The Impact of the Placement of the L5 Vertebra in Relation to the Intercrest Line on the Level of Disc Herniation.

AIM: The objective of this study is to determine whether there is a correlation between a deeply situated L5 vertebra in relation to the intercrest line and the level of degeneration of the lumbar discs.

MATERIAL AND METHODS: The study comprised 152 patients who underwent surgery for lumbar disc herniation. After analyzing the radiographs, the patients were separated into two groups. The first group had an intercrest line passing via the L4 corpus, while the second group had an intercrest line passing through the L4-5 disc distance or L5 vertebra. The first group was classified as having a deeply located L5 vertebra, while the second group had a non-deeply located L5 vertebra.

RESULTS: The research discovered that male patients had a significantly higher incidence of deeply located L5 vertebra when compared to female patients (p=0.003). Patients who underwent surgery at the L4-5 level exhibited disc heights that were notably higher than those who were operated upon at the L5-S1 level. In Group-1, 68% of patients had surgery at the L4-5 level, compared to only 41.7% in Group-2 (p=0.009).

CONCLUSION: When investigating the effects of the position of the L5 vertebra on the intercrest line in relation to L4-5 and L5-S1 disc levels, the study found that the L5 vertebra being deeply located offered protection against L5-S1 disc herniation, while L4-5 disc herniation was more commonly observed in these patients. This is believed to be due to the L5-S1 segment being less mobile when the L5 vertebra is deeply located.