Is the definition of scoliosis still a 20 percent discrepancy from a straight line? This medical definition may have kept me from knowing that my estimated 10 percent discrepancy was likely related to a life-long tendency to pull muscles, joint stiffness especially in my lower back, with more frequent injuries from accidents and over use on just one side, from head to toe. My first symptoms were in adolescence, beginning with a stiff and sore back, a maintenance issue that I minimize with stretching (yoga and pilates), swimming, and sleeping on my back with my knees elevated. In college (and again in my forties with an MRI), doctors measured my leg length, but found no discrepancy. In my thirties an orthopedist recommended PT and balancing my genetic flexibility with strength building exercises. Swimming, aerobics (low impact), and lifting light weights helped to "straighten" the "short" side. My fifties brought yoga to my work place, and a traditional form of Pilates that actually worsened back pain. [Only in my sixties, when I again tried Pilates, and an evolved method of teaching, in addition to yoga, did I find that Pilates helped.] Also in my fifties, an orthopedist expressed surprise that I did not know about my curvy spine. He showed me an x-ray of my back and what I describe now as a "minor" scoliosis, about ten percent. Over time, I understood that this "shortened" side, is the same length as the other side, but appears shortened because of a curvy spine that tilts body parts above and below, resulting in a "curvy" alignment, not just a curvy spine. One measure for me as to how well I am managing to maintain the alignment of my body parts, as straight as possible, and the flexibility of my joints and the strength of my muscles, is standing with flat feet, bending my knees halfway, and observing whether my knees are in the same place with respect to my feet, or if one is turning inward -- it could be outward for someone else -- it just depends. And even if your knees are in the same place with respect to your feet, as mine are now, consider whether you feel more pressure on one joint or another. Hope this helps just one other person.