Scoliosis: Clinical and Therapeutic Point of View

1- Definition:

Scoliosis is a deviation of the spine that is always presented with a deformation in the frontal plane. However, X-rays and patient examination shows that there is a three-dimensional deformation in the frontal, sagittal and horizontal with a vertebral rotation causing a hump. Overall, there are two types of deviation in the frontal plane:

• the scoliosis, a curvature flexible, low amplitude, disappearing in the supine position, a benign course, present in 10% of infants and adolescents. This curvature is never associated with a deviation in the horizontal plane, so there is never any hump.

• Structural curvatures: it is the true scoliosis, curvature fixed with rotational component. They are identified by analyzing clinically the thoracic or lumbar asymmetry secondary to vertebral rotation. Structural curvatures affect less than 2% of a population of adolescents.

Scoliosis: Clinical and Therapeutic Point of ViewAmong the structural bends, there is 70% of curvatures called idiopathic and 30% of secondary curvatures to recognized conditions. Non idiopathic scoliosis are congenital curvature (vertebral malformations default segmentation, or extra half vertebra), neurological bends (BMI, muscular dystrophy, polio), secondary bends the patient to Recklinghausen, metabolic or ligament problems ( Marfan disease, Lobstein disease).

These curvatures are usually discovered by their basic disease and because of their great progress.

2- Idiopathic scoliosis:

The so-called scoliosis “idiopathic” scoliosis is having its own existence and is not the consequence of another. This is a spinal deformity consisting of a relative displacement and progressive one vertebra relative to its adjacent vertebrae occurring in the three planes of space, without loss of bone and ligament continuity, primarily during periods growth.

The overall treatment of idiopathic scoliosis (IS) includes 4 main stages:

• screening;

• monitoring developments;

• conservative treatment;

• surgical treatment.

The goal of this program is to stabilize the spine, through the growth, in a form and a useful function for the duration of adulthood.

3- Scalability and natural history:

In childhood and adolescence, the SI is a painless condition whose only symptom is spinal deformity, except for very severe forms outset that compromise respiratory function.

The risk of progression is assessed for each case, because that’s only risk which should be the basis for the therapeutic indication. DUVAL-BEAUPERE studied the relationship between worsening SI with growth and bone maturation. The initial slope of worsening scoliosis is slow and, from the first signs of puberty, it gets worse from two to eight times to curb bone maturation in again.

The age of onset of a curve determine the end of growth angle. Infant IF (1-4 years) still reach 100 ° when fully grown but only 32% of SI discoveries of 4 to 7 years will reach 100 °, 13% of those found between 7 and 11 years and 4% of those discoveries between 11 years and puberty. The risk of progression for boys, comparable curves, is ten times less than up for girls. More growth is rapid in puberty, the risk of change is important.

The angular aggravation will be greatest for curves measuring from 60 to 80 ° in bone maturation, because for the highest curves, mechanical factors (ribs, axial compaction, interarticularis osteoarthritis or interbody) limit the angular worsening . In general, a new rapid decompensation spurt occurs during menopause.

The long-term clinical consequences are the following such a patient aged 50 years, 90 ° curve:

• pain: 40 to 60% of patients with severe idiopathic scoliosis complain of back pain, compared with the average population incidence. However, the pain of scoliosis are larger and more frequent. In the lumbar and thoracolumbar curves in particular, whether a rotational translation are at the lower end of the curve, there is a higher proportion of disabling back pain. The thoracolumbar curves create a significant imbalance of the trunk causing a very significant fatigue due to muscular effort of active balancing it causes. However, the intensity of back pain is not related to the existence or not of osteoarthritic phenomena or the severity of the curve.

• The pulmonary function quietly disturbed in thoracic curves from 60 ° but it is beyond 100 ° as mechanical ventilation will be worsened with a decrease in vital capacity and maximum expiration second volume, this parallel to increase in the curve. In the long term, right heart failure and a fatal pulmonary hypertension alter the prognosis.

Nowadays, social integration also depends on the appearance. The presence of a hump or a chest imbalance is very poorly supported by adolescents.

Rarer are the appearance of neurological disorders, digestive and overall physical stunting.

4- Screening:

Spontaneously idiopathic scoliosis are discovered by relatives when the bending angle is about 40 degrees, then it is too late to initiate an effective conservative treatment. We must therefore track the SI in pre-pubertal age for the presence of a hump over 5 °. In a positive test a total column radiography is the basis of the measurement, the curvatures of more than 25 ° will be processed, the other are followed to document progression.

5- Therapeutic indication:

Overall, the therapeutic indication If a child or young person will be based on three elements:

1. the certainty of the diagnosis of idiopathic scoliosis with its deformation structural criteria in the 3 spatial planes (frontal planes, sagittal and transverse) and the elimination of other causes of scoliosis (neurological, congenital).

