
The normal spine viewed from the side forms a gentle "S" shape. When viewed from the back, the normal spine appears straight. The naturally occurring soft curves of the spine are designed to distribute mechanical stress in the body when at rest and during movement. When the curvature is even slightly abnormal, a person may experience occasional mild or annoying discomfort. If the curve is severely abnormal, the pain is usually severe and accompanied by disability. Scoliosis occurs in both children, where it is generally idiopathic, and adults, where it is often acquired.
In 2013, there were nearly 2 million healthcare visits with a diagnosis of scoliosis, the majority of which 1.3 million were to a physician’s office. However, 166,600 hospital discharges had a scoliosis diagnosis. The number of hospital discharges with a scoliosis diagnosis has remained relatively steady for five years (2010 thru 2014) and represents approximately 56 persons in every 100,000 US population. Females accounted for three out of four (73%) of healthcare visits with a scoliosis diagnosis. (Reference Table 2B.2.0 PDF [1] CSV [2] and Table 2B.2.1 PDF [3] CSV [4])
Spinal deformity and scoliosis can be found at birth due to genetic causes, develop during childhood, or occur late in life because of degenerative disc and joint disease. Common signs of scoliosis are a prominent shoulder or shoulder blade, or chest wall asymmetry. Another sign is uneven hips, with one hip seemingly higher than the other hip. It is important not to confuse scoliosis with poor posture and to realize that scoliosis will usually not disappear with age. Despite the severity of these conditions and the impact they have on the lives of children, the prevalence of spinal deformities in children under the age of 18 years is difficult to determine because of relatively low numbers and the degree to which the condition manifests initially in pain or disability. Estimated prevalence of spinal deformity conditions has been cited in numerous studies, and ranges from 0.4 in 1,000 for infantile idiopathic scoliosis1 to 2.5 in 1,000 for adolescent idiopathic scoliosis.2 (Reference Table 2B.1.0 PDF [7] CSV [8])
There are several different types of scoliosis. The most common type of scoliosis is idiopathic, meaning the cause is unknown. Approximately 80% to 85% of scoliosis cases are idiopathic.3 Idiopathic scoliosis can occur as early as the first three years of life, which is known as infantile idiopathic scoliosis. If diagnosed between the ages of 4 to 10 years, it is known as juvenile idiopathic scoliosis, and from 10 years of age to skeletal maturity, as adolescent idiopathic scoliosis. The term “early onset scoliosis” (EOS) is also used to describe scoliosis that occurs prior to 10 years of age. Adolescent idiopathic scoliosis is the most common type.
Scoliosis, if severe enough (>25°), is usually treated with bracing if the child is growing or with surgery if the curvature is more severe (>45° to 50°). The standard radiograph measurement method for all forms of scoliosis is the Cobb angle measurement technique, measured from the end plates of the maximally tilted end vertebral bodies in a standing radiograph.4 Whether the curve is >25° or >40° to 45°, the treatment is preventative in nature, helping to avoid progression of the curve and more significant future problems that might occur if it was left untreated. Increased mortality has been reported in untreated early onset scoliosis due to respiratory conditions.5 While this preventative aspect is hugely valuable and intuitively important, its benefit is difficult to measure from a public health standpoint, especially for rare conditions of childhood such as juvenile and adolescent pediatric scoliosis.
