Segmental Contributions to Lumbar Lordosis: A Computed Tomography Study

Area of Science:

• Spine biomechanics
• Radiographic analysis
• Lumbar spine anatomy

Background:

• Lumbar lordosis is crucial for spinal alignment.
• Understanding segmental contributions to lordosis is important.
• Pelvic incidence (PI) influences spinal curvature.

Purpose of the Study:

• Determine individual vertebral body lordosis contribution to overall lumbar lordosis.
• Establish the relationship between vertebral body lordosis and pelvic incidence (PI).

Main Methods:

• Computed tomography (CT) scans of 102 patients without radiographic disease were analyzed.
• Pelvic incidence (PI) and segmental lordosis (bone and disc) from L1 to sacrum were measured.
• Correlative analysis and ANOVA were used to assess contributions.

Main Results:

• Mean total bony lordosis was 10.8°, mean total disc lordosis was 36.3°.
• Significant differences in bony lordosis were found across PI strata (P < .001).
• Distal lordosis comprised 80.8% of total lordosis; proximal bone contribution was greater with increasing PI.

Conclusions:

• Vertebral body contribution to lordosis is greater in the proximal lumbar spine as PI increases.
• Low PI can lead to reduced proximal vertebral body lordosis, sometimes resulting in kyphosis.
• Segmental analysis of spinal alignment is recommended over global analysis for future research.