Background:

Scoliosis is a lateral curvature of the spine of 10° or more, often with a rotational component; adolescent idiopathic scoliosis (AIS) is the most common form of scoliosis in adolescence. Curves progress in approximately two-thirds of AIS patients before they reach skeletal maturity. Curves of greater than 40° at the end of growth are likely to continue to progress after skeletal maturity, while curves of less than 30° at skeletal maturity are unlikely to progress significantly during adulthood. Very large degrees of curvature may be associated with adverse long-term health outcomes.

Purpose:

The U.S. Preventive Services Task Force will use this evidence review to update its 2004 recommendation on screening for AIS.

Data Sources:

Cochrane Central Register of Controlled Trials, OVID Medline, ERIC (Eric.ed.gov), PubMed (publisher-supplied), Cumulative Index to Nursing and Allied Health Literature, and relevant systematic reviews. We searched for articles published from January 1966 to October 31, 2015. We updated our search on October 20, 2016.

Study Selection:

Two reviewers independently reviewed 8,230 titles and abstracts and 1,088 articles against prespecified inclusion criteria, resolving discrepancies through consensus. We included fair- or good-quality studies. For screening questions (Key Questions [KQs] 1, 2, and 5), the population of interest was asymptomatic children ages 10 to 18 years, screened in primary care–referable settings using the forward bend test (FBT) with or without a scoliometer, surface topography, or other methods. For treatment questions (KQs 3 and 6), we included studies of children and adolescents ages 10 to 18 years diagnosed with AIS with a Cobb angle of 10° to 50° at detection. For long-term outcomes (KQ 4), we included randomized, controlled trials (RCTs), controlled trials, or large observational studies of adult health outcomes in persons diagnosed with AIS with a Cobb angle of 10° or greater.

Data Extraction and Analysis:

We extracted key elements of included studies into standardized evidence tables. Evidence tables were tailored for each KQ and to specific study designs. We provided a narrative synthesis of results. Because of heterogeneity between studies, we did not conduct pooling or meta-analyses.

Results:

We included seven studies (13 articles) on screening accuracy (KQ 2), seven studies (nine articles) on the effectiveness of treatment (KQ 3), one study (two articles) on the harms of treatment (KQ 6), and two studies (five articles) on long-term outcomes (KQ 4). No studies met our inclusion criteria on the effect of AIS screening on long-term health outcomes (KQ 1) or on the harms of screening (KQ 5).

KQ 1. Does screening for AIS improve: a) health outcomes, and b) the degree of abnormal spinal curvature in childhood or adulthood? No studies.

KQ 2. What is the accuracy of screening for AIS? Seven fair-quality screening programs (13 articles) including 447,243 adolescents met our inclusion criteria. Six of the seven programs were conducted in school settings, and there was heterogeneity in the screening tests used and in the training of the practitioners conducting screening. Three of the seven studies included some followup data on children who screened negative.

Screening accuracy increased with the number of screening tests used. Sensitivity and specificity were highest (93.8% and 99.2%), predictive value was highest (81.0%), and false-positive rates were lowest (0.8% [6.2% false-negative]) in a clinic-based screening program using FBT, scoliometer, and Moiré topography screening; accuracy was lower (71.1% sensitivity, 97.1% specificity, 2.9% false-positive, 28.9% false-negative) in a U.S.-based study of FBT with scoliometer. Sensitivity for single-modality screening in a school-based program screening children age 8 years and older ranged from 84.4 percent with FBT alone to 100 percent with Moiré topography. False-positive rates ranged from 0.8 to 21.5 percent; false-negative rates ranged from 0 percent for Moiré topography to 15.6 percent for FBT alone, with 28.9 percent for FBT plus or minus scoliometer. Predictive value estimates were 29.3 to 54.1 percent for FBT plus scoliometer, and ranged from 5.0 to 17.3 percent for a single screening modality to 81.0 percent for FBT with scoliometer and Moiré topography.