Infantile scoliosis occurs in patients 0-3 years old and currently accounts for less than 1% of all cases of idiopathic scoliosis in the United States. Boys are affected by infantile idiopathic scoliosis at a higher rate than girls (3:2 ratio).1 Infantile scoliosis curves tend to be left-sided (75% to 90%). Past studies have indicated this rare type of scoliosis occurs more frequently in Europe than in North America.6
Treatment for patients with infantile idiopathic scoliosis is determined by anticipated or actual curve progression. Several common measurement techniques are used, with angles ≤20° generally considered at low risk for progression. In addition to measuring the Cobb angle, the rib-vertebra angle difference (RVAD) is used as a common predictor of curve progression.7 Patients with a Cobb angle of ≤25° and a RVAD of ≤20° are at a low risk for progression and should be re-evaluated every 4 to 6 months.1
Nonsurgical treatment, such as bracing or casting, is initiated if a curve progression of ≥10° occurs. Surgical treatment should be considered when nonsurgical measures, including both bracing and casting, are not successful. Surgical treatment is utilized when a curve is ≥45° and progressive in an immature child.1 Overall, surgical methods are continually evolving, with the goal of obtaining and maintaining curve correction while simultaneously preserving or encouraging spinal and trunk growth.
Surgical options currently utilized include various types of spinal fusion or hemiepiphysiodesis, a minimally invasive implant procedure to slow progression of curve growth. Additional techniques include growing-rod instrumentation (rods that expand and support the deformed spine) and vertical expandable (telescoping) prosthetic titanium rib (VEPTR) instrumentation.8 The goal of using surgical methods is to halt the progression of the curve and gain correction of the deformity, while allowing maximum growth of the spine, lungs, and thoracic cage.1 The allowance of normal lung development is one of the critical factors in recommending treatment for infantile and juvenile idiopathic scoliosis. Prevention of early mortality due to respiratory failure is a key driver of surgical treatment of early onset scoliosis.1,5
In 12% to 21% of idiopathic scoliosis cases, the diagnosis is made between 4 and 10 years of age. Between the ages of 4 and 6 years, the female-to-male ratio of juvenile idiopathic scoliosis is 1:1. However, the ratio of female to male cases rises to between 2:1 and 4:1 in children between the ages of 4 and 10 years, and to 8:1 in children who are 10 years of age or older.9 Both right and left curves are found with equal frequency for patients younger than 6 years, but rise to a 3:1 ratio of right versus left thoracic curves after the age of 6.10
Observation is the main treatment for patients with a small curve of less than 20° to 25°. Follow-up visits are recommended every 4, 6, 9, or 12 months, depending on the patient’s age, the degree of the curve, and the characteristics of the clinical deformity.9
Curves between 25° and 50° are usually treated with bracing in this age group. Bracing can be done either on a part- time or full-time basis, depending on the size of the curve as well as the age of the child. A study completed in 1982 evaluating the success of bracing reported an excellent prognosis when part-time bracing was utilized for patients with a curve of ≤35° and RVAD11 of ≤20°; however, curves ≥45° and RVAD of ≥20° had a less favorable prognosis for successful treatment with bracing.9
Overall, the curve patterns in patients with juvenile idiopathic scoliosis are similar to those with adolescent idiopathic scoliosis. Approximately 70% of patients with juvenile idiopathic scoliosis exhibit curve progression and require some form of treatment. In a study conducted in 1981, 55 of 98 patients (56%) with juvenile idiopathic scoliosis required spinal surgery. The most common and traditional surgery is posterior instrumentation and fusion.9
According to the Scoliosis Research Society (SRS), idiopathic scoliosis is diagnosed when a patient has asymmetry on forward bending combined with a curve of at least 10°.12 By this definition, the prevalence of adolescent idiopathic scoliosis in children from 11 to 18 years of age is 2% to 3%. Though the male-to-female ratio for smaller curves is about equal, larger curves seem to be more common in females. Similar results were found in a study conducted in 1985, where 29,195 children were screened for idiopathic scoliosis.2
Several studies have investigated the natural history and natural course of curve progression in adolescent idiopathic scoliosis. All report the strongest predictive factors in the development of idiopathic scoliosis are age, magnitude of curve, and gender.13,14,15,16 Girls are more likely to have adolescent idiopathic scoliosis than boys, and some studies report the onset is earlier in girls than boys. A factor highly correlated with curve progression is age at diagnosis; patients diagnosed at a younger age have a greater risk of curve progression. However, those diagnosed at a younger age seem to have a more favorable response to milder forms of treatment, which supports the practice of school screening to detect and lead to earlier diagnosis for those children who exhibit a smaller degree of curvature.
