**1.2 Anatomo-pathological classification of painful instabilities**

a.Thoracolumbar pain often corresponds to minor joint instability.

b.The pain of convexity is of muscular origin.

c.The pain of the concavity is posterior: facet syndrome.

d.The lumbosacral pain is of ligament origin.

These pains respond perfectly to physiotherapy.

When scoliosis progresses, it is either (1) the evolution in adulthood of an adolescent idiopathic scoliosis, (2) a de novo scoliosis usually of discal origin, or (3) a camptocormia of muscular origin. In all cases, there may be a disc disease with sometimes rotatory dislocation, postural impairment with imbalance, extrapyramidal muscle involvement, and bone involvement (osteoporosis). In these progressive cases of instability, bracing or surgery may be necessary.

### **1.3 Classification of painful instabilities according to age**

a.From 20 to 30 years old, the main problem is the anatomical pain.


### **1.4 Natural history of idiopathic scoliosis from adolescent to adulthood**

Early works on scoliosis progression in adulthood were pessimistic [12], but at this time, idiopathic scoliosis, especially rachitic infantile, is mixed with neurological poliomyelitis that no longer exists.

In 2003 Weinstein published the spontaneous evolution of 117 idiopathic scolioses over more than 50 years [13]. Thoracic curves of more than 50 degrees at skeletal maturity progressed with an average of 29.4 degrees. Thoracolumbar curves between 50 and 75 degrees increased with an average of 22.3 degrees. Lumbar curves had the most progression, especially when the L5 vertebra was not well seated and when the apical rotation was greater than 33%. He does not observe a functional respiratory or painful repercussion below 70°. This angulation could be currently the functional surgical Cobb limit. Pregnancy does not change the progression of scoliosis in adulthood, except in cases of twin pregnancy.

### **1.5 The two distinct entities**

In 2007 Marty-Poumarat [14] describes two specific adult scoliosis entities: adolescent scoliosis in adult (ASA) and degenerative de novo scoliosis (DDS).

Group A (ASA) = adult progression of AIS > 40° with first dislocation at 45 years. The progression can be sometimes regular, sometimes chaotic.

Group B (DDS) = de novo scoliosis with low Cobb after 50°, first dislocation at 52 years after menopause. DDS is more progressive than AIS. Because DDS is a result of degenerative disc instability, it is almost always progressive. Lumbar and thoracolumbar are the most progressive degenerative curves. Duval-Beaupere and Dubousset [15] have first described the mechanism of rotatory subluxation. Following their work, many authors have insisted on the importance of the lumbo-pelvic parameters [16–18].

### **1.6 Risk factors for instability**

The radiological risk factors for instability are (1) rotatory dislocation with lateral olisthesis (**Figure 1**), (2) L3–L4 inclination, (3) hypolordosis, and (4) increased thoracolumbar kyphosis [19–20].

### **1.7 Indications of bracing**

The physical activity and fracture rate of adult scoliosis is identical to that of the general population, except for operated patients who have less physical activity [21]. Unlike adolescence, when bracing is systematic when scoliosis progresses, the corrective bracing indication in adults is less related to Cobb angulation but more to the instability which results in pain, abnormal angular evolution, or imbalances (**Figure 2**).

From a database started in 1998, we selected all adult scoliosis in which conservative orthopedic treatment has been proposed to, even if the treatment had not been achieved by the patient. Scoliosis treated during adolescence and monitored in adulthood were excluded [22]. In this case series study, we analyzed 779 patients referred for nonsurgical treatment, and we correlated three parameters: the etiology, age, and Cobb angulation (**Table 1**).

### **Figure 1.**

*De novo scoliosis with constitution of a rotatory dislocation in 2 years, then scoliosis worsening by osteoporotic cuneiformization.*

*Bracing Adult Scoliosis: From Immobilization to Correction of Adult Scoliosis DOI: http://dx.doi.org/10.5772/intechopen.90196*

**Figure 2.** *Clinical imbalances in the frontal and the sagittal planes.*


### **Table 1.**

*Main indications for adult scoliosis bracing with frequency classification.*

The rate of dropout patients not wearing the brace is 17% which is not excessive, especially since the plaster cast at that time was made before the brace discouraged patients.

A tentative classification according to etiology, age, and angulation is proposed (**Figure 3**).

More than half of the indications concern the rotational dislocation, which is the specific complication of adult scoliosis. The rotary dislocation is visible on the CT scan with subluxation and joint narrowing on the sliding side and widening of the articular space on the opposite side.

One-fourth of the indications concern disc instability, which can be considered as the early stage of rotational dislocation.

The other etiologies are less frequent: lumbar-pelvic-femoral kyphosis, secondary instability under arthrodesis, root pain, and rarely spinal stenosis which requires neurosurgery. Camptocormia is linked to weakness of the deep posterior musculature [23]. The patient increases kyphosis gradually to tighten his weak paravertebral muscles. There is often an extrapyramidal context of Parkinson's

### **Figure 3.**

*Indications of nonsurgical treatment by etiology (n = 739).*

disease [23]. MRI cross sections highlight the fatty degeneration. Some authors have mentioned paravertebral myopathy [24].

According to age, there is no Cobb angle difference between patients aged 39 and 80 years old, even if we notice a slight worsening between patients aged 80 and 90 years old. It can be concluded that after 40 years, for the same angulation, the risk of decompensation does not depend on age [22].

If we examine in more detail the distribution of patients according to Cobb angle, we find that Cobb angle is not a discriminating factor like aging.

### **1.8 Eligibility test**

One of the bracing eligibility tests especially for camptocormia is self-correction by using the hands on the thighs, even if this self-correction does not last long in time. The second test of reducibility is carried out in supine position. The occipital patient must rely on the plane of the examination table. The placement of the ARTbrace is performed by the patient who stabilizes the brace at the pelvic level then unrolls the spine using the rigidity of the posterior bar and finally blocks the upper part. As for children, the "mayonnaise tube" effect of the two lateral hemivalves completes the correction in the sagittal plane.