KQ 3. Does treatment of AIS that has a Cobb angle of less than 50° at diagnosis improve: a) health outcomes, and b) the degree of spinal curvature in childhood or adulthood? We found seven studies (nine articles) on the effectiveness of treatment. Five studies (seven articles) of 651 adolescents examined effectiveness of bracing treatment. Three of these studies were of fair quality and two were of good quality. Two studies (two articles) of 184 adolescents examined effectiveness of exercise treatment. One of these studies was of good quality and one was of fair quality.

Brace treatment: Four of five prospective controlled studies found evidence for benefit of bracing treatment on curve progression compared to observed controls, measured either in favorable proportions of children with 5° to 6° of progression (three of five studies) or in curve progression to a degree considered bracing failure (one study). Quality of life outcomes associated with bracing were reported in one study and were similar between treatment arms.

Exercise treatment: In two studies (one good-quality RCT and one fair-quality controlled clinical trial) of tailored physiotherapeutic scoliosis-specific exercise, the intervention group experienced significant improvement compared to a generic exercise control group at 12-month followup. In the RCT, there was a favorable reduction in Cobb angle of 4.9° in the intervention group compared to the control group's unfavorable increase of 2.8° (p<0.001). Quality of life measures were improved at 12 months in the intervention group compared to stable or slightly improving measures in the control group. By the end of the trial's 12-month treatment period, the intervention group had experienced a favorable decrease in average magnitude of all curves of 0.67° compared to the control group's unfavorable progression of 1.38° (p<0.05).

Surgical treatment: No studies of surgical treatment in screening-relevant populations met our inclusion criteria.

KQ 4. What is the association between severity of spinal curvature in adolescence and health outcomes in adulthood? Two fair-quality studies (five articles) of 339 persons with AIS followed up in adulthood met our inclusion criteria. In both studies, adult outcomes were stratified by treatment received in adolescence. Quality of life as measured by the Scoliosis Research Society (SRS)-22 Patient Questionnaire or the 36-Item Short-Form Survey were similar between observed and braced participants at adult followup, though braced participants felt their body appearance was more distorted than did untreated participants, and braced participants reported more negative treatment experiences than those treated surgically. No significant adult outcome differences were found between braced and surgically-treated participants on the Oswestry Disability Index, general well-being, or self-esteem and social activity. Pulmonary outcomes and childbearing and pregnancy outcomes were similar in braced and surgically-treated participants.

KQ 5. What are the harms of screening for AIS? No studies.

KQ 6. What are the harms of treatment of AIS that has a Cobb angle of less than 50° at diagnosis? Harms of bracing were reported in one good-quality study (two articles) of 242 adolescents. Skin problems on the trunk (under the brace) and nonback body pains were more frequently reported in braced participants than in observed controls. Anxiety and depression rates were low and similar between groups. One of the 146 braced participants reported anxiety and depression requiring hospitalization.

Limitations:

Direct evidence for a benefit of AIS screening into adulthood is lacking. Screening programs vary with regard to setting, persons administering the screening test, and screening modalities used, and have very limited followup of screen-negative children. Data on surgery in screen-detected children whose curves have progressed is lacking. Long-term followup studies rarely report data on curve in adolescence and its association with adult health outcomes. We found no evidence on possible harms of screening (e.g., radiation exposure, overtreatment, and/or psychosocial consequences associated with diagnosis of clinically insignificant scoliosis), and very limited data on harms of treatment.

Conclusions:

We found no direct evidence for a benefit of AIS screening in adolescence on adult health outcomes. AIS can be identified with screening with varying accuracy. There is little evidence addressing harms of screening. A growing body of evidence suggests that brace treatment can interrupt or slow scoliosis progression, and two studies suggest that curves of smaller magnitude may respond similarly to physiotherapeutic scoliosis-specific exercise treatment. There is very limited direct evidence on the association between curve magnitude at skeletal maturity and adult health outcomes for persons with mild-to-moderate scoliosis curves at diagnosis.