Treatment decisions for individuals with adolescent idiopathic scoliosis are made based on location, shape, pattern, and cause of the curve. The treatment choice is also a function of the patient’s future growth potential. Treatment choices include observation, bracing, and surgery. Observation is usually reserved for patients who have curves ≤25°. Bracing, which is used to stop curve progression (rather than for lasting correction of the curve), is usually used for patients who have curves ≥25° and who are still growing. Surgery is generally used for patients with curves ≥45°.
Congenital scoliosis is believed to affect approximately one child for every 1,000 live births.17 The cause is unknown in most cases, but in some cases, it is associated with various syndromes, as shown in the illustration below. Diagnosis occasionally is made during prenatal ultrasound. In cases of congenital scoliosis, additional congenital conditions, such as chest wall malformation or kidney or heart abnormalities, are often present. Treatment options for congenital scoliosis are bracing and/or surgery and are similar to treatments discussed for idiopathic scoliosis. Bracing is not as effective for congenital scoliosis as it is for idiopathic scoliosis.
Major abnormal spinal deformity occurring during infancy or early childhood poses a clinical problem because of the anticipated long growth period (at least 10 years), variable presentation and treatment methods, and the length of time that must pass before meaningful outcome results can be assessed in the small number of patients for definitive studies. Curves that result from congenital scoliosis are often not treated as easily as idiopathic curves because the deformity is in the bones rather than the soft tissue, causing the curve to be rigid.18
Scoliosis also occurs in conjunction with several congenital conditions that occur in infancy or childhood. These include muscular dystrophy, cerebral palsy, spina bifida, and spinal muscular atrophy. Scoliosis associated with these conditions is referred to as neuromuscular scoliosis. Both the likelihood and the severity of the scoliosis generally increases with the severity of the underlying condition. For example, a child with severe cerebral palsy who is unable to walk is more likely to have severe scoliosis than a child with mild cerebral palsy who can walk.
Because of the low prevalence of scoliosis in children and adolescents, it is difficult to analyze the healthcare impact on the US healthcare system from this condition. However, the impact of scoliosis over a lifetime due to pain, inability to work, and cost to the healthcare system are substantial.
In 2013, one in three (35%) healthcare visits with a diagnosis of scoliosis was for a person under the age of 18. Most visits, 93% of the 681,100, were classified as idiopathic scoliosis. The majority (93%) of all visits with a diagnosis of scoliosis by persons under age 18 were outpatient visits to either an outpatient clinic or physician office. Only 3.5% represented hospital discharges; however, this still accounted for 23,800 discharges for this often painful condition in children and adolescents. (Reference Table 2B.2.2 PDF [18] CSV [19])
In 2013, 40% of children and adolescents under the age of 18 years discharged from the hospital with a diagnosis of scoliosis had surgery. Spinal fusion was the most common surgery performed (36.1%), followed by incision/excision (24.6%), and deformity monitoring (9.6%). One in seven (15%) also had a blood transfusion. (Reference Table 2B.5.2 PDF [22] CSV [23])
Average hospital charges for patients under 18 years of age with a scoliosis diagnosis in 2013 were five times the average charge for all hospitalized patients in this age group ($113,800 versus $22,400), even though the length of stay was only about 50% longer (6.4 days versus 3.9 days). The high number of surgical procedures likely accounted for some of this variance. The length of stay and mean charges were slightly higher for those with an acquired/secondary scoliosis diagnoses than for those with an idiopathic scoliosis diagnosis. (Reference Table 2B.3.2 PDF [26] CSV [27])
Young people under the age of 18 with scoliosis are four times more likely to be transferred to a long-term care facility and three times more likely to have home healthcare than peers discharged for any diagnosis although the rates are still lower than among older persons (3% and 9%, respectively). (Reference Table 2B.4.2 PDF [32] CSV [33])
Deformity of the adult spine includes patients with curvature of the spine (scoliosis) of varying degrees caused or impacted by degenerative disc and joint disease. Adult scoliosis may be the result of persistent or progressive deformity since adolescence or a new, de novo, onset of deformity resulting from degeneration or aging of the spine. Degenerative scoliosis accounts for most scoliosis cases in older populations aged 65 years and older, as reflected in the low proportion of older patients with a diagnosis of primary idiopathic scoliosis.
