realistic than the non-compliant group (p < .05). The conclusion of this study was that good compliance of the RSC brace and a specific exercise regime resulted in a significant improvement in curvature, while poor compliance resulted in progression. A poorer QoL in the non-compliant group possibly was caused by personality traits of the group, being more emotionally immature and unstable. Other aspects of QoL like function have not been studied. Based on the theoretical principles of this brace, users claim about no deterioration of breathing function, but we do not know any study supporting this.
As discussed previously, different brace concepts cannot fairly be compared to current state-of-the-art concepts. Thus, the old statement about the best brace being managed with the highest experience by a particular multidisciplinary team could still be defended, at least in terms of patient safety. However, once the efficacy of bracing has been strongly supported, further studies are necessary to demonstrate the ability of a particular brace concept to correct scoliosis in 3D and whether or not 3D in-brace correction is a factor when predicting the success of bracing.
The theoretical disadvantage of the Chêneau-type concept of bracing is the complexity of its principles and fabrication, which has been associated with poor standards. By summarizing previously reported studies and providing supporting published data, this paper attempts to raise awareness and education to improve the future standard of the Chêneau concept. Nevertheless, the fact that consistent and comparable results are reported by at least five independent centers using similar standards cannot be ignored.
Case reports 1
Case reports 2
Case reports 3
Case reports 4
The Chêneau-type brace according to Rigo principles and classification is a 3D corrective device able to provide excellent in-brace correction as well as radiological and cosmetic end results. This paper offers a vast description of the applied corrective principles as well as a short revision of the specific classification, with the ambitious objective of improving the observed poor standard of the classically called Chêneau brace.
Barcelona Scoliosis Physical Therapy School
Bundesfaschule für Orthopadie Technik
Central sacral line
Health-related quality of life
Physiotherapy scoliosis-specific exercises
Relative anterior spinal overgrowth
International Society on Orthopaedic and Rehabilitation Treatment
The authors are thankful to Luke Stikeleather for copyediting the final paper.
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Availability of data and materials
Data will not be shared. This paper is about description of corrective principles and brace design specifications according to specific curve pattern. There is no data, including new software, databases, or relevant raw data to be shared.
MR is the main author of this paper and has contributed in the conception and design of it. To him belongs the intellectual property of the bracing concept as described in this paper. He has been fully involved in drafting the manuscript, preparing figures and case reports 1, 2, and 3. MJ is the second author of this paper and has contributed in the conception and design of it. She has been fully involved in drafting the manuscript and case reports 4. Both authors read and approved the final manuscript.
Manuel Rigo declares the next “Competing Interests”:
1) Medical director of Rigo Quera Salvá S.L.P., a private institution for non-operative treatment of spinal deformities, which can be indirectly benefited by the publication of this paper.
2) Medical advisor of Ortholutions oHG (Rosenheim Germany) and Align Clinic (San Mateo, CA, USA), receiving consultation fees.
3) Lecturer in a course about Chêneau principles during the last 12 years, at the BUFA-Dortmund (Germany).
Mina Jelačić declares no competing interests.
Consent for publication
Written informed consent was obtained from the patients for publication of these case reports and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal.
Ethics approval and consent to participate
This paper describes a personal version of a brace type, which is accepted and used in Spain and other countries. It does not contain any experiment or trial and does not need approval from any ethics committee.
Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
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