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Published in: European Spine Journal 9/2014

01-09-2014 | Original Article

Development of appropriateness criteria for the surgical treatment of symptomatic lumbar degenerative spondylolisthesis (LDS)

Authors: A. F. Mannion, V. Pittet, F. Steiger, J.-P. Vader, H.-J. Becker, F. Porchet, The Zürich Appropriateness of Spine Surgery (ZASS) Group

Published in: European Spine Journal | Issue 9/2014

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Abstract

Purpose

Spine surgery rates are increasing worldwide. Treatment failures are often attributed to poor patient selection and inappropriate treatment, but for many spinal disorders there is little consensus on the precise indications for surgery. With an aging population, more patients with lumbar degenerative spondylolisthesis (LDS) will present for surgery. The aim of this study was to develop criteria for the appropriateness of surgery in symptomatic LDS.

Methods

A systematic review was carried out to summarize the current level of evidence for the treatment of LDS. Clinical scenarios were generated comprising combinations of signs and symptoms in LDS and other relevant variables. Based on the systematic review and their own clinical experience, twelve multidisciplinary international experts rated each scenario on a 9-point scale (1 highly inappropriate, 9 highly appropriate) with respect to performing decompression only, fusion, and instrumented fusion. Surgery for each theoretical scenario was classified as appropriate, inappropriate, or uncertain based on the median ratings and disagreement in the ratings.

Results

744 hypothetical scenarios were generated; overall, surgery (of some type) was rated appropriate in 27 %, uncertain in 41 % and inappropriate in 31 %. Frank panel disagreement was low (7 % scenarios). Face validity was shown by the logical relationship between each variable’s subcategories and the appropriateness ratings, e.g., no/mild disability had a mean appropriateness rating of 2.3 ± 1.5, whereas the rating for moderate disability was 5.0 ± 1.6 and for severe disability, 6.6 ± 1.6. Similarly, the average rating for no/minimal neurological abnormality was 2.3 ± 1.5, increasing to 4.3 ± 2.4 for moderate and 5.9 ± 1.7 for severe abnormality. The three variables most likely (p < 0.0001) to be components of scenarios rated “appropriate” were: severe disability, no yellow flags, and severe neurological deficit.

Conclusion

This is the first study to report criteria for determining candidacy for surgery in LDS developed by a multidisciplinary international panel using a validated method (RAM). The panel ratings followed logical clinical rationale, indicating good face validity. The work refines clinical classification and the phenotype of degenerative spondylolisthesis. The predictive validity of the criteria should be evaluated prospectively to examine whether patients treated “appropriately” have better clinical outcomes.
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Metadata
Title
Development of appropriateness criteria for the surgical treatment of symptomatic lumbar degenerative spondylolisthesis (LDS)
Authors
A. F. Mannion
V. Pittet
F. Steiger
J.-P. Vader
H.-J. Becker
F. Porchet
The Zürich Appropriateness of Spine Surgery (ZASS) Group
Publication date
01-09-2014
Publisher
Springer Berlin Heidelberg
Published in
European Spine Journal / Issue 9/2014
Print ISSN: 0940-6719
Electronic ISSN: 1432-0932
DOI
https://doi.org/10.1007/s00586-014-3284-0

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