J Mech Behav Biomed Mater
December 2024
Background And Objective: Different bone remodeling algorithms are used to predict bone adaptation and to understand how bones respond to the mechanical stimuli altered by implants. This paper introduces a novel micro-scale bone remodeling algorithm, which deviates from conventional methods by focusing on structure-based bone adaptation instead of density-based approaches.
Methods: The proposed model simulated cellular activities such as bone resorption, new bone formation, and maturation of newly formed bone.
An efficient functionalization of tyrosine residues in phenolic regions is achieved under metal-free conditions. The strategy involves the conversion of a tyrosine residue to 4-amino phenylalanine or 4-amino-3-methoxy phenylalanine in short peptides through a controlled oxidative dearomatization. This transformation is achieved in one pot with good yields and excellent regioselectivity.
View Article and Find Full Text PDFJ Mech Behav Biomed Mater
July 2023
Stress shielding remains a challenge in orthopaedic implants, including total hip arthroplasty. Recent development in printable porous implants offers improved patient-specific solutions by providing adequate stability and reducing stress shielding possibilities. This work presents an approach for designing patient-specific implants with inhomogeneous porosity.
View Article and Find Full Text PDFMicrowave (MW) radiation poses the risk of potential hazards on human health. The present study investigated the effects of MW 10 GHz exposure for 3 h/day for 30 days at power densities of 5.23 ± 0.
View Article and Find Full Text PDFThe difference in stiffness of a patient's bone and bone implant causes stress shielding. Thus, implants which match the stiffness of bone of the patient result in better bone growth and osseointegration. Variation in porosity is one of the methods to obtain implants with different stiffness values.
View Article and Find Full Text PDFSpinal fusion with pedicle-screw-rod is being used widely for treating spinal deformities diseases. Several biomechanical studies on screw rod based implant failure through screw pullout, bending, screw breakage have been performed. But few studies are available regarding the effect of strain for breakage of rod.
View Article and Find Full Text PDFBackground: This work uses genetic algorithm (GA) for optimum design of patient specific spinal implants (pedicle screw) with varying implant diameter and bone condition. The optimum pedicle screw fixation in terms of implant diameter is on the basis of minimum strain difference from intact (natural) to implantation at peri-prosthetic bone for the considered six different peri-implant positions.
Methods: This design problem is expressed as an optimization problem using the desirability function, where the data generated by finite element analysis is converted into an artificial neural network (ANN) model.
Currently, intervertebral disc prostheses that are designed to restore mobility to a vertebral segment are possible for the lumbar spine. The ball-and-socket joint is a constrained design, wherein the rotational axis of the intervertebral joint is forced to pass through the center of the spherical surfaces that form the joint. One advantage of ball-and-socket joints versus unconstrained designs includes better shear stability, which results in sufficient flexibility.
View Article and Find Full Text PDFBackground: Pedicle-screw-rod fixation system is very popular surgical remedy for degenerative disc disease. It is important to observe load vs. spinal motion characteristic for better understanding of clinical problems and treatment of spinal instability associated with low-back pain.
View Article and Find Full Text PDFJ Long Term Eff Med Implants
September 2016
The increasing older population is suffering from an increase in age-related spinal degeneration that causes tremendous pain. Spine injury is mostly indicated at the lumbar spine (L3-L5) and corresponding intervertebral disks. Finite element analysis (FEA) is now one of the most efficient and accepted tools used to simulate these pathological conditions in computer-assisted design (CAD) models.
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