2. The precise study of the curvature and evaluation of scalability and residual growth.

The means of surveillance and effective treatments available and knowledge of their side effects.

The first therapeutic step: screening and surveillance.Tous industrialized countries have introduced early school screening by clinical examination, by angular extent of the hump, or documentation of spinal asymmetries through photographs shimmering example.

The most effective screening will be conducted between 10 and 12 years before the great pubertal growth spurt or at its beginning. During these inspections

30% of children will be credited a trivial asymmetry,

• 2 to 3% will have scoliosis angles greater than 10 °;

• 0.3 to 0.5% of angles greater than 20 °;

• 0.1 to 0.3% of angles of 30 °;

• 0.1% of angles greater than 40 °;

• 0.2% of these children will be justifiable from a conservative or operative treatment.

6- Conservative treatments:

Conventional methods of conservative treatment of scoliosis are applied, after screening, on curves of about 25 degrees, which showed a progressive trend in growing patients.

The Milwaukee brace developed by Blount SCHMIT and is composed of a pelvic mold supporting masts on which is fixed a collar which must provide a self effect permanent elongation. Support hands putting pressure on humps. This corset requires frequent adjustments and is easily tolerated psychological perspective. It has the merit of being the first effective corset and very long-term results are available. For curves of 30 to 39 °, with an average control more than 10 years, the evolution is as follows:

• corset-up angle: 34.8 °;

• corset best angle: 16.6 °;

• angle of the output of the corset: 24.2 °;

• Last control (11.6 years): 30.8 °.

BOSTON The corset is a prefabricated orthosis to adapt quickly, well tolerated by patients. The corrective effect is immediate with pelvic support, lumbar and thoracic only. The effect of the correction is made by previous support post and coupled on the protuberances and by voids left inside the corset and which allow the correction to take place in the frontal and transverse plane.

For a group of 102 patients with a mean curve of 33.6 ° to the corset layout, the angle control at one year following the end of treatment was 30.4 °.

The cons-indications of brace treatment can be formal or relative. formal cons-indications are: bone maturation over, the curves exceeding 45 ° to 50 °, severe obesity and uncooperative patient. The against-indications concern curves accompanied by chest lordosis or whose apex is cranial to D5, which in principle are refractory to all conservative treatment.

Many spinal orthoses recovery exists, the efficiency criteria of a corset are: immediate correction of more than 50% of the initial curvature, lack of progress made in radiation monitoring off-set horn. Physiotherapy is an adjuvant that preserves good flexibility a muscle capital during the duration of the post of the corset.

7- Surgical treatments:

Only surgery can long maintain the significant correction of spinal deviation. Will be operated scoliosis fairly high angle to be poorly tolerated or at risk of evolution into adulthood. These are curvatures of more than 50 ° in thoracic area and 40 ° lumbar area and continue their evolution throughout life.
The basic principle of any surgery will fix (arthrodesis) scoliotic vertebrae together to prevent further deterioration and maintain an overall balance of the front and side trunk. It must however be remembered that spine fusion will never be a normal spine, either in its form or in its function .. This will require proper selection of fusion levels. The angular correction will be useful only if two conditions are met, namely: a solid and balanced fusion.

The vast majority of currently operated curves has angles of 45 ° to 60 °, they are carried by posterior route. Against by the curves of more than 90 ° require a prior release time by throracoscopie or thoracotomy. In particularly rigid curves, a surgical time of release followed by a traction halo may be necessary.
A lumbar and thoracolumbar floor, it is also possible to previous interbody arthrodesis in compression. These techniques allow angular and rotational corrections very efficient even though the number of fused levels is less important. The main advantage of these methods is to maintain the largest possible number of mobile disks lumbar area.

To reduce to the maximum the immediate and late complications of this major surgery, a number of precautions must be taken. Preoperative planning precisely defines the levels to be instrumented, the type of equipment to implement and the importance of achievable security Correction. The anesthetic team must be able to control hypotension techniques to reduce blood loss in association with autologous transfusion and blood recovery.

The major operative risk remains ischemic spinal cord lesion that appears with a frequency of 0.2 to 0.5%. A measured distraction, preoperative alarm and recording of somatosensory evoked potentials are the precautions to take to avoid this complication always disastrous. The risk of infection is currently controlled by antibiotic prophylaxis.Long-term complications are represented by the appearance of nonunion and hardware failure, the progression of a curve whose fixation levels are insufficient or poorly chosen finally by the appearance of low back pain due to disc overload residual free lumbar area.

Author: André Kaelin (Pediatric Orthopedics, Children’s Hospital, GENEVA)