TOPOGRAPHIC VARIABILITY OF SIZEs AND SHAPEs OF INTERVERTEBRAL FORAMENs of LUMBAR SPINEs
Background. The article identifies patterns of topographical, sexual and bilateral variability of sizes and shapes of intervertebral foramens of lumbar spines. Materials and methods. By CT and MRT of men and women of I and II periods of mature age (men - 22-60 years old, women - 21-55 years old) with no signs of injuries, scoliosis, systemic and degenerative diseases of the spine ( n = 140), the authors determined dimensions (vertical, horizontal diameter and area) and shapes of intervertebral foramens of lumbar spines, using the PACS sytem (Picture Archiving and Communication System) - a system of transmission and archiving of images. A variational statistical analysis was performed using the Statistica 6.0 package. Results. Several shapes of foramens were marked out: oval, rectangular, triangular, figure-eight-shaped, guttaformical (inverted-drop-shaped), slit-shaped, semilunar, rounded, laсrimаfоrmical (teardrop-shaped). The foramen area in men has increased from 129,99 ± 6,17 mm<sup>2</sup> in the chest-lumbar transition to 141,25 ± 6,83 mm<sup>2</sup> at L<sub>II</sub>-L<sub>III</sub> and reduced to 78,9 ± 5,33 mm<sup>2</sup> in the lumbosacral junction; the invertebral foramen area in women has increased from 118,89 ± 8,30 mm<sup>2</sup> in the chest-lumbar transition to 128,0 ± 6,62 mm<sup>2</sup> at L<sub>II</sub>-L<sub>III</sub> and reduced to 59,85 ± 8,56 mm<sup>2</sup> in the lumbosacral transition. A considerable bilateral dissymmetry is typical for intervertebral foramen shapes; the foramen shape on the left and right sides coincides only in 12 % of cases. Conclusion. Thus, topographical (the size increases to the top of the lumbar lordosis), sex (manifested by prevalence of sizes in men than women) and fluctuating bilateral dissymmetry are typical for sizes of intervertebral foramens. Shaps of foramens vary; shape extensiveness changes depending on the level of the orifice.