MATERIAL and METHODS: This study involved a total of 56 patients between 21 and 79 years old (28 male and 28 female) who had no surgical pathology as documented by lumbar magnetic resonance imaging study. Measurements at L3-4, L4-5, and L5-S1 were performed for both sexes as follows: 1^st measurement, from the furthest lateral part of the dura to the end of the disc (right-left); 2^nd measurement, the anteroposterior length of the cross-section passing through the midline of the disc; 3rd measurement; from the furthest lateral part of the dura to the furthest lateral part of the disc (right-left); 4th measurement, the length from right to left of the cross-section passing through the midline of the disc.

RESULTS: Measurement 1 at L3-4, L4-5, and L5-S1, this value was estimated to be 35.9 and 36.7 mm, 35.9 and 36.9, and 34 and 34.9 mm in the right and left sides respectively, for female subjects. The corresponding values for males were 41.4 and 42.1, 40.6 and 40.9, and 37.4 and 37.7 mm at L3-4, L4-5, and L5-S1, respectively. Measurement 3 in L3-4, L4-5, and L5-S1 disc spaces on the right and left sides in female subjects were 14.8 and 16.3 mm, 15.7 and 17.2 mm, and 14.9 and 17.1 mm, respectively, with corresponding figures of 18.6 and 19.5, 19.7 and 20.6, and 18.2 and 18.6 mm among male participants. Measurement 2 and 4 in females for L3-4, L4-5, and L5-S1 were 38.4 and 52.3 mm, 38.9 and 53.4 mm, and 37 and 51.8 mm, respectively. The corresponding figures for males were 43.2 and 57.6 mm, 43.2 and 58.9 mm, and 40.1 and 56.7 mm, respectively.

CONCLUSION: Determination of the safe discectomy depth in both males and females, as well as the use of marking disc punches to indicate the safe margins may help clinicians to avoid this unwanted complication. Keywords : Lumbar disc surgery, Vascular injury, Intestinal injury, Safe discectomy distance