[Design and Fabrication of Porous Implants Manufactured by 3D Printing].

Different porous structures were studied through finite element analysis and then optimal porous structure was selected for the orthopedic applications. The optimal Voronoi structure was designed and fabricated using 3D printing. The mechanical properties and osseointegration ability were both investigated.

Implant-derived magnesium induces local neuronal production of CGRP to improve bone-fracture healing in rats.

Orthopedic implants containing biodegradable magnesium have been used for fracture repair with considerable efficacy; however, the underlying mechanisms by which these implants improve fracture healing remain elusive. Here we show the formation of abundant new bone at peripheral cortical sites after intramedullary implantation of a pin containing ultrapure magnesium into the intact distal femur in rats. This response was accompanied by substantial increases of neuronal calcitonin gene-related polypeptide-α (CGRP) in both the peripheral cortex of the femur and the ipsilateral dorsal root ganglia (DRG).

3-D finite element analysis of the influence of synovial condition in sacroiliac joint on the load transmission in human pelvic system.

The anterior part of the sacroiliac joint (SIJ) is a synovial joint, with little gliding and rotary movement between the contact surfaces of SIJ during locomotion. Due to its complex structure, especially when considering the surrounding ligaments, it is difficult to construct an accurate three-dimensional (3-D) finite element model for the human pelvis. Most of the pelvic models in the previous studies were simplified with either SIJ fusing together or without the sacral bone.

[Evaluation of acetabular cup placement precision in Stryker computer-assisted navigated total hip arthroplasty].

To contrast the methodology of measuring cup placement precision utilizing Mimics and Matlab programming, based on clinical CT images of primary THA cases with computer assisted navigated surgery (CANS) and with the traditional manual method (MANS). The method was applied and analyzed to measure cup anteversion, cup abduction of 50 clinical cases with CANS and MANSThe results show that, cup placement precision differences exits between primary THA cases with CANS and MANS; more cases with CANS are within the safe zone contrasting MANS, and there was less variation and less placement error in CANS cases. CANS can improve cup placement precision and reduce the chance of dislocation efficiently.

A novel, inexpensive and easy to use tendon clamp for in vitro biomechanical testing.

Frozen clamps can hold tendons and ligaments tightly and transmit high loads, from 4 kN to 13 kN, without slippage, yet they are complex and expensive. The existing non-frozen serrated jaw clamp is simple to fabricate and use, but the maximal tensile force it can sustain is only about 2.5 kN, which is not enough in many biomechanical tests.

Timing jitter of femtosecond solitons in single-mode optical fibers: a perturbation model.

On the basis of the higher-order nonlinear Schrödinger equation, an extended soliton perturbation model is proposed. The evolution equations for the soliton parameters and the resultant expressions for timing jitter are derived. Subsequently, the model is tested to be correct in the subpicosecond-femtosecond regime through direct numerical simulations of the underlying equation by using the stochastic split-step Fourier method.