The term idiopathic scoliosis refers to structural scoliosis of unknown origin. This type of scoliosis, which can start at any period during the growth period, constitutes 80% of all scoliosis. It is often seen to the right in the thoracic (back) region, to the left in the lumbar region (waist) and is more common in girls.
Idiopathic scoliosis is divided into four groups according to the age at which deformity begins.
Infantile idiopathic scoliosis: It is seen under 3 years of age, usually and frequently in men, with left thoracic curvatures, and it has no compensatory curvature.
Juvenile idiopathic scoliosis: It is seen between the ages of 4-10 years, it is seen more in boys at younger ages and more in girls at older ages. They are left/right thoracic curvatures and they are progressive.
Adolescent idiopathic scoliosis: Until the completion of 10-year-skeletal development, they are frequent in girls, and are right thoracic curvatures.
Adult idiopathic scoliosis: It is seen in older ages.
The curvature of the patient’s body is noticed by the family or him/herself. There may be visible bends in the body, uneven shoulders, rarely low back and back pain, and rarely respiratory distress. The age of onset of the disease and the sex of the patient are very important. The patient’s body balance and scoliosis measurements and neurological examination are examined.
For complete and detailed preoperative evaluation, direct scoliosis radiographs are taken in various ways such as standing, lying down and traction. MRI is requested because of the possibility of spinal cord lesions, especially in early patients. Spinal cord and soft tissues are examined in detail with Magnetic Resonance Imaging (MRI). If necessary, detailed and three-dimensional examination of the bones can be performed with computed tomography (CT). After all these radiological examinations are completed, the type of scoliosis, the degree of curvature, the curvature’s location, type, flexibility, and skeletal maturity are decided.
Knowing the natural course of scoliosis detected in the patient is important in the selection of treatment methods that will be performed to the patient. The most important problem with scoliosis is the progression of the deformity and the additional problems caused by the deformity. The goal of scoliosis treatment is to try to stop the curvature until bone maturation is complete and to try to correct the curvature after completion. Factors that may affect the risk of progression of idiopathic scoliosis are skeletal maturity, degree of curvature at the time of diagnosis, location, and type of curvature, and gender of the patient.
In idiopathic scoliosis, there is a high potential for progression, especially in patients with incomplete bone growth, and it is very difficult to accurately predict the limits of this progression. For girls, it is the period 6 months before seeing which scoliosis reach the peak height velocity of growth. This is also the period of fastest progression in scoliosis. Scoliosis is more progressive in girls than in boys. If the scoliosis angle is above 30°, the probability of progression in girls is 7 times higher. Scoliosis below 30° is unlikely to progress in the adult patient group. Wide curvatures (30°-40°) progress faster than small curvatures (20°-29°). The type of curvature is also an important factor in progress. The thoracic (back) region tends to progress faster than the lumbar region. It is known that initiation of treatment in idiopathic scoliosis at a young age prevents the curvature from reaching the surgical limits in many cases.
Adolescent idiopathic scoliosis
The aim of surgical treatment is to obtain a straight and balanced spine by maintaining a good body balance, to stop the progression of curvature, to provide an acceptable cosmetic appearance, to create a shoulder balance, to ensure the development of chest cage and respiratory function is good. It is known that long-term severe low back, back pain and serious psychological problems (low rate of marriage) are observed in the non-operated individuals. The timing of surgery is as important as the type and strategy of surgery in these patients who will undergo surgery for these purposes.
Although the curvatures in some patients are at the surgical limits, the decision of surgical treatment may be delayed by considering factors such as trunk and height growth. Although the degree of scoliosis is below the reported standard values sometimes, surgical treatment may be recommended. In fact, the cause of demanding late surgery in patients is due to not to affect the patient’s growth potential. However, in the meantime, the excessive progression of the deformity may lead to early surgery which because of becoming riskier of surgical intervention. As conventional knowledge, surgery is recommended for curvatures with an angle greater than 40° and, after the completion of maturation of the skeletal system, curvatures greater than 45°. However, surgical treatment criteria and timing of the surgery are not strictly determined, and the nature of the patient and scoliosis for surgery depends on the joint decision of the family and surgical team.
All spinal curvatures diagnosed before the age of 10 years are defined as early-onset scoliosis. There is no single definite guideline for the treatment of these patients. Although congenital scoliosis is also seen in young ages, surgical treatment is not explained in this section but in its own section. Timely diagnosis, monitoring, and treatment of infantile idiopathic scoliosis and juvenile idiopathic scoliosis patients are very important. 5 years of age is very important for the development of the heart and lung. Lung tissue may also develop until the age of 8 years. It is known that early-onset scoliosis may cause long-term cardiac and lung problems. The main purpose of follow-up and treatment is to reduce or stop the progression of the deformity without blocking the thoracic (chest cage) development and spinal elongation. Usually, fusion (bone union) is not performed while performing stabilization in these surgical techniques developed for this purpose. While some deformity correction is achieved in this way, the main objective is to prevent the progression of scoliosis. However, after maturation of the skeletal system is achieved, correction of the deformity by conventional fusion surgery will still be performed.