Indication Variability in Degenerative-lumbar Spine Surgery: a 4-nation survey

STUDY DESIGN: Electronic survey.

OBJECTIVE: The aim of this study was to identify the international nuances in surgical treatment patterns for severals lumbar degenerative conditions, specifically, to identify differences in responses in each country groupand different treatment trends across countries.

SUMMARY OF BACKGROUND DATA: Significant variations in treatment of lumbar degenerative conditions exist among spine surgeons, related to the lack of established consensus in the literature.

METHODS: An online survey with preformulated answers was submitted to 52 orthopedic surgeons, 50 neurosurgeons from four different countries (United States, France, Spain, and Germany) regarding five vignette-cases. Cases included: multilevel stenosis, monolevel stenosis, lytic spondylolisthesis, isthmic lysis, and degenerative scoliosis. The variability for each country was calculated according to the Index of Qualitative Variation (IQV = 0: no variability and 1: maximal variability). We used Fleiss kappa (range: from -1, poor agreement, to 1, almost perfect agreement) for assessing the reliability of agreement between the participants concerning specialties, countries, and age groups.

RESULTS: For the two stenosis cases, US surgeons were more likely to propose decompression (IQV multilevel = 0.47 and monolevel = 0.32) comparing with European countries more heterogeneous (all IQV >0.70) and more frequently proposing fusion. As regards degenerative scoliosis, all attitudes were extremely heterogeneous with IQV >0.8. Fusion for isthmic spondylolisthesis was more consensual (all IQV <0.63), but attitudes were more heterogeneous for isthmic lysis (IQV ranged from 0.48 to 0.76) with anterior approach proposed in France (37%) and United States (19.2%).The overall interrater agreement was equally slight not only for neurosurgeons (Fleiss Kappa = 0.04) and orthopedic surgeons (Kappa = 0.13), but also for countries (Kappa <0.13) and age groups (Kappa <0.1).

CONCLUSION: In this study, we found substantial agreement for some spinal conditions but a high variability in some others: intranational and international variations were observed, reflecting the lack of literature consensus.

LEVEL OF EVIDENCE: 2.