Scoliosis is a curvature of the spine in the coronal plane with one or more segments deviating from the midline of the body to the lateral side, most often accompanied by rotation of the spine and increased or decreased sagittal lordosis or anterior lordosis, rotational tilt deformities of the ribs and pelvis, and abnormalities of the paravertebral ligaments and muscles. It is a symptom or x-ray sign. There are many causes of scoliosis, but idiopathic scoliosis is the most common and its cause is unclear, accounting for about 80% of all scoliosis. It occurs in adolescents, especially in females, and often develops during prepubertal development, progresses rapidly throughout adolescence, and progresses slowly in adulthood or sometimes stops. Because the cause of most scoliosis is unknown, patients sometimes have abnormalities of the nervous system, endocrine system, and nutritional metabolism.
The Scoliosis Research Society (SRS) defines the diagnostic criteria for scoliosis as a spine with a Cobb’s angle greater than 10 degrees measured in the coronal plane.
Etiological classification of scoliosis
I. Non-structural scoliosis or functional scoliosis
This includes postural malformation, hysterical, and nerve root irritation, such as scoliosis caused by nucleus pulposus protrusion or tumor irritation of nerve roots. There are also scoliosis caused by unequal length of both lower limbs, hip contracture, and certain inflammatory diseases. After treatment of the cause, scoliosis can be eliminated.
Second, structural scoliosis
(A) Idiopathic scoliosis
Idiopathic scoliosis of unknown cause is the most common, accounting for about 75% to 80% of the total number of scoliosis. It is further divided into infantile type (0-3 years), juvenile type (3-10 years) and adolescent type (after 10 years) according to its age of onset. Although these three age groups are theoretically consistent with spinal growth, the spine grows rapidly in the infantile and adolescent stages and more steadily in the juvenile stage.Dickson et al. concluded that since scoliosis develops most rapidly during the growth spurt, the juvenile form is no longer necessary and suggested that idiopathic scoliosis be divided into two groups: the early onset group (0-5 years) and the late onset group ( >5 years of age). However, in terms of cardiopulmonary function, it is more clinically relevant to distinguish idiopathic scoliosis by the age of 5 years. Clinical observations have shown that many life-threatening cardiopulmonary deformities that are combined with scoliosis often progress to severe scoliosis by 5 years of age and that this age cut-off correlates with postnatal development, so that the early-onset group has the highest risk of developing restrictive lung disease, pulmonary hypertension, etc. Also, long-term follow-up studies of adolescent-type idiopathic scoliosis have shown that pulmonary function, even when the degree of scoliosis exceeds 100°, still (ii) Congenital scoliosis
(ii) Congenital scoliosis
There are three types of scoliosis based on the developmental disorders of the spine.
1. formation disorders, with hemivertebrae and cuneiform vertebrae.
2, poor segmentation, with unilateral undifferentiated formation of bony bridges and bilateral undifferentiated (blocked vertebrae, bloc vertebrae).
3, mixed type.
Studies have shown that the vast majority of congenital scoliosis is progressive, with only 10-25% of patients not progressing. mcMaster and Ohtsuka studied 202 patients and found that only 11% were non-progressive, 14% were mildly progressive, and 75% were significantly progressive. The rate of progression of the deformity depended on the type of deformity and the length of the affected spine. mcMaster reviewed 59 patients and found that scoliosis of the thoracolumbar segment had the worst prognosis. The worst prognosis was found when the Cobb angle was greater than 50 by two years of age. Unilateral undivided bridges with single/multiple convex lateral hemivertebrae had the worst prognosis for thoracic curvature. The following order is unilateral unsegmented bridge, biconvex hemivertebra, single convex hemivertebra, and blocked vertebra (bloc vertebra, i.e., bilateral segmentation disorder) have the best prognosis. Due to the progression of certain deformities (e.g., unilateral bony bridges), such as unilateral bony bridges that cause lack of growth on the concave side of the flexure and produce severe deformity if the convex side continues to grow, it is difficult to correct a stiff deformity without the use of only unconventional surgery. Therefore, treatment should be based on the principle of preventing the progression of the deformity, and such patients should not wait for its development, but should be fused early.
(c) Neuromuscular scoliosis.
(iv) Neurofibromatosis combined with scoliosis.
It is highly hereditary and accounts for about 2% of the total number of cases. It is characterized by six or more café-au-lait spots on the skin and some have limited rubbery neuromas. The deformity is continuously progressive and can progress even after surgery; the incidence of pseudarthrosis is high, often requiring multiple bone graft fusions and difficult to treat.
(v) Mesenchymal lesions combined with scoliosis.
Marfan syndrome and Edam syndrome are both mesenchymal lesions. About 40% to 75% of patients with Marfan syndrome have scoliosis. It is characterized by severe scoliosis, often painful, pulmonary dysfunction, and clinical manifestations such as long and thin body shape, elongated fingers (toes), funnel chest, corpus cavernosum, high palatal arch, ligamentous laxity, flat feet, and aortic and mitral valve insufficiency. Edam syndrome is characterized by short neck.
(F) Osteochondral dystrophy combined with scoliosis
This includes curvilinear deformation of dwarfism, mucopolysaccharide accumulation disease, spinal bone marrow dysplasia, etc.
(vii) Metabolic disorders combined with scoliosis
Such as rickets, osteogenesis imperfecta, homocystinuria, etc.
(H) Scoliosis due to contracture of extra-spinal tissues
Such as abscess chest or after burns, etc.
(ix) Others
1, trauma, such as fracture, after laminectomy, thoracoplasty, scoliosis caused by radiation therapy.
2, spinal slippage, congenital lumbosacral joint deformity, etc.
3, rheumatism, bone infection, tumor, etc.