Skip Navigation LinksHome > January 2014 - Volume 74 - Issue 1 > The Comprehensive Anatomical Spinal Osteotomy Classification
doi: 10.1227/NEU.0000000000000182o
Research-Laboratory:Editor' Choice

The Comprehensive Anatomical Spinal Osteotomy Classification

Schwab, Frank MD*; Blondel, Benjamin MD*,‡; Chay, Edward BA*; Demakakos, Jason MS*; Lenke, Lawrence MD§; Tropiano, Patrick MD; Ames, Christopher MD; Smith, Justin S. MD, PhD; Shaffrey, Christopher I. MD; Glassman, Steven MD#; Farcy, Jean-Pierre MD**; Lafage, Virginie PhD*

Editor's Choice
Collapse Box


BACKGROUND: Global sagittal malalignment is significantly correlated with health-related quality-of-life scores in the setting of spinal deformity. In order to address rigid deformity patterns, the use of spinal osteotomies has seen a substantial increase. Unfortunately, variations of established techniques and hybrid combinations of osteotomies have made comparisons of outcomes difficult.

OBJECTIVE: To propose a classification system of anatomically-based spinal osteotomies and provide a common language among spine specialists.

METHODS: The proposed classification system is based on 6 anatomic grades of resection (1 through 6) corresponding to the extent of bone resection and increasing degree of destabilizing potential. In addition, a surgical approach modifier is added (posterior approach or combined anterior and posterior approaches). Reliability of the classification system was evaluated by an analysis of 16 clinical cases, rated 2 times by 8 different readers, and calculation of Fleiss kappa coefficients.

RESULTS: Intraobserver reliability was classified as “almost perfect”; Fleiss kappa coefficient averaged 0.96 (range, 0.92-1.0) for resection type and 0.90 (0.71-1.0) for the approach modifier. Results from the interobserver reliability for the classification were 0.96 for resection type and 0.88 for the approach modifier.

CONCLUSION: This proposed anatomically based classification system provides a consistent description of the various osteotomies performed in spinal deformity correction surgery. The reliability study confirmed that the classification is simple and consistent. Further development of its use will provide a common frame for osteotomy assessment and permit comparative analysis of different treatments.

ABBREVIATIONS: P, posterior approach

A/P, combined anterior and posterior approaches

PSO, pedicle subtraction osteotomy

Copyright © by the Congress of Neurological Surgeons


Article Tools


Article Level Metrics

Search for Similar Articles
You may search for similar articles that contain these same keywords or you may modify the keyword list to augment your search.