[Relationships between the height of intervertebral discs and the degree of lordosis of the cervical spine in children. A roentgenometric study (author's transl)].

On lateral roentgenograms of the cervical spine of 120 normal children between 3 and 14 years of age the ventral and dorsal height of all 5 intervertebral discs were measured and the "index of the intervertebral disc" was calculated. In addition, the "degree of lordosis" of the cervical spine was determined according to ISHIHARA (1964). Evaluation was in 3 age groups: 3 to 6, 7 to 10, 11 to 14 years; and the arithmetic mean and standard deviation were calculated for each group. All intervertebral discs are more or less "cuneiform" (ventrally higher than dorsally); they narrow from cranial to caudal. In children the degree of lordosis of the cervical spine shows a continuous decrease with advancing years. In all age groups girls show a lower degree of lordosis than boys. Statistically the differences of average values of the intervertebral-disc-index among the various shapes of the cervical spine in neutral position (straight, sublordotic, lordotic and hyperlordotic) are highly significant. By means of roentgenometric methods our examinations demonstrate that the lordotic curvature of the healthy cervical spine primarily depends on the cuneiform shape of intervertebral discs.