Universal screening for scoliosis is not an absolute practice in the United States of America, but most states and school systems support screening of asymptomatic preadolescents and adolescents. In 2004, the U.S. Preventive Services Task Force (USPSTF) had an acute change in their position and recommended against the routine screening of adolescents for idiopathic scoliosis. In the wake of this decision many medical societies (American Academy of Pediatrics, American Academy of Orthopaedic Surgeons, Pediatric Orthopaedic Society of North America, and the Scoliosis Research Society) formed consensus statements further recommending scoliosis screening. All four societies recognize the benefits that can be provided by effective clinical screening programs, including (1) the potential prevention of
deformity progression by brace treatment and (2) the earlier recognition of severe deformities requiring operative correction. With recent evidence, from the Bracing in Adolescents with Idiopathic Scoliosis Trial (BrAIST) study, supporting the efficacy of bracing in the treatment of moderate curves, there may be increased support for school screening programs.

Screening is performed using the Adams forward bending test. With the patient bending forward from the waist, the examiner views the patient from behind for thoracic asymmetry, from in front for lumbar asymmetry, and from the side for assessment of kyphosis. A rib prominence seen with the forward bending test is from rotation of the spine and can be measured with an inclinometer (Fig. 22.2). An angle of trunk rotation (ATR) measurement of 7 degrees is the current recommendation for referral to an orthopaedist; this was established from screening data gathered by Bunnell. The data from his scoliosis screening research also showed that 98% of patients with an ATR 5 degrees or less will have a Cobb angle <20 degrees on x-ray, but that figure decreases to 94% at 6 degrees, 88% at 7 degrees, and 50% at 10 degrees. With this level of screening, approximately 10% of children referred require treatment. With newer evidence outlining the importance of awareness in radiation exposure to the growing patient, it is important to note that not all patient referrals lead to the procurement of radiographs. However, each patient should have a thorough examination by a medical professional before radiographs of the spine are obtained. The ATR cutoff of 7 degrees on the inclinometer favors a type 1 error, but prevents missing patients with curves who are likely to progress.

As in all medical conditions, an accurate history is vital in the diagnosis and management of idiopathic scoliosis. In addition to routine questions (age, gender, medical history, family history, and social history) the following points should be queried in the initial patient encounter:

The examination in scoliotic deformity should include current height and weight, presence of secondary sexual characteristics, dermatologic examination (café au lait spots, which may indicate neurofibromatosis), neurologic examination, limb length, and assessment for signs of spinal dysraphism (patch of hair or dimple along the spine).

The standing patient should be assessed for asymmetry of the trunk, back, shoulder, and neckline. The Adams forward bend test can then be used in conjunction with an inclinometer to evaluate rotational deformity. The patient should be viewed from the side, while performing the forward bend, to assess for any kyphosis in the thoracic spine. An inclinometer reading of 7 degrees is roughly correlated with a radiographic Cobb angle measurement of 15 to 20 degrees (Fig. 22.2). Leg length discrepancy is a common reason for spurious diagnoses of spinal curvature. Leg lengths can be measured supine or standing, but if a leg length discrepancy exists then it should be taken into account (typically with a measured wooden block that levels the pelvis) before further physical examination or radiographic evaluation.

The standard neurologic assessment for scoliosis patient includes strength testing, deep tendon reflexes, straight leg raise, Babinski sign, abdominal reflexes, and examination for clonus. In patients where stenosis or intrathecal anomaly is suspected more specific tests may be performed.

In scoliosis, radiographs allow for diagnosis, quantification of curve, serial observation, and treatment planning. The standard screening radiograph is a standing posteroanterior (PA) radiograph on a 36-in cassette which should measure from the occiput to the pelvis in most patients. The PA view allows for assessment of coronal plane deformity as well as some inference of the axial plane based on rotation. If the pelvis is included in the screening PA radiograph then the surgeon can make commentary on the Risser sign (Fig. 22.3) as well as the status of the triradiate cartilage, which are indicators of bony maturity. An approximation of any leg length difference can also be made based on a PA radiograph that includes the iliac crest or top of the femoral heads. Lateral radiographs, also taken on a full size cassette, allow for examination of the sagittal profile. Often the lateral radiograph is omitted during the screening process and acquired once a diagnosis of scoliosis is made or if there is concern for kyphosis or spondylolisthesis.