Degenerative scoliosis is one of the most challenging spine conditions to treat because of the variability of the condition. Generally, it is thought to originate with the degeneration of the intervertebral discs, which leads to misalignment of the vertebral column. Degenerative scoliosis, particularly in the very elderly, is often associated with other conditions, such as osteoporosis. Treatment outcomes for both nonsurgical and surgical procedures are not well documented; hence, recognition and earlier intervention are important to ward off the more complex problems of adult scoliosis. The role played by undiagnosed, mild idiopathic adolescent scoliosis on the development of degenerative scoliosis in later life is unknown.
The clinical presentation and management of adults with scoliosis is characterized by a great deal of variability. There is a poor correlation between the magnitude of deformity and the impact of scoliosis on health status, as patients with large spinal curvatures may have limited pain and disability and patients with relatively mild deformity may be severely impaired. Deformity in the sagittal plane is associated with disability more than scoliosis.1 Patients with adult scoliosis seek medical care for symptoms, including back pain, neural symptoms, and progression of deformity. It is often neural symptoms secondary to spinal stenosis that leads patients to seek treatment.
The prevalence of adult spinal deformity and scoliosis is not well established, with estimates ranging from 2.5% to 25% of the population.2,3,4,5,6,7 A 2005 study reported mild to severe adult scoliosis prevalence as high as 68% in a healthy (no known scoliosis or spine surgery) population aged 60 years and older.8 Many cases of degenerative scoliosis are undiagnosed, but elderly patients often seek care because of back and leg pain that may be caused by scoliosis and associated spinal stenosis.
According to 2010 US Census Population Estimate, there were 235,205,658 people in the United States over the age of 18 years. Prevalence of adult scoliosis cited in the literature ranges from 2.5% to 60%, depending on severity. A conservative estimate (2.5%) of the prevalence of adult scoliosis yields an incidence of a minimum of 5.88 million adults in the United States with adult scoliosis. In 2013, an estimated 1.28 million of these adults received treatment either as an inpatient or on an outpatient basis. (Reference Table 2B.2.2 PDF [18] CSV [19])
The management of adult scoliosis includes nonsurgical and surgical resources. Nonsurgical treatments of adult scoliosis utilize significant resources, and include interventions such as exercises, physical therapy, injections, pain medications, and manual manipulation.9 Data on nonsurgical treatments is not available; however, a 2010 nonrandomized study reported that two years of nonsurgical treatment in adult scoliosis patients resulted in substantial expenditures and yielded no improvement in health status.10
Operative management of scoliosis in the adult encompasses a spectrum of procedures, including decompression alone, decompression with limited fusion, and fusion of the deformity. The type of procedure performed is typically determined by the predominant symptoms. Neural symptoms in patients with smaller curves (<30 degrees) are treated with decompression alone, while patients with larger curves and neural symptoms are treated with decompression and fusion.11 Adult scoliosis associated with sagittal deformity is more commonly treated with decompression, osteotomies, and larger fusions of greater than four level (five or more vertebrae).12
