High-grade L5-S1 spondylolisthesis with lumbosacral kyphosis: Long-term results of non-instrumented circumferential arthrodesis in children, adolescents.

Introduction: The choice of surgical technique for high-grade spondylolisthesis (HGS) associated with lumbosacral kyphosis remains controversial. Are non-instrumented techniques still relevant, what with the multiplicity and modernity of patient-specific instrumentation?

Hypothesis: Our hypothesis was that a non-instrumented circumferential arthrodesis performed after a period of gradual reduction of HGS, associated with lumbosacral kyphosis, provided satisfactory long-term functional and radiographic results in children and adolescents while minimizing the risk of complications.

Materials And Methods: Thirty-one L5-S1 HGS associated with a lumbosacral kyphosis operated by non-instrumented circumferential arthrodesis after a period of traction and suspension were included in our study. The first stage of this technique consisted of a gradual reduction using traction followed by immobilization in the corrected position. The second stage involved a posterior, followed by an anterior, surgical procedure and a spica cast immobilization for 4 months. The mean age at surgery was 13.9±2.3 years (6-18) and the mean follow-up was 10.3±4.5 years (2.1-17.8).

Results: The overall complication rate was 26% (n=8/31): 13% neurologic complications, 10% bone fusion defects and 3% skin complications. The reoperation rate was 13% (n=4/31). The mean ODI (/50) was 3±4.6 (0-22) and the SRS-30 126.7±15 (72-143). The Taillard index decreased by 25% (p<.001) and remained stable throughout the follow-up period (p=.65). The lumbosacral angle was corrected by 13.5% (p=.03) and the correction was maintained throughout the follow-up period (p=.71). At the last follow-up, the lumbosacral angle was significantly correlated with a low ODI score and a high SRS-30 score (p<.05).

Conclusion: Even though this technique achieved a smaller reduction of the lumbosacral angle, it reduced by at least a factor of three the incidence of neurologic complications and resulted in satisfactory functional outcomes when compared to instrumented and intraoperative correction series.

Level Of Evidence: IV.