Sagittal Alignment Differences Between Normal Subjects and Adolescent Idiopathic Scoliosis Using Vertebral Pelvic Angles.

Authors

Carlos Aleman, Thibaut Goetsch, Jeffrey Hills, Michael Patrick Kelly, Guillaume Battesti, Lucas Chomienne, Brice Ilharreborde, Mikael Finoco, Emmanuelle Ferrero, Marc Khalifé, Thierry Odent, Edouard de Charnacé, Solène Prost, Benjamin Blondel, Federico Solla, Mourad Ould-Slimane, Sébastien Pesenti, Yann Philippe Charles

Published in

Spine. Aug 19, 2026. Epub Aug 19, 2026.

Abstract

Retrospective multicenter registry study.
To compare sagittal spinopelvic alignment between normal subjects and Adolescent Idiopathic Scoliosis (AIS), to evaluate the relationship between T4 and L1 Pelvic Angles (T4PA-L1PA), including the influence of Thoracolumbar Inflection Point (TIP).
Vertebropelvic angles were described as alignment targets for normal adults, but their role remains incompletely defined in younger AIS patients.
Full-spine radiographs of 1115 normal subjects and 1779 AIS patients (10-30 y) were analyzed. AIS was classified according to Lenke. Measurements included Pelvic Incidence (PI), Pelvic Tilt (PT), segmental Thoracic Kyphosis (TK) and Lumbar Lordosis (LL), T4PA, L1PA. A Pearson correlation analyzed the relationship between parameters. TIP was categorized as cranial (above T12), junctional (T12-L1), or caudal (below L1), and T4PA-L1PA analyzed according to TIP (ANOVA). Formulae LL=0.5×PI-21 and L1PA=1.4×PI-1.7×L1PA-2 were evaluated using linear regression.
TK T1-12 was smaller <8° (P<0.001), T10-L1 <5° (P<0.001) in Lenke 1, 2 and 3 compared to normal. LL L1-L4 was larger >3° (P<0.001) in Lenke 1. L1PA differences >3° (P<0.001) existed in Lenke 1 and 2. A correlation existed between L1PA and PI (r>0.7), L1PA and PT (r>0.7), L1PA and T4PA (r>0.9) for normal and each Lenke type. T4PA-L1PA differences increased from negative to positive as the TIP moved from cranial to caudal in normal and AIS (P<0.001). Formulae for L1PA and LL calculation showed good agreement with measured values (R²>0.6).
Primary thoracic AIS had smaller TK T1-T12, TK T10-L1 and larger LL L1-L4, L1PA, while the T4-L1hip axis remained globally preserved in normal and AIS. The TIP influenced segmental alignment, with larger L1PA and smaller (negative) T4PA-L1PA differences. Vertebropelvic angles provide a reliable target for surgical planning in AIS.

PMID:
42628017
Bibliographic data and abstract were imported from PubMed on 22 Aug 2026.

Read full publication at:
Please sign in to see all details.

Stats

1-terrible, 9-excellent. How would you rate this publication? Sign in in to submit your rating.

Post a comment

You need to be signed in to post comments. You can sign in here.

Comments

There are no comments yet.