Current concepts and controversies on adolescent idiopathic scoliosis: Part I

Abstract

Adolescent idiopathic scoliosis is the most common spinal deformity encountered by General Orthopaedic Surgeons. Etiology remains unclear and current research focuses on genetic factors that may influence scoliosis development and risk of progression. Delayed diagnosis can result in severe deformities which affect the coronal and sagittal planes, as well as the rib cage, waistline symmetry, and shoulder balance. Patient's dissatisfaction in terms of physical appearance and mechanical back pain, as well as the risk for curve deterioration are usually the reasons for treatment. Conservative management involves mainly bracing with the aim to stop or slow down scoliosis progression during growth and if possible prevent the need for surgical treatment. This is mainly indicated in young compliant patients with a large amount of remaining growth and progressive curvatures. Scoliosis correction is indicated for severe or progressive curves which produce significant cosmetic deformity, muscular pain, and patient discontent. Posterior spinal arthrodesis with Harrington instrumentation and bone grafting was the first attempt to correct the coronal deformity and replace in situ fusion. This was associated with high pseudarthrosis rates, need for postoperative immobilization, and flattening of sagittal spinal contour. Segmental correction techniques were introduced along with the Luque rods, Harri-Luque, and Wisconsin systems. Correction in both coronal and sagittal planes was not satisfactory and high rates of nonunion persisted until Cotrel and Dubousset introduced the concept of global spinal derotation. Development of pedicle screws provided a powerful tool to correct three-dimensional vertebral deformity and opened a new era in the treatment of scoliosis.

Keywords: Adolescent idiopathic scoliosis; clinical examination; natural history; radiological assessment; treatment.

Figure 1

(a) Clinical photograph of a male patient showing a thoracolumbar scoliosis undergoing plaster molding for a Boston brace using the Risser frame and longitudinal traction (b) initial posteroanterior radiograph of the spine showing the template for positioning of the corrective pad. (c) repeat radiograph of the spine (at 6 weeks) which shows adequate location of the apical pad (wire marker) and good support of the spine with the scoliosis corrected from 35 to 7°

Figure 2

Clinical photograph (a) and spinal radiograph (b) on a female adolescent patient shows a severe right thoracic and left lumbar scoliosis. (c-d) a posterior spinal fusion with the use of Luque segmental wire/rod instrumentation and autologous iliac crest bone graft produced a balanced spine in the coronal plane with level shoulders and symmetrical waist line

Figure 3

(a,b) Clinical photograph and spinal radiograph of a female adolescent patient show a severe right thoracic scoliosis producing elevation of the right shoulder, prominence of the scapula and ribs adjacent to the convexity of the curve, as well as thoracic translocation to the right and waistline asymmetry with prominence of the left side of the pelvis. (c, d) a posterior spinal fusion with the use of hybrid hook/screw/rod instrumentation and autologous iliac crest bone graft achieved a balanced spine in the coronal plane with level shoulders and symmetrical waist line