A morphometric analysis of all lumbar intervertebral discs and vertebral bodies in degenerative spondylolisthesis.

PURPOSE

Most morphometric studies on lumbar degenerative spondylolisthesis (DS) have focused solely on the L4-L5 slipped level, neglecting the shape of the entire lumbar segments. The purpose of this study was to present a morphometric analysis of the entire lumbar IVDs and VBs in DS.

METHODS

Out of 500 lumbar CTs, the first 100 CTs, 50 with DS at L4 and 50 age- and sex-matched control CTs, were randomly selected. All lumbar IVD and VB heights, widths, lengths and sagittal wedging as well as lumbar lordosis (LL) and sacral inclination (SI) were measured and relevant ratios calculated. The prevalence of lumbar vertebral osteophyte was also measured.

RESULTS

A total of 6700 measurements were taken. Age, height, weight and BMI had no effect on all parameters. Compared with controls, in females with DS, the majority of IVDs were flatter, with increased kyphotic wedging at L1-L2 (Δ1.3°) and L2-L3 (Δ1.8°), turning to lordotic wedging at L3-L4 (Δ5.9°), and decreased lordotic wedging at L4-L5 (Δ2.7°) and L5-S1 (Δ5.3°). The posterior IVD/VB ratio of all lumbar levels, middle IVD/VB ratio of L3-S1 and anterior IVD/VB ratio of L4-S1 were smaller. In males with DS, the L2-L3 IVD manifested more kyphotic wedging (Δ3.8°), the L4 VB wedging was more lordotic (Δ2.4°) and all L4-L5 IVD/VB ratios and L3-L4 middle and posterior IVD/VB ratios were smaller.

CONCLUSIONS

Individuals with DS have a more generalized degenerative disc disease on all lumbar vertebral levels, characterized by decreased disc space heights and kyphotic posture of the upper lumbar segments, occurring more predominantly in females than in males with DS.