To compare the mechanical effectiveness of a new conical screw design with a conventional cylindrical screw design, the screw insertion time, torque, and pull-out strength of single-pedicle screw and triangulated-pedicle screw constructs of each type of screw were compared in human cadaveric vertebral bodies. The time required to insert the conical screws was less than that required for cylindr...

STUDY DESIGN Pedicle screw strength or load to failure was biomechanically evaluated, and the geometric characteristics of pedicle screw instrumentation systems were compared. OBJECTIVES To compare the features of pedicle screw systems, and to demonstrate the failure point of the polyaxial pedicle screw head. SUMMARY OF BACKGROUND DATA Many pedicle screw instrumentation systems are currentl...

Compounds are generally acknowledged to be formed by at least two words (e.g. Eng. taxi-driver, postman, It. divano-letto ‘sofa-bed’, camposanto ‘cemetery’, Fr. tire bouchon ‘cork-screw’, timbre-poste ‘stamp’, etc.). Though this definition does not always hold true, it is nonetheless descriptively valid for the core of compounding processes. Since we have reasons to believe that the classificat...

The rotary inverted pendulum system was a highly nonlinear model, multivariable and absolutely unstable dynamic system. This paper presents hybrid control method for swing up and LQR control method for the stabilization. The flexibility of the hybrid control method based on the selection of heuristic swing up controller and energy swing up controller at the different positions of pendulum. The ...

Unlike classification, position labels cannot be assigned manually by humans. For this reason, generating supervision for precise object localization is a hard task. This paper details a method to create large datasets for 3D object localization, with real world images, using an industrial robot to generate position labels. By knowledge of the geometry of the robot, we are able to automatically...

Like a power driver for which the bit can be changed for each screw that is turned, improvement of brain protection strategies and the development of hybrid techniques have provided us with the ability to offer tailored repair options for patients with complex thoracic disease involving the arch. Variations of the frozen elephant trunk operation have been the most versatile of the newer hybrid ...

Experimental results from a statistical analysis algorithm for objectively comparing toolmarks via data files obtained using optical profilometry data are described. The algorithm employed has successfully been used to compare striated marks produced by screwdrivers. In this study, quasi-striated marks produced by the cutting surfaces of slip-joint pliers were examined. Marks were made by cutti...

The aim of this study was to compare the interfragmentary compression generated across a simulated femoral fracture model by a conventional 4.5 mm AO/ASIF cortical lag screw with a differentially pitched cortical compression screw. A 45-degree osteotomy was made in a whole bone composite femoral shaft, this was internally fixed with either a conventional 4.5 mm AO/ASIF cortical lag screw or the...

BACKGROUND Efforts to select the appropriate number of implants in adolescent idiopathic scoliosis (AIS) instrumentation are hampered by a lack of biomechanical studies. The objective was to biomechanically evaluate screw density at different regions in the curve for AIS correction to test the hypothesis that alternative screw patterns do not compromise anticipated correction in AIS when using ...

there have been a number of developments in screw design and implantation techniques over recent years, including proposal of an alternative trajectory entitled as cortical bone trajectory (cbt). cortical bone trajectory has been investigated in recent medical treatments as an alternative for screw fixation aimed at increasing purchase of pedicle screws in higher density bone. cbt screw inserti...