Abstract
Study designVariation in the biomechanical characteristics of intervertebral discs adjacent to the segment disc after undergoing percutaneous transforaminal endoscopic discectomy (PTED) in models with normal and abnormal bone mineral density (BMD) was estimated using the finite element method.ObjectiveThe study investigated the change in the incidence of adjacent segment disease (ASD) after PTED in patients without and with osteoporosis.BackgroundsPTED has been widely used for treating lumbar disc herniation (LDH); changes in BMD will affect biomechanical characteristics, possibly leading to changes in the incidence of ASD after PTED. However, this issue remains largely unclear.MethodsA non-linear, lumbosacral finite element model was reconstructed based on imaging data and validated using compared values computed by the current model from published and well-validated, in vitro biomechanical experiment studies. Corresponding PTED models with normal and abnormal BMDs were also reconstructed. Shear and von Mises stresses on the annulus fibrosis, the von Mises stress on the endplates in L5–S1 segment discs, and the total deformation of current lumbosacral models were computed in different body positions by changing loading conditions, including flexion, extension, left and right lateral bending, and axial rotation.ResultsIn most loading conditions, biomechanical characteristics of the lumbosacral segment discs with normal BMDs after PTED slightly increased. However, in the PTED model with osteoporosis, most of the biomechanical characteristics dramatically increased.ConclusionOsteoporosis leads to the deterioration of biomechanical characteristics in the adjacent segment disc after PTED; this variation may also result in an increase in the incidence of ASD. However, further studies on the interactions between pathological changes are warranted.
Highlights
adjacent segment disease (ASD) is a series of postoperative complications, including types of symptoms as low back pain (LBP) and low limb pain or numbness [1, 2]
A non-linear, lumbosacral finite element model was reconstructed based on imaging data and validated using compared values computed by the current model from published and well-validated, in vitro biomechanical experiment studies
Osteoporosis leads to the deterioration of biomechanical characteristics in the adjacent segment disc after percutaneous transforaminal endoscopic discectomy (PTED); this variation may result in an increase in the incidence of ASD
Summary
ASD is a series of postoperative complications, including types of symptoms as low back pain (LBP) and low limb pain or numbness [1, 2]. The risk factors concerning demographic data, such as senility, female sex, and obesity, as well as etiological triggers such as severe stress concentration, hypermotility, and preexisting degenerative changes in adjacent segment discs have been mentioned [1, 3,4,5,6]. While discussing the risk factors for ASD, demographic characteristics are always assumed to be defined by some biomechanical pathogenesis. Overweight patients suffer from excessive pressure in the lumbar spine, which may accelerate disc degeneration. This can explain why patients with higher body mass indices (BMI) are more prone to ASD [1, 3, 11]. Considering that disc degeneration becomes more pronounced with increasing age, we believe that senile patients always suffer from ASD because of preexisting degenerations [5, 6]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
