Development and evaluation of thoracic kyphosis and lumbar lordosis during growth

We developed a pantograph to measure dorsal curves. It consisted of a tripod-supported vertical strut to which an articulated bar was fixed and which had an arm that was able to follow the dorsal surface while moving up and down. This arm was positioned over the C7 spinous process and followed spinous processes to L5 at constant speed. A laser beam was used to ensure the proper positioning of the pantograph and the subject. The motion was recorded using software so that the dorsal outline was represented on a computer screen, and lordotic and kyphotic curves were automatically measured. Before performing the population study, the pantograph was validated in 20 normal subjects by comparing the pantograph measurements with lateral spine radiographs. There were no statistically significant differences in the measurements. There were 718 subjects with no race selection, of whom 350 were males and 368 females ranging in age from 5 to 20 years and presenting normal weight and height. Individuals with generalized ligament laxity, trunk asymmetry, muscle retraction, or any orthopedic anomaly were excluded from the study. Data were analyzed according to age and gender. Student’s t tests and regression analysis were performed.