Scoliosis is a sideways curve of the spine that often develops just before puberty, according to the Mayo Clinic, but people of all ages can have it. Sometimes conditions like cerebral palsy or muscular dystrophy can lead to scoliosis, but most cases have no known cause.
That includes having bad posture or carrying heavy backpacks, says Paul David Sponseller, M.D., Chief of John Hopkins Medicine's Division of Pediatric Orthopedic Medicine. While those may contribute to other back problems, they do not lead to scoliosis. Doctors do know that the disease does have a hereditary component though, meaning it runs in families.