Lateral curvature to the spine of this 10-year-old girl may indicate scoliosis, which is one of the most commonly diagnosed spinal deformities and is characterized by lateral curvature of the spine and spinal rotation. Although scoliosis may result from congenital or pathologic conditions, it is most often determined to be idiopathic (of unknown cause). It is commonly first noticed during periods of rapid growth, particularly during early adolescence in girls. Screenings may occur in schools or at well-child office visits for girls age 10-12 and for boys age 13-14. Early detection and prompt treatment may reduce the need for surgical intervention.

(Option 1) Genu varum (bowlegs), the lateral bowing of the legs, is common in toddlers as they learn to walk. The condition resolves by 18-24 months after they develop strength in their legs and lower back. After 2 years, normal alignment will again progress to valgus deformity until age 4 and then will return to normal adult alignment by age 7. All of this is a normal physiologic alignment.

(Option 2) A rounded, nearly circular chest shape with the front-to-back (anteroposterior) diameter approximately equal to the side-to-side (lateral) diameter is an expected finding in a healthy infant. The chest is more oval and the lateral diameter is greater than the anteroposterior diameter by age 2.

(Option 4) An S, heart sound, reflecting rapid filling of the left ventricle, is considered normal when heard in children. This sound is heard in diastole immediately after S₂ as a dull, low-pitched sound. Sy is heard louder in the mitral or apical area, which distinguishes it from a split S₂ that is heard best in the pulmonic area.

Educational objective:
An S, heart sound is a normal finding in children. Bowlegs are common until age 18 months. Scoliosis is always abnormal. Early detection and prompt treatment of scoliosis may reduce the need for surgical intervention.