Dados do Trabalho

Título

Impact of the preoperative spinopelvic parameters on the segmental lordosis correction after one-level lateral lumbar interbody fusion

Objetivo

Our study aimed to assess whether preoperative spinopelvic parameters can increase segmental lordosis after one level of lateral lumbar interbody fusion

Metodologia

Inclusion Criteria
Patients who received LLIF surgery in our service had preoperative and
postoperative X-rays and signed a free consent form.

Patients that received anterior column realignment or have the ALL
unintentionally ruptured. Patients whose X-rays do not allow the correct
visualization and measurements of the proposed spinopelvic parameters.

The study's primary outcome was to test the correlation between spinopelvic
parameters and the gain of segmental lordosis after one level LLIF surgery.
The study's secondary goal was to assess how those Spinopelvic parameters
could influence the segmental lordosis after one level of LLIF surgery

Statistical Analysis
The data were measured using the Surgimap (Nemaris inc, Toronto, Canada)
software and compiled using Excel (Microsoft, Redmond, Washington )
software, the R software(CRAN) for the statistical analysis and graphs
elaboration.

We used the T-test or Wilcoxon Rank Sum Test to compare between groups,
depending on the sample distribution for continuous variables, and Chi-square
or Fisher exact test for discrete variables. When there were more than two
groups were performed the Kruskal-Wallis tests for nonparametric distributions
and Dunn Test method for post-hoc comparison between groups. A p-value
smaller than 0.05 was rendered as a threshold for statistical significance.

Resultados

To assess the relationship between the parameters and the gain of segmental lordosis, we performed correlation analysis. The authors found that the most correlated parameters with the Segmental Lordosis Gain were Preoperative Segmental Lordosis (-0.50) and Delta Intraoperative Lordosis (0.51).

Further, a clustering analysis was performed to identify if patients with similar characteristics could be prone to experience a higher gain of lordosis than other patients. The clusters can be explained as two groups within two subgroups each.
The first group was composed of patients with Low-Medium Pelvic Incidence (47.24 °) and subdivided into one cluster (3) with misaligned patients (PI-LL = -20.63°; PT = 27.24°) and one cluster with aligned patients (1) (PI-LL = -6.15°; PT = 11.54°). The second group composed of patients with high Pelvic Incidence (65.68°), also divided among one group (4) with misaligned parameters (PI-LL = 13.06 °; PT = 28.90 °) and one group (2) with more aligned parameters (PI-LL = 0.73°; PT = 19.62°). When comparing the segmental lordosis gain between the clusters, we could see that cluster 3 presented significantly more gain than the other cluster except from cluster 1 in the post-hoc analysis.

Conclusões

Our work shows that surgeons might use these spinopelvic parameters to plan their surgical options goals when performing one level LLIF, mainly in patients with low PI profile as they presented higher odds of loss of segmental lordosis