Answer:
Scoliosis
Step-by-step explanation:
Scoliosis is an abnormal curvature of the spine to one side of the trunk, determined by the rotation of the vertebrae. Deformity can be seen by looking at the person from the back.
In other words: the main feature of scoliosis is the presence of a lateral curvature in the three-dimensional plane of movement (left / right, front / back and around the axis itself by rotation of a vertebra) which gives it the appearance of a C (a single curvature) or an S (more than one curvature).