Eric Berthonnaud1,2,3, Patrice Papin4, Julie Deceuninck5, Radwan Hilmi4, Jean Claude Bernard6, Joannes Dimnet7. 1. L'Hôpital Nord Ouest Villefranche/Saône, Plateau d'Ouilly, BP 436, 69655, Villefranche/Saône cedex, France. eberthonnaud@lhopitalnordouest.fr. 2. Group of Applied Research in Orthopedic (GARO), Villefranche/Saône, France. eberthonnaud@lhopitalnordouest.fr. 3. Laboratoire de Physiologie de l'Exercice (EA4338), Université Jean Monnet, Saint-Etienne, France. eberthonnaud@lhopitalnordouest.fr. 4. L'Hôpital Nord Ouest Villefranche/Saône, Plateau d'Ouilly, BP 436, 69655, Villefranche/Saône cedex, France. 5. Laboratoire de Physiologie de l'Exercice (EA4338), Université Jean Monnet, Saint-Etienne, France. 6. Centre des Massues - Croix Rouge Française, 92 rue Edmond Locard, 69005, Lyon, France. 7. Group of Applied Research in Orthopedic (GARO), Villefranche/Saône, France.
Abstract
PURPOSE: Clinical parameters, characterizing the spinal deformations due to scoliosis, are still directly measured on the spinal curve plane projections. METHODS: A 3D spinal curve has been reconstructed from its two projections, using photogrammetric techniques. Each spinal curve is a compound of several plane regions, where it is purely flexed, and short zones of connection, where abduction and axial rotation components are concentrated. All spinal curves are represented as linear chains of regional planes articulated together. The regional plane is represented by a triangle, where one summit corresponds to the point of maximum offset. The set of weight forces, representing pelvis and spine, forms a bundle of vertical forces. The dispersion of the bundle illustrates the postural stability of patients. RESULTS AND CONCLUSIONS: The first objective was to numerically describe the changes of the 3D spinal feature, due to the correcting treatment. Changes are calculated from the comparison between 3D radiologic situations, between before and after treatment. The second objective was to determine the direction of the external force, which would be the most efficient for correcting the patient set spine/rib cage. A mild mechanical analysis is proposed, for representing the transit of the external force, from rib cage to thoracic regional plane.
PURPOSE: Clinical parameters, characterizing the spinal deformations due to scoliosis, are still directly measured on the spinal curve plane projections. METHODS: A 3D spinal curve has been reconstructed from its two projections, using photogrammetric techniques. Each spinal curve is a compound of several plane regions, where it is purely flexed, and short zones of connection, where abduction and axial rotation components are concentrated. All spinal curves are represented as linear chains of regional planes articulated together. The regional plane is represented by a triangle, where one summit corresponds to the point of maximum offset. The set of weight forces, representing pelvis and spine, forms a bundle of vertical forces. The dispersion of the bundle illustrates the postural stability of patients. RESULTS AND CONCLUSIONS: The first objective was to numerically describe the changes of the 3D spinal feature, due to the correcting treatment. Changes are calculated from the comparison between 3D radiologic situations, between before and after treatment. The second objective was to determine the direction of the external force, which would be the most efficient for correcting the patient set spine/rib cage. A mild mechanical analysis is proposed, for representing the transit of the external force, from rib cage to thoracic regional plane.
Entities:
Keywords:
3D geometric structure of deformed spines; Biplanar radiography; Correcting braces; Patient global weight; Photogrammetry; Scoliosis; Simulating the bracing effects
Authors: Ricarda Lechner; David Putzer; Dietmar Dammerer; Michael Liebensteiner; Christian Bach; Martin Thaler Journal: Int Orthop Date: 2016-12-05 Impact factor: 3.075