Planar cell polarity zebrafish models of congenital scoliosis reveal underlying defects in notochord morphogenesis.

Congenital scoliosis (CS) is a type of vertebral malformation for which the etiology remains elusive. The notochord is pivotal for vertebrae development, but its role in CS is still understudied. Here, we generated a zebrafish knockout of ptk7a, a planar cell polarity (PCP) gene that is essential for convergence and extension (C&E) of the notochord, and detected congenital scoliosis-like vertebral malformations (CVMs).

Biomechanical modeling and assessment of lumbar vertebral body tethering configurations.

Purpose: Vertebral body tethering (VBT) is a fusionless spinal growth modulation technique, which shows promise for pediatric idiopathic scoliosis (IS) curve correction. This technique, mainly used for thoracic curves, is increasingly being used to treat lumbar curves in order to preserve spine flexibility. It remains necessary to adequately define the cord tension to be applied during the operation and the instrumented levels to biomechanically predict correction over time for the lumbar spine.

Prediction of post-operative adding-on or compensatory lumbar curve correction after anterior vertebral body tethering.

Purpose: Anterior Vertebral Body Tethering (AVBT), a fusionless surgical technique based on growth modulation, aims to correct pediatric scoliosis over time. However, medium-term curvature changes of the non-instrumented distal lumbar curve remains difficult to predict. The objective was to biomechanically analyze the level below the LIV to evaluate whether adding-on or compensatory lumbar curve after AVBT can be predicted by intervertebral disc (ID) wedging and force asymmetry.

3D Radiological Outcomes and Quality of Life of Patients With Moderate Idiopathic Scoliosis Treated With Anterior Vertebral Growth Modulation Versus Bracing: Two-Year Follow-up.

Study Design: Observational cohort study.

Objective: To test the hypothesis that anterior vertebral body growth modulation (AVBGM) achieves 3D deformity correction after 2-year follow-up while brace treatment limits curve progression for moderate idiopathic scoliosis (30-50°).

Summary Of Background Data: For idiopathic scoliosis, bracing and AVBGM have overlapping indications in skeletally immature patients with moderate scoliosis curve angles, creating a grey zone in clinical practice between them.

Braces Designed Using CAD/CAM Combined or Not With Finite Element Modeling Lead to Effective Treatment and Quality of Life After 2 Years: A Randomized Controlled Trial.

Study Design: Single-center prospective randomized controlled trial.

Objective: The aim of this study was to assess the computer-aided design/manufacturing (CAD/CAM) brace design approach, with and without added finite element modeling (FEM) simulations, after 2 years in terms of clinical outcomes, 3D correction, compliance, and quality of life (QoL).

Summary Of Background Data: .

Anterior Vertebral Body Growth Modulation: Assessment of the 2-year Predictive Capability of a Patient-specific Finite-element Planning Tool and of the Growth Modulation Biomechanics.

Study Design: Numerical planning and simulation of immediate and after 2 years growth modulation effects of anterior vertebral body growth modulation (AVBGM).

Objective: The objective was to evaluate the planning tool predictive capability for immediate, 1-year, and 2-year postoperative correction and biomechanical effect on growth modulation over time.

Summary Of Background Data: AVBGM is used to treat pediatric scoliotic patients with remaining growth potential.

Contribution of Lateral Decubitus Positioning and Cable Tensioning on Immediate Correction in Anterior Vertebral Body Growth Modulation.

Study Design: Computational simulation of lateral decubitus and anterior vertebral body growth modulation (AVBGM).

Objectives: To biomechanically evaluate lateral decubitus and cable tensioning contributions on intra- and postoperative correction.

Summary Of Background Data: AVBGM is a compression-based fusionless procedure to treat progressive pediatric scoliosis.

Surgical Planning and Follow-up of Anterior Vertebral Body Growth Modulation in Pediatric Idiopathic Scoliosis Using a Patient-Specific Finite Element Model Integrating Growth Modulation.

Study Design: Numerical planning and simulation of immediate and post-two-year growth modulation effects of Anterior Vertebral Body Growth Modulation (AVBGM).

Objectives: To develop a planning tool based on a patient-specific finite element model (FEM) of pediatric scoliosis integrating growth to computationally assess the 3D biomechanical effects of AVBGM.

Summary Of Background Data: AVBGM is a recently introduced fusionless compression-based approach for pediatric scoliotic patients presenting progressive curves.

Computer-assisted design and finite element simulation of braces for the treatment of adolescent idiopathic scoliosis using a coronal plane radiograph and surface topography.

Background: Orthopedic braces made by Computer-Aided Design and Manufacturing and numerical simulation were shown to improve spinal deformities correction in adolescent idiopathic scoliosis while using less material. Simulations with BraceSim (Rodin4D, Groupe Lagarrigue, Bordeaux, France) require a sagittal radiograph, not always available. The objective was to develop an innovative modeling method based on a single coronal radiograph and surface topography, and assess the effectiveness of braces designed with this approach.

3D correction over 2years with anterior vertebral body growth modulation: A finite element analysis of screw positioning, cable tensioning and postoperative functional activities.

Background: Anterior vertebral body growth modulation is a fusionless instrumentation to correct scoliosis using growth modulation. The objective was to biomechanically assess effects of cable tensioning, screw positioning and post-operative position on tridimensional correction.

Methods: The design of experiments included two variables: cable tensioning (150/200N) and screw positioning (lateral/anterior/triangulated), computationally tested on 10 scoliotic cases using a personalized finite element model to simulate spinal instrumentation, and 2years growth modulation with the device.

3D correction of AIS in braces designed using CAD/CAM and FEM: a randomized controlled trial.

Background: Recent studies showed that finite element model (FEM) combined to CAD/CAM improves the design of braces for the conservative treatment of adolescent idiopathic scoliosis (AIS), using 2D measurements from in-brace radiographs. We aim to assess the immediate effectiveness on curve correction in all three planes of braces designed using CAD/CAM and numerical simulation compared to braces designed with CAD/CAM only.

Methods: SRS standardized criteria for bracing were followed to recruit 48 AIS patients who were randomized into two groups.

Biomechanical Assessment of Providence Nighttime Brace for the Treatment of Adolescent Idiopathic Scoliosis.

Study Design: Biomechanical study of the Providence brace for the treatment of adolescent idiopathic scoliosis (AIS).

Objectives: To model and assess the effectiveness of Providence nighttime brace.

Summary Of Background Data: Providence nighttime brace is an alternative to traditional daytime thoracolumbosacral orthosis for the treatment of moderate scoliotic deformities.

Braces Optimized With Computer-Assisted Design and Simulations Are Lighter, More Comfortable, and More Efficient Than Plaster-Cast Braces for the Treatment of Adolescent Idiopathic Scoliosis.

Study Design: Feasibility study to compare the effectiveness of 2 brace design and fabrication methods for treatment of adolescent idiopathic scoliosis: a standard plaster-cast method and a computational method combining computer-aided design and fabrication and finite element simulation.

Objectives: To improve brace design using a new brace design method.

Summary Of Background Data: Initial in-brace correction and patient's compliance to treatment are important factors for brace efficiency.