In 2013, a query of the Healthcare Costs and Utilization Project (HCUP) Nationwide Inpatient Survey (NIS) resulted in approximately 142,600 hospitalizations of people age 18 and over associated with a discharge diagnosis of scoliosis (ICD-9-CM of 373). The majority of these, or 140,200 patients, were diagnosed as idiopathic scoliosis or scoliosis of unknown cause. Hospitalization with a scoliosis diagnosis was higher among the elderly, with those 65 and older accounting for nearly half (43%) among all ages. Females accounted for nearly three-quarters (73%) of all scoliosis hospitalizations. Race/ethnicity and region in the US did not show significant differences. (Reference Table 2B.2.1 PDF [3] CSV [4], Table 2B.2.2 PDF [18] CSV [19], Table 2B.2.3 PDF [36] CSV, [37] Table 2B.2.4 PDF [38] CSV [39])
In 2013, more than one-half (53.6%) of patients with a diagnosis of acquired/secondary scoliosis had a surgical procedure, but only one in five (20.7%) of those with a diagnosis of idiopathic scoliosis had surgery. The most common procedure performed on scoliosis patients was spinal fusion, with 26,600, or 16%, having this procedure. A majority of scoliosis patients with a fusion procedure (83%) had fusion of 4 or more levels. Sex of the patient was not a factor in having a procedure, but persons age 45 to 64 were most likely to have a procedure. (Reference Table 2B.5.0.1 PDF [40] CSV [41], Table 2B.5.0.2 PDF [42] CSV [43], Table 2B.5.1 PDF [44] CSV [45], Table 2B.5.2 PDF [22] CSV [23])
The cost of care for adults with scoliosis includes direct costs and indirect costs of lost wages, time away from work, cost of care providers, and opportunity costs. Estimates of the direct costs of nonsurgical care in adult scoliosis are estimated to be as high as $14,000 per year.10 The national mean cost of a hospitalization, including surgical treatment, for patients with a primary diagnosis of idiopathic scoliosis was $69,400 in 2013 for an average hospital stay of 5.3 days. The mean cost for those with an acquired or secondary scoliosis diagnosis were significantly higher at $120,400 per discharge, with an average stay of 5.9 days. The HCUP NIS database does not provide hospitalization costs associated with secondary discharge diagnoses, and does not include fees to doctors, tests, and other typical charges associated with hospitalization. Therefore, the most conservative estimate of only the hospitalization cost for adult scoliosis, both idiopathic and acquired/secondary in 2013 was an estimated $11.5 billion (166,600 hospitalizations). Charges are not necessarily actual costs paid. Mean charges for scoliosis diagnosed patients are significantly higher than for all hospital discharge patients. (Reference Table 2B.3.2 PDF [26] CSV [27])
In 2013, slightly more than one-half (58%) of patients with a scoliosis diagnosis were discharged to home, while 70% of patients with any diagnosis had a routine discharge. Patients with a scoliosis diagnosis are more likely to be transferred to a skilled nursing or intermediate care facility (long-term care) than are patients with all diagnoses. This is particularly true for the elderly population, with 39% of persons age 65 and older with a scoliosis diagnosis moving to a long-term care facility. (Reference Table 2B.4.2 PDF [32] CSV [33])
The real cost of the management of adult scoliosis to our healthcare system is significant, and the value of care measured by change in health status remains incompletely defined for both nonsurgical and surgical care.
