Scoliosis is a sideways curvature of the spine that occurs most often during the growth spurt just before puberty. While scoliosis can be caused by conditions such as cerebral palsy and muscular dystrophy, the cause of most scoliosis is unknown.
Most cases of scoliosis are mild, but some children develop spine deformities that continue to get more severe as they grow. Severe scoliosis can be disabling. An especially severe spinal curve can reduce the amount of space within the chest, making it difficult for the lungs to function properly.
Signs and symptoms of scoliosis may include uneven shoulders, one shoulder blade that appears more prominent than the other, uneven waist, and one hip higher than the other. If a scoliosis curve gets worse, the spine will also rotate or twist, in addition to curving side to side. This causes the ribs on one side of the body to stick out farther than on the other side.
Scoliosis, Mayo Clinic (Dec. 29, 2017), https://www.mayoclinic.org/diseases-conditions/scoliosis/symptoms-causes/syc-20350716