This paper discusses methods to biomechanically evaluate scoliosis. From a chiropractic point of view, an understanding of the biomechanics of scoliosis is of paramount importance. By understanding the pathogenesis, the chiropractic physician can apply a rational approach to outline a treatment regimen. Spinal curvatures in the median plane change during growth, and in normal children the thoracic kyphosis reduces in size between the ages of 8 to 14. However, the change occurs at different times for boys and girls. Since scoliosis is a lordotic problem, associating lateral curvatures with gender, age, and attitude of the thoracics during growth spurt may answer questions of a female disposition and a male tendency to Scheuermann's disease. Further, this paper evaluates the lateral curvatures of the spine concerning normal curve mechanics and idiopathic scoliosis. Mechanical stability is considered, applying engineering principals to understand buckling and critical loading. By examining the factors of spine slenderness, flexibility and strengths of the trunk muscles, and applying this understanding to curve mechanics-biomechanics of scoliosis, the chiropractor has a rationale for the treatment of mild lateral curves.