In recent years, research in the field of pharmaceutical sciences has led to the design of drugs for various diseases. But for the treatment of some diseases, drugs with high side effects and low efficiency are used. Designing targeted drug release systems is one of the solutions to this problem. These systems can deliver a controlled amount of drug to the target cell or tissue. In this paper, drug release was simulated in a screw model designed in Comsol software for orthopedic applications. The purpose of this simulation is to investigate the distribution of the drug concentration on the screw in the surrounding chamber over time. To simulate drug release in a fluid, Navier-Stokes equations for incompressible fluid are used for fluid velocity and pressure, as well as mass transfer equations for the drug concentration distribution. A tetrahedral mesh is used for meshing the model. This simulation is performed in a time-dependent manner for 72 hours with time steps of 0.1 hours. The equations have been solved directly with the PARDISO solver. The obtained results show that drug distribution changes exponentially. As can be seen, the first release of the drug was incremental to 50 hours, and after the release amount, it reached a constant and maximum value. تفاصيل المقالة

One of the main problems in sports medicine in today’s world is knee injuries. Champions of various sports fields often suffer from common knee injuries, such as injuries to the anterior cruciate ligament, middle cruciate ligament, medial collateral ligament of the knee, or meniscus. In this paper, a knee brace for general applications is modeled and its stress and strain analysis is calculated with the help of software. First, the displacement of the knee brace with ABAQUS software is investigated. By moving toward the top of the knee brace, the amount of displacement decreases. So that at least the amount of displacement is in the upper part of the knee brace. In the next part, the amount of strain and strain for this knee brace is investigated. The amount of stress in the upper part of the knee brace is higher than in other places. Additionally, the amount of strain for this knee brace is determined, the knee brace in the upper part, on the inner side of the knee brace, bears more strain. The results show that this knee brace can be easily produced and considered for different applications. تفاصيل المقالة