This is where lateral (toward the side of your spine) curvature which can be observed in an otherwise normally straight, vertical line. When viewed from the side, the spine should show a mild roundness in the upper back and a varying degree of swayback (inward curvature) in the lower back.
When a person with a normal spine is viewed from the front or back, the spine appears to be straight. When a person with scoliosis is viewed from the front or back, the spine appears to be curved. When someone with a scoliosis bends forwards a ‘rib hump’ can be seen whereby one side of the spine is proud on forward bending.