**2.2. Breathomechanics**

These high and low targets for in-brace corrections depend on several factors, including the Rigo classification brace type, curve pattern, skeletal maturity, flexibility, and the structural component of the scoliosis, which limits correctability. This last factor is particularly important to the effectiveness of the Rigo Chêneau brace which is supposed to work through the

**Figure 4.** In-brace correction of the Cobb angle has been the gold standard for the measurement of successful bracing. This patient's curvature was reduced from pre-brace 21° Cobb angle to an in-brace Cobb angle of less than 5° in a Rigo Chêneau type brace. The pre-brace X-ray shows the pelvis translated to the left and the trunk to the right. The in-brace

**2.** Three-point pressure systems for the best possible alignment and balance in the frontal plane

The expansion is noticeable and the volume depends on the body morphology. Expansion areas or rooms are not just to be there to be filled at the time but to define the orientation and shape of the contacts. An essential function of the brace design is to produce the right body

detorsional forces and the amount of the mechanical torsion.

X-ray shows the pelvis corrected to the right and the trunk balance to the left.

174 Innovations in Spinal Deformities and Postural Disorders

**1.** Regional and local derotation in the transverse plane.

reaction during breathing (**Figures 6** and **7**).

**3.** The best possible alignment and balance in the sagittal plane.

**4.** Reactive breathing mechanics to restore physiological thoracic kyphosis.

3D correction is defined.

(See **Figure 6**).

The sagittal diameter increases during rotation, bringing the spine out, rounding the back, thus improving the morphological flatback.

The two forces need to be at the same transversal level to be effective. Ventral and dorsal prominences are for different transversal levels. Pushing on them is not enough to get correction.

The intention is to produce a better physiological shape, where the physiological shape in the sagittal plane is more or less pronounced, depending on the pelvic structure (i.e. the pelvic incidence) (**Figure 9**). The normalization of the sagittal configuration of the spine is not possible in most cases due to structural lordotization, and any kyphotizaton of the main thoracic region at the expense of spinal flexion will just increase the proximal and distal compensatory kyphosis.

With 3D corrections, the priorities are; first, to reduce the Cobb angle, second, to reduce rotation, and third, to reduce morphological flatback.

**Figure 6.** The transverse thoracic view of the thoracic section of a Rigo Chêneau type brace. Derotation of the spine at the thoracic level helps to achieve a more normal physiological sagittal profile of the spine to reduce flatback.

**Figure 7.** These forces are needed to bring the patient into optimal coronal plane correction through a corrective threepoint pressure system and to bring the anterior prominence to a higher level.

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**Figure 8.** The three-point pressure system allows better frontal plane correction, improves collapse of ribs, and brings the ventral rib hump to higher level, resulting in elongation of the spine.

#### **2.3. Rigo Chêneau type brace and Schroth physiotherapeutic scoliosis specific exercises**

The contributions of MR are the description of the biomechanical principles of the brace design and a creation of the specific scoliosis classification developed to help to standardize the brace design and construction. This classification also correlates with Schroth

**Figure 7.** These forces are needed to bring the patient into optimal coronal plane correction through a corrective three-

**Figure 6.** The transverse thoracic view of the thoracic section of a Rigo Chêneau type brace. Derotation of the spine at the

thoracic level helps to achieve a more normal physiological sagittal profile of the spine to reduce flatback.

176 Innovations in Spinal Deformities and Postural Disorders

point pressure system and to bring the anterior prominence to a higher level.

**Figure 9.** This figure shows the same patient on her left and right sides, with two different sagittal plane shapes on each side. The patient is wearing a WCR brace for the treatment of a left thoracic and right lumbar B1 type scoliosis [3].

physiotherapeutic scoliosis specific exercises (PSSE) both according to the Barcelona School (BSPTS) as well as the original German Schroth school according to Katharina Schroth [5].

The Rigo-Chêneau type brace and the Schroth PSSE address the 3D biomechanics of the deformity in the similar way. The increased expansions in the brace correspond to the Schroth PSSE so-called de-rotational breathing mechanics, which strive to expand the collapsed areas of the trunk affected by scoliosis, aiming at correcting the horizontal (axial) plane of the body. Specific pressure areas in the brace and Schroth PSSE principles work hand in hand to correct the frontal and sagittal planes of the body. That is why the Rigo Chêneau type brace and Schroth PSSE are considered to be a 3D conservative treatment of scoliosis.

This three-dimensional correction cannot be achieved using classic braces, commonly used to treat scoliosis for decades, because their biomechanical design generally does not address the rotational aspect of scoliosis.