Links:
[1] https://bmus.latticegroup.com/docs/bmus_e4_T2B.2.0.pdf
[2] https://bmus.latticegroup.com/docs/bmus_e4_T2B.2.0.csv
[3] https://bmus.latticegroup.com/docs/bmus_e4_T2B.2.1.pdf
[4] https://bmus.latticegroup.com/docs/bmus_e4_T2B.2.1.csv
[5] https://bmus.latticegroup.com/file/bmuse4g2b210png
[6] https://bmus.latticegroup.com/docs/bmus_e4_g2b.2.1.0.png
[7] https://bmus.latticegroup.com/docs/bmus_e4_T2B.1.0.pdf
[8] https://bmus.latticegroup.com/docs/bmus_e4_T2B.1.0.csv
[9] https://bmus.latticegroup.com/file/cobb-anglepng
[10] https://bmus.latticegroup.com/docs/cobb-angle.png
[11] https://bmus.latticegroup.com/file/adolescent-prevalencepng
[12] https://bmus.latticegroup.com/docs/adolescent%20prevalence.png
[13] https://bmus.latticegroup.com/file/congenital-scoliosis-syndromespng
[14] https://bmus.latticegroup.com/docs/congenital%20scoliosis%20syndromes.png
[15] https://www.srs.org/patients-and-families/conditions-and-treatments/parents/scoliosis
[16] http://www.ncbi.nlm.nih.gov/pubmed/15931035
[17] http://www.wheelessonline.com/ortho/congenital_scoliosis_and_vertebral_defects
[18] https://bmus.latticegroup.com/docs/bmus_e4_T2B.2.2.pdf
[19] https://bmus.latticegroup.com/docs/bmus_e4_T2B.2.2.csv
[20] https://bmus.latticegroup.com/file/bmuse4g2b211png
[21] https://bmus.latticegroup.com/docs/bmus_e4_g2b.2.1.1.png
[22] https://bmus.latticegroup.com/docs/bmus_e4_T2B.5.2.pdf
[23] https://bmus.latticegroup.com/docs/bmus_e4_T2B.5.2.csv
[24] https://bmus.latticegroup.com/file/bmuse4g2b212png
[25] https://bmus.latticegroup.com/docs/bmus_e4_g2b.2.1.2.png
[26] https://bmus.latticegroup.com/docs/bmus_e4_T2B.3.2.pdf
[27] https://bmus.latticegroup.com/docs/bmus_e4_T2B.3.2.csv
[28] https://bmus.latticegroup.com/file/bmuse4g2b213png
[29] https://bmus.latticegroup.com/docs/bmus_e4_g2b.2.1.3.png
[30] https://bmus.latticegroup.com/file/bmuse4g2b214png
[31] https://bmus.latticegroup.com/docs/bmus_e4_g2b.2.1.4.png
[32] https://bmus.latticegroup.com/docs/bmus_e4_T2B.4.2.pdf
[33] https://bmus.latticegroup.com/docs/bmus_e4_T2B.4.2.csv
[34] https://bmus.latticegroup.com/file/bmuse4g2b221png
[35] https://bmus.latticegroup.com/docs/bmus_e4_g2b.2.2.1.png
[36] https://bmus.latticegroup.com/docs/bmus_e4_T2B.2.3.pdf
[37] https://bmus.latticegroup.com/docs/bmus_e4_T2B.2.3.csv
[38] https://bmus.latticegroup.com/docs/bmus_e4_T2B.2.4.pdf
[39] https://bmus.latticegroup.com/docs/bmus_e4_T2B.2.4.csv
[40] https://bmus.latticegroup.com/docs/bmus_e4_T2B.5.0.1.pdf
[41] https://bmus.latticegroup.com/docs/bmus_e4_T2B.5.0.1.csv
[42] https://bmus.latticegroup.com/docs/bmus_e4_T2B.5.0.2.pdf
[43] https://bmus.latticegroup.com/docs/bmus_e4_T2B.5.0.2.csv
[44] https://bmus.latticegroup.com/docs/bmus_e4_T2B.5.1.pdf
[45] https://bmus.latticegroup.com/docs/bmus_e4_T2B.5.1.csv
[46] https://bmus.latticegroup.com/file/bmuse4g2b222png
[47] https://bmus.latticegroup.com/docs/bmus_e4_g2b.2.2.2.png
[48] https://bmus.latticegroup.com/file/bmuse4g2b223png
[49] https://bmus.latticegroup.com/docs/bmus_e4_g2b.2.2.3.png
[50] https://bmus.latticegroup.com/file/bmuse4g2b224png
[51] https://bmus.latticegroup.com/docs/bmus_e4_g2b.2.2.4.png