Development of a Detailed Volumetric Finite Element Model of the Spine to Simulate Surgical Correction of Spinal Deformities

Abstract

A large spectrum of medical devices exists; it aims to correct deformities associated with spinal disorders. The development of a detailed volumetric finite element model of the osteoligamentous spine would serve as a valuable tool to assess, compare, and optimize spinal devices. Thus the purpose of the study was to develop and initiate validation of a detailed osteoligamentous finite element model of the spine with simulated correction from spinal instrumentation. A finite element of the spine from T1 to L5 was developed using properties and geometry from the published literature and patient data. Spinal instrumentation, consisting of segmental translation of a scoliotic spine, was emulated. Postoperative patient and relevant published data of intervertebral disc stress, screw/vertebra pullout forces, and spinal profiles was used to evaluate the models validity. Intervertebral disc and vertebral reaction stresses respected published in vivo, ex vivo, and in silico values. Screw/vertebra reaction forces agreed with accepted pullout threshold values. Cobb angle measurements of spinal deformity following simulated surgical instrumentation corroborated with patient data. This computational biomechanical analysis validated a detailed volumetric spine model. Future studies seek to exploit the model to explore the performance of corrective spinal devices.

A Study of the Dynamic Anterior Cervical Plate Implant by Computer Aided Virtual Engineering Method

“…The simulations were more precise and reproducible than those in cadaver models [15]. Nevertheless, the experiment outcomes cannot predict the actual situation of in vivo application of the modified DACBP system.…”

Computational modelling of the scoliotic spine: A literature review

“…Many scoliotic models are validated by simulating the surgical intervention performed and then comparing predicted curvature to the post‐operative curvature 13 , 15 , 70 , 72 , 73 , 74 , 81 , 84 , 106 , 127 , 128 , 129 , 131 , 132 , 133 , 139 or by simulating a bending test and comparing the predicted curvature to the measured curvature from radiographic images. 69 , 85 , 96 , 134 , 135 , 136 , 137 , 140 Predicted Cobb angles within 5° of the clinically measured values are often predicted and are considered acceptable as it corresponds to the clinical accuracy.…”

“…In vivo, in vitro, and/or in silico literature data has been used for validation. Model predictions are compared to the reported RoM, 68 , 78 , 79 , 97 , 119 muscle activation 142 or force, 130 IDP, 73 , 105 , 130 screw pull out forces, 73 loads on the vertebrae, 88 shear stresses within the IVD, 105 and IVD stiffness. 67 These parameters have been compared to the values reported in literature, sometimes to a single data set from literature and the standard deviation on that data if it is available.…”

Computer-Assisted Orthopedic Surgery: Current State and Future Perspective

“…For example, a large spectrum of medical devices exists for correcting deformities associated with spinal disorders. Driscoll et al ( 81 ) developed a detailed volumetric finite element model of the spine to simulate surgical correction of spinal deformities and to assess, compare, and optimize spinal devices. Another example was presented in Ref.…”