Scoliosis usually occurs in the thoracic spine and in the thoracolumbar segment of the crest between the thorax and the lumbar region, or, of course, in the lumbar region alone. The thoracic curvature looks like this: the lumbar curvature looks like this: the scoliosis occurs on one side of the crest or in the anterior-posterior direction (commonly known as a hunchback) and has a ‘C’ shape, or it may occur bilaterally and have an ‘S’ shape. C-shaped: C-shaped scoliosis is characterized by a concentration of crests whose curvatures are shifted to one side, such as the thoracic and sometimes the lumbar spine. The left or right C-shape abnormality is determined by the direction of the curvature arc, i.e., when the crest is curved to the right, the crestal scoliosis is defined as a right C-shape of the crest, and vice versa. S-shape: S-shaped crestal scoliosis is characterized by at least two arcs offset from both sides from both sides of the crestal midline, for example, the upper arc is offset to the right in the thoracic portion and the lower arc is offset to the left in the lumbar portion. It is important to note that there is a primary curvature of the S-shaped crestal scoliosis prominence, versus another compensatory curvature. Because the direction of deviation is different, treatment of this abnormality is more complex and requires more care. Causes of “hunchback”: 1. Idiopathic scoliosis “Idiopathic” means that the cause is unknown. We do not know exactly what causes this most common form of scoliosis (80-85%), and it is thought to be related to genetic, hormonal, endocrine, growth and developmental abnormalities and neurological balance system dysfunction. 2. Congenital scoliosis The term “congenital” does not refer to a completely genetic condition, but rather to abnormalities in vertebral morphology and structure that occur during fetal development: one or more crestal structures are not fully formed, or the crestal vertebrae are not normally segmented. This type of scoliosis may be associated with other conditions, such as malformations of the heart or kidneys. Congenital scoliosis of the crest is associated with genetic factors, but also with a variety of environmental factors such as lack of oxygen or vitamin deficiency during embryonic development during pregnancy. 3, neurofibromatosis crestal scoliosis This is caused by the erosion of the crestal vertebral body destruction by neurofibroma, the root cause of which is neurofibroma. 4, neuromuscular scoliosis of the crest Any disease involving nerves and muscles can lead to scoliosis of the crest, the most common cause is due to muscle imbalance and muscle weakness. Common neuromuscular disorders that cause scoliosis include cerebral palsy, myasthenia gravis, and cremasteric injury. 5, degenerative scoliosis This type of scoliosis often occurs in older adults, especially older women, because of degenerative disc aging and crestal osteoporosis. Special note: postural scoliosis is not true scoliosis! The biggest difference between the two is that postural scoliosis can be corrected by the body itself, while true scoliosis cannot be corrected by the body itself.