Background: We sought to characterize humeral-sided radiographic changes at a minimum of 2 years after reverseshoulder arthroplasty (RSA) to determine their association with specific implantation techniques.Methods: The immediate and most recent postoperative anteroposterior radiographs of 120 shoulders with primary RSAand a minimum of 2-years of radiographic follow-up were an...

Stress shielding and bone remodeling effects are critical issues in promoting long term stability of Total Hip Arthroplasty (THA). Stress shielding occurs when the femur experiences less stress after the presence of the prosthesis stem. In this study, biomechanical evaluations of lower limbs are established using the finite element method in corresponding to stress distributions. Lower limbs CT...

BACKGROUND Femoral bone remodeling in response to stress shielding induces periprosthetic bone loss. Computerized finite element analysis (FEA) is employed to demonstrate differences in initial stress distribution. However, FEA is often performed without considering the precise sites at which the stem was fixed. We determined whether FEA reflects mid-term radiological examination exactly as pre...

BACKGROUND The efficacy of dynamic anterior cervical plates is somewhat controversial. Screws in static-plate designs have a smaller diameter and can cut through bone under load. While not ideal, this unintended loosening can help mitigate stress shielding. Stand-alone interbody devices with integral fixation have large endplate contact areas that may inhibit or prevent loosening of the fixatio...

OBJECTIVE The study aims to compare the stress shielding effects of implantable anatomical and traditional prostheses after in vitro total hip joint replacement simulation. The study serves as a biomechanical basis for novel artificial prostheses and for clinical hip joint replacements. METHODS Sixteen femoral specimens from adult male corpses were randomly divided into two groups: the tradit...

BACKGROUND In the internal fixation of fractured bone by means of bone-plates fastened to the bone on its tensile surface, an on-going concern has been the excessive stress-shielding of the bone by the excessively-stiff stainless-steel plate. The compressive stress-shielding at the fracture-interface immediately after fracture-fixation delays callus formation and bone healing. Likewise, the ten...

Finite-element analysis was used to study the general differences in load-transfer mechanisms and stress patterns of cemented, fully ingrown, proximally ingrown, and smooth press-fitted femoral stems in total hip arthroplasty (THA). Identical stems were used for the noncemented configurations and a similar stem shape for the cemented configurations. In each model, bone properties and loading ch...

In this review I report evidence that the mainstream field of oxidative damage biology has been running fast in the wrong direction for more than 50 years. Reactive oxygen species (ROS) and chronic oxidative changes in membrane lipids and proteins found in many chronic diseases are not the result of accidental damage. Instead, these changes are the result of a highly evolved, stereotyped, and p...

When these patients are supplied with stronger implants to improve the fracture stability, it is feared that stress-shielding occurs. Stress-shielding is the effect when the load on the bone decreases and the load on the implant increases, because of the high stiffness of the implant. Especially reinforced intramedullary nails bear the risk of a shift of the failure mode from the nail to the la...

We implanted titanium and carbon fibre-reinforced plastic (CFRP) femoral prostheses of the same dimensions into five prosthetic femora. An abductor jig was attached and a 1 kN load applied. This was repeated with five control femora. Digital image correlation was used to give a detailed two-dimensional strain map of the medial cortex of the proximal femur. Both implants caused stress shielding ...