Idiopathic scoliosis is the most common form of structural scoliosis, accounting for approximately 80% of all scoliosis. Although a great deal of research has been conducted on the etiology of idiopathic scoliosis, its cause is still unclear, hence the name idiopathic scoliosis. According to the age of first diagnosis, idiopathic scoliosis can be divided into infantile idiopathic scoliosis, juvenile idiopathic scoliosis, adolescent idiopathic scoliosis, and ais. scoliosis (ais) and adult idiopathic scoliosis (ais). Among them, adolescent idiopathic scoliosis is the most common, accounting for about 80% of the population with idiopathic scoliosis. Li Ming, Department of Spine Surgery, Shanghai Changhai Hospital
Causes
The pathogenesis of idiopathic scoliosis is unknown, but studies have found that it may be related to the following factors.
(i) Genetic factors: Epidemiological studies of idiopathic scoliosis suggest that there is a clear genetic influence on its occurrence. The exact mode of inheritance is unknown, and most scholars believe that it is related to autosomal dominance and incomplete sexual linkage and diversity of expression. This seems to explain the sex characteristics of the disease distribution, where the ratio of males to females is approximately equal in patients with scoliosis around 20◦ ; however, in the scoliosis population larger than 20◦ , the ratio of females to males exceeds 5:1, and the majority of patients with severe curvature requiring treatment are girls. Statistically, children of two parents with scoliosis are 50 times more likely to have the disease than normal.
(b) Hormonal effects: Girls with idiopathic scoliosis are often taller than normal girls of the same age, suggesting that scoliosis may be related to growth hormone, but a large number of studies have concluded that growth hormone is not the true cause of spinal deformity. The control of growth is complex because growth requires the interaction of multiple factors, including growth factors.
(iii) Abnormal connective tissue development: Patients with idiopathic scoliosis can be found to have qualitative and quantitative abnormalities of collagen and proteoglycans in the connective tissue. Whether this is a primary or secondary factor in scoliosis has not yet been determined.
(iv) Dysfunction of the neuro-balance system: The function of the human balance system is to control the gravitational forces acting on the body and to maintain balance in various states. If there is a dysfunction in one of the reflexes of this balance system, scoliosis may occur in the spine to adjust or establish a new balance.
(E) Abnormalities in the neuroendocrine system: Many scholars have shown that melatonin and 5-hydroxytryptamine play an important role in the formation of is. The scoliosis model that occurs after the removal of the pineal gland in chickens is one of the classic animal models for scoliosis, and the main role of the pineal gland is to secrete melatonin.
(vi) Others: Some clinical observations have shown that the offspring of elderly mothers are prone to idiopathic scoliosis and progress more rapidly. In addition, abnormal copper metabolism may play a role in the development of idiopathic scoliosis.
Natural history
Most adolescent idiopathic scoliosis progresses before adulthood, and the likelihood and extent of progression is related to the following factors.
Sex : Progression occurs more often in girls.
Age : The progression of scoliosis is age-related, with rapid progression at the onset of puberty, and the younger the age of onset, the more likely scoliosis is to progress.
Menstruation : The progression of scoliosis is more frequent before menstruation.
risser sign : ossification of the anterior superior iliac spine is associated with the progression of scoliosis. The risser sign divides the ossification into four stages: from 1 to 4 degrees, with 0 degrees being no ossification and 5 degrees being complete closure of the epiphysis and iliac bone. As risser’s sign increases, the likelihood of progression decreases.
Type of curvature: The onset of progression is related to the type of scoliosis. In general, double curves are more likely to progress than single curves. The most likely types of progression tend to be double thoracic bend, double thoracic bend and lumbar bend, and single right thoracic bend. Single lumbar bends are the least likely to progress.
Angle of scoliosis : The progression of scoliosis increases with the angle of scoliosis.
Diagnosis
(A) Medical history
1, Early detection: Scoliosis is first discovered unintentionally by parents or teachers, and is manifested by unequal shoulders and unilateral scapulae protruding backwards.
2. Clinical symptoms: Curvature of the spine to one side is often the main symptom at the time of first diagnosis, and there are also asymmetries of the trunk when standing, such as unequal height of both shoulders, backward protrusion of one scapula, and asymmetry of the anterior chest. Severe scoliosis can lead to thoracic collapse, trunk imbalance, trunk shortening and decreased endurance due to decreased thoracic volume, shortness of breath, palpitations, etc. A few patients may experience low back pain. In some patients, scoliosis is unintentionally discovered and the deformity can be inconspicuous.
Family history: Although the relationship between ais and heredity has not yet been clarified, clinical observations have revealed that ais has a certain genetic predisposition. It is important to know the usual health status, intelligence level, and maternal history of pregnancy and childbirth to rule out non-idiopathic scoliosis. For example, knowing the patient’s birth history and history of polio can help distinguish between cerebral palsy caused by a difficult birth and scoliosis after polio.
4, Personal history: A detailed personal history can help determine the natural course of scoliosis, such as the age of onset and progression of scoliosis. Most idiopathic scoliosis develops during adolescent development and progresses rapidly during the rapid growth period.