The apical vertebra is used to describe the location of the curve or curves (thoracic, thoracolumbar, or lumbar), and the Cobb method is used to measure the coronal plane magnitude of the curve. The Cobb method is performed by marking the end plates on the most tilted vertebrae at the top and bottom of the curve. The angle of intersection between the lines (formed by the end plates) is the Cobb angle (Fig. 22.4). Measured angles of less than 10 degrees are considered to be normal
physiologic variation, but curves greater than 10 degrees are considered scoliotic curvatures and should be followed for progression. The timing and frequency of follow-up appointments are different for each patient and surgeon, but, as a general rule, immature patient with larger curves should be followed closely (every 4 to 6 months), whereas more mature patients with smaller curves can be followed with less frequency.

Assessing maturity with regard to growth remaining is an important factor that may influence potential treatment. In addition to the Risser sign and the status of the triradiate cartilage, hand x-ray for bone age and use of the Sanders epiphyseal staging method may prove useful and may be more accurate than pelvic findings. The peak height velocity is the time when risk of curve progression may be greatest, but unfortunately many commonly used methods for skeletal maturity assessment such as the Risser sign are not visible until after the peak height velocity has passed. Other systems such as assessing the ossification of the proximal ulna has been shown to be useful prior to peak height velocity, however this tool has not been widely accepted.

During surgical planning, in addition to standard PA radiographs, a lateral x-ray of the spine and bending films is obtained. The lateral will be used to assess thoracic kyphosis and overall sagittal balance. It is also possible to make commentary on rib-hump deformity from the lateral radiograph, but this is more reliably viewed during the physical examination. Bending films assess the flexibility of a given curve. The patient will bend into the curve (often over a bolster) and the radiograph is taken. Curves that remain greater than 25 degrees on bending films are considered structural in nature.

When following young patients over a long period of time it is worthwhile to consider minimizing radiation exposure and risk either through radiographic technique (low exposure methods and anatomically placed shields) or by obtaining fewer x-rays in stable curves. Data from the 1960s and 1970s suggest a 1% to 2% increase in lifetime risk of breast and thyroid cancer for patients exposed to multiple spinal radiographs during treatment of spinal curvatures. Since that time x-ray protocols and techniques have changed drastically to reduce radiation exposure. New x-ray technology, such as the EOS (Cambridge, MA) machine, is emerging with the capability to decrease radiation exposure to an even greater extent.

Magnetic resonance imaging (MRI) is not required for all cases in the treatment of AIS. MRI should be obtained if the curve is atypical (apex to the left), if there is associated back pain (concern for infection or malignancy), if there has been a heightened pace of curve progression, or if there is any neurologic abnormality (concern for intraspinal process, such as syrinx, tethering, or tumor).

Observation. Patients who have a spinal curvature that is less than 25 degrees can be serially observed either by their primary care physician or orthopaedist. In general, curves smaller than 10 degrees can be followed clinically without radiation exposure from serial radiographs. Patients with true scoliosis (curve >10 degrees) should be monitored clinically and radiographically, particularly immature patients. This group of patients should be evaluated every 4 to 6 months until such time as a decision for surgical intervention is made, or until they reach skeletal maturity.

Bracing. Historically, there has been controversy in the brace management of scoliosis secondary to a dearth of reliable data in the bracing literature. The data are confounded by use of different brace types, materials used, hours in-brace prescribed, quality of brace fabrication, and general opinion of bracing by the treating physician. In 2013, the BrAIST results were
published in The New England Journal of Medicine. This was a prospective randomized clinic trial that confirmed the clinical efficacy of bracing using a Boston style thoracolumbosacral orthosis (TLSO) brace (Fig. 22.5). Another important finding from the BrAIST data was the prescribed (and worn) hours of bracing; patients who wore the brace >13 hours per day did not require posterior spinal fusion (PSF) 90% of the time, while patients who wore the brace <6 hours per day had similar surgery rates as patients treated with observation alone.