Proposal of a new anatomical landmark to identify the disc space in endoscopic lumbar discectomy

INTRODUCTION: In endoscopic lumbar discectomy for posterolateral disc herniation, we determined some anatomical landmarks for improved disc space access. These landmarks are based on the beginning of the insertion of the ligamentum flavum (LF) to vertebral lamina. MATERIALS AND METHODS: In 978 patients operated by posterolateral disc herniation, we measured prospectively the distance between the beginning of the insertion of the LF and space disc rostrally. RESULTS: The distance between the beginning of the insertion of the LF and space disc was broader at the level of L3–L4, with an average of 14 mm. At L4–L5, the average distance was 13.5. At L5–S1, the average distance was 12 mm. CONCLUSION: Knowing the accurate distance between the insertion of LF and disc space contributes to reducing the average duration of the surgical procedure to avoid empirical search of disc space by a surgeon and avoiding unnecessary and excessive LF and bone removal.