Sharif Digital Repository

Motorized intramedullary nails are a viable solution to treat patients with limb-length inequality. These fully implanted devices use external magnetic actuation to extend. This research examines the conceptual design of this type of nails by investigating various ideas and previous designs. The implant mechanism, body and controller are designed in detail. It was then simulated in standard tests to evaluate it. In addition, the implanted nail undergoes a biomechanical analysis and its stiffness is assessed. Finally, the controller design is carried out using dipole magnetic theory and verified by finite element simulations. As a proof of concept, we made a prototype that is twice the size... 

Intramedullary nailing procedure is one of the common methods for fixing the fracture of long bones, in which after reduction of a fractured bone and opening up the bone medullary cavity with a drill and metal wire, the surgeon inserts the rod into the bone with continuous strikes. The rod is then tighten to the bone sing the locking screws on the two ends. The mechanical stability of fracture fixation against shear and rotary movement of the two broken parts is essential for the process of repair and fracture treatment. This stability depends on several factors including the difference curvature of the rod and the bone, the bar diameter, the cross-sectional area of the rod, and the function... 

Fractures of the shaft of the long bones-especially in femur and tibia- is one of the most common fractures. In past decades various methods have been suggested for induction, fixation and repair of these fractures. The main fixation method for shaft fractures of femur and tibia in adult patients is named “Intramedullary Nailing”. In this method, after inducing the fracture, the bone marrow is pulled out via a hole created in the proximal part of the bone. Then, a nail will go down through this empty space inside the bone. This nail will be fixed in to proximal and distal parts of fractures with some locking screws. This way, the part of fracture cannot move respect to each other and the... 

Soil nailing is a method of in situ reinforcement utilizing passive inclusions. It can be used to retain excavations and stabilize slopes by creating in situ, reinforced, soil retaining structures. This method has been used widely in recent years. Construction of a soil nail wall is performed in vertical steps, with construction starting at the top of the excavation and proceeding down. Once an excavated step is reinforced with soil nails, a permanent or temporary facing is then applied to retain the soil. Stepped soil nail wall is formed by setting a platform in the middle part of a typical soil nail wall.In this Thesis, behavior of a soil nail wall and a stepped soil nail wall are studied... 

Soil nailing is an in-situ technique of mechanically stabilizing soil masses which has been used in France, Germany, United states, and recently in Iran. A review of literature shows that Soil-Nailed walls have performed well during strong ground motions in comparison with the gravity retaining structures. After the 1989 Loma Prieta earthquake, minor signs of distress or corresponding deformation were found on the Soil-Nailed walls, indicating excellent performance of such structures during moderate and strong shakings. These observations indicate that Soil-Nailed walls have an inherent satisfactory seismic response. This has been attributed to the intrinsic flexibility of the Soil-Nailed...