Investigation on the Prevalence and Etiology of Adolescent Idiopathic Scoliosis in Nanchang Region

Scoliosis is a three-dimensional structural deformity of the spine that includes lateral curvature of the spine in the coronal plane, rotation in the horizontal plane, and alteration of the physiologic curvature in the sagittal plane. Scoliosis has an insidious onset and is often overlooked as there are no obvious symptoms in the early stages. As the disease progresses, it may lead to physical deformities, low back pain, decreased cardiorespiratory function, and may also cause psychological problems such as anxiety and depression. According to statistics, the global prevalence of scoliosis is 2-3%, and adolescent scoliosis is the most common type of scoliosis. The prevalence of scoliosis in adolescent females is higher than that of males. In recent years, the incidence of scoliosis has been on the rise as primary and secondary school students experience increased academic pressure and reduced physical activity and sleep time, which has caused great concern in society.

Scoliosis is thought to be associated with a variety of risk factors, including low BMI, gender differences, racial differences, asymmetrical backpack carrying, low physical activity, and prolonged screen viewing. However, despite the identification of many factors contributing to scoliosis, the comprehensive pathogenesis and natural progression of scoliosis are unknown.

Delaware pioneered school-based scoliosis screening in the 1960s, and it has since gradually spread throughout the United States, Canada, and Europe. Most studies have shown that early scoliosis screening is an effective way to prevent the progression of scoliosis in adolescents and reduce surgery rates. However, the implementation of mandatory scoliosis screening is controversial. Opponents of school-based scoliosis screening programs argue that, from a public health perspective, adolescent idiopathic scoliosis screening programs are not supported by sufficient evidence; from an economic perspective, school-based scoliosis screening requires a significant investment in human, material, and financial resources, and school-based scoliosis screening programs have not demonstrated significant cost-effectiveness.

The objectives of this study were to screen the prevalence of scoliosis among primary and secondary school students.

Study population Inclusion criteria: adolescents aged 9 to 14 years in primary and secondary schools.Exclusion criteria: congenital scoliosis, traumatic scoliosis, spinal tuberculosis, and other diseases caused by scoliosis.

Screening Methods In this study, 400 adolescents aged 9-12 years (from selected elementary schools) and 13-14 years (from middle schools) in Nanchang were screened. Prior to the assessment, basic information of the participants (including age, sex, height, weight, BMI, and medical history) was collected. Professional rehabilitation therapists evaluated the participants' posture and spinal rotation angles to determine the presence of scoliosis. Participants suspected of having scoliosis underwent further anteroposterior and lateral X-ray examinations for confirmation. Researchers collected data from the anteroposterior and lateral X-rays, including Cobb angle, Risser grade, Nash-Moe grade, and curve type. For participants diagnosed with scoliosis, additional parameters such as plantar pressure distribution, balance function, and respiratory function were collected.

① Plantar Pressure Measurement The specific procedure is as follows: The Footscan high-frequency plantar pressure distribution system (Belgium) was used. Participants stood barefoot on the pressure plate with their feet shoulder-width apart, looking at a target 1 meter ahead. Their arms hung naturally at their sides, and they breathed normally. After maintaining a stable posture for approximately 1 minute, the pressure sensor readings were recorded. Due to variations in height and body weight, the pressure data collected in this study were expressed as percentages of total plantar pressure. The selected parameters included total pressure on the left foot, total pressure on the right foot, forefoot pressure on both sides, and hindfoot pressure on both sides.

②Standard Posture Assessment

The specific procedure is as follows: The participant stood bareback with feet shoulder-width apart, eyes looking straight ahead, arms hanging naturally, and palms facing inward. The following were assessed:

1. Whether the shoulders were level;
2. Whether the scapulae were symmetrical;
3. Whether the inferior angles of the scapulae were at the same level;
4. Whether the lumbar concavities were symmetrical;
5. Whether the spinous process line was centered.

• Adams Forward Bend Test The specific procedure is as follows: The participant stood upright with knees straight and feet together, then slowly bent forward to approximately 90° with arms extended and palms joined, gradually placing the hands between the knees. During this process, the examiner observed whether the participant's back showed any asymmetry or unevenness.
• Angle of Trunk Rotation (ATR) Measurement A scoliometer was used to measure the degree of spinal rotation during the forward bend test. A reading greater than 5° was considered positive.
• Standing Anteroposterior X-ray of the Spine The specific procedure is as follows: For patients of normal build, the X-ray settings were typically 120 kV, 200 mA, and 1 second. All patients underwent standing anteroposterior X-rays with feet shoulder-width apart, knees naturally extended, facing the X-ray tube, and hands raised with palms forward. If the leg length discrepancy exceeded 2 cm, the shorter side was elevated to keep the pelvis level. The central axis of the X-ray beam was aligned as closely as possible with the sagittal midline of the spine. A measurement scale was placed appropriately. A Cobb angle greater than 10° was diagnostic of scoliosis.