K Abelin-Genevois1, D Sassi2, S Verdun3, P Roussouly2. 1. Department of Spine Surgery, Centre Medico Chirurgical et de Réadaptation des Massues, Croix Rouge Francaise, 92 rue Edmond Locard, 69322, Lyon Cedex 05, France. kgenevois@gmail.com. 2. Department of Spine Surgery, Centre Medico Chirurgical et de Réadaptation des Massues, Croix Rouge Francaise, 92 rue Edmond Locard, 69322, Lyon Cedex 05, France. 3. Departement of Medical Research, Groupement des Hôpitaux de l'Institut Catholique de Lille, Hôpital Saint Philibert, Lomme Cedex, France.
Abstract
INTRODUCTION: Surgical treatment of AIS aims to correct the coronal and sagittal alignment of the spine. The global alignment of the spine may be normalized through reciprocal changes between the fused spine and adjacent segments. We propose a new classification system describing the specific sagittal patterns induced by AIS to define reproducible guidelines for the surgical strategy. METHODS: We analyzed 100 consecutive AIS patients aged between 12 and 18 years candidate for spinal fusion. The following parameters were measured and compared for each pattern: spino-pelvic parameters, magnitude and length of the lumbar sagittal angle, magnitude and length of the thoracic sagittal angles (T1T12 and T4T12 angles, TKmax), T10 L2 angle, C7 slope and C2C7 angle. RESULTS: Three parameters strongly differentiated the four patterns: thoracic sagittal angles (T1T12 and T4T12 angles, TKmax), T10 L2 angle and C7 slope. Less than half of the patients (44%) had a normal sagittal shape. Within, Type 2 characterized by thoracic hypokyphosis, Type 2a (thoracic hypokyphosis) were mostly Lenke type 1 or 2 curves, and type 2b (thoracic hypokyphosis with TL kyphosis) occurred specifically in double major or TL/L curves. Type 3 were two-curve sagittal shape with cervicothoracic kyphosis and TL lordosis (9%), mainly in Lenke 1 curves. DISCUSSION: This new classification summarizes all the pathological scenarios of the sagittal alignment of AIS into four patterns. A specific surgical planning can be extrapolated for each pattern. In type 1, the objective is to preserve the sagittal shape. In type 2, the objective is to restore thoracic kyphosis. In type 2b, TL junction should be straightened. In type 3, the objective is to reshape the lower arc of thoracic sagittal angle and straighten the TL junction. These slides can be retrieved under Electronic Supplementary Material.
INTRODUCTION: Surgical treatment of AIS aims to correct the coronal and sagittal alignment of the spine. The global alignment of the spine may be normalized through reciprocal changes between the fused spine and adjacent segments. We propose a new classification system describing the specific sagittal patterns induced by AIS to define reproducible guidelines for the surgical strategy. METHODS: We analyzed 100 consecutive AIS patients aged between 12 and 18 years candidate for spinal fusion. The following parameters were measured and compared for each pattern: spino-pelvic parameters, magnitude and length of the lumbar sagittal angle, magnitude and length of the thoracic sagittal angles (T1T12 and T4T12 angles, TKmax), T10 L2 angle, C7 slope and C2C7 angle. RESULTS: Three parameters strongly differentiated the four patterns: thoracic sagittal angles (T1T12 and T4T12 angles, TKmax), T10 L2 angle and C7 slope. Less than half of the patients (44%) had a normal sagittal shape. Within, Type 2 characterized by thoracic hypokyphosis, Type 2a (thoracic hypokyphosis) were mostly Lenke type 1 or 2 curves, and type 2b (thoracic hypokyphosis with TL kyphosis) occurred specifically in double major or TL/L curves. Type 3 were two-curve sagittal shape with cervicothoracic kyphosis and TL lordosis (9%), mainly in Lenke 1 curves. DISCUSSION: This new classification summarizes all the pathological scenarios of the sagittal alignment of AIS into four patterns. A specific surgical planning can be extrapolated for each pattern. In type 1, the objective is to preserve the sagittal shape. In type 2, the objective is to restore thoracic kyphosis. In type 2b, TL junction should be straightened. In type 3, the objective is to reshape the lower arc of thoracic sagittal angle and straighten the TL junction. These slides can be retrieved under Electronic Supplementary Material.
Authors: Takashi Fujishiro; Louis Boissière; Derek Thomas Cawley; Daniel Larrieu; Olivier Gille; Jean-Marc Vital; Ferran Pellisé; Francisco Javier Sanchez Pérez-Grueso; Frank Kleinstück; Emre Acaroglu; Ahmet Alanay; Ibrahim Obeid Journal: Eur Spine J Date: 2019-03-07 Impact factor: 3.134
Authors: Tom P Schlösser; Kariman Abelin-Genevois; Jelle Homans; Saba Pasha; Moyo Kruyt; Pierre Roussouly; Suken A Shah; René M Castelein Journal: Eur Spine J Date: 2020-12-23 Impact factor: 3.134
Authors: Tom P C Schlösser; René M Castelein; Pierre Grobost; Suken A Shah; Kariman Abelin-Genevois Journal: Eur Spine J Date: 2021-02-27 Impact factor: 3.134
Authors: Alice Baroncini; Aurelien Courvoisier; Pedro Berjano; Filippo Migliorini; Jörg Eschweiler; Philipp Kobbe; Frank Hildebrand; Per David Trobisch Journal: Eur Spine J Date: 2021-12-15 Impact factor: 3.134