Comparison of axial-rotational postoperative periprosthetic fracture of the femur in composite osteoporotic femur versus human cadaveric specimens: A validation study.

Postoperative periprosthetic femoral fracture following hip replacement has been the subject of many varied experimental approaches. Cadaveric samples offer realistic fit and fracture patterns but are subject to large between-sample variation. Composite femurs have not yet been validated for this purpose.

Calcar-collar contact during simulated periprosthetic femoral fractures increases resistance to fracture and depends on the initial separation on implantation: A composite femur in vitro study.

Background: A calcar collar may reduce risk of periprosthetic fracture of the femur, through collar contact. We estimated the effect of collar contact on periprosthetic fracture mechanics using a collared fully coated cementless femoral stem and then estimated the effect of initial calcar-collar separation on the likelihood of collar contact.

Methods: Three groups of six composite left femurs with increasing calcar-collar separation in each group, underwent periprosthetic fracture simulation in a materials testing machine.

Mechanical behaviour of biodegradable AZ31 magnesium alloy after long term in vitro degradation.

Biodegradable magnesium alloys including AZ31 are exciting candidates for temporary implants as they eliminate the requirement for surgical removal, yet have higher mechanical properties than degradable polymers. However, the very long term mechanical properties and degradation of these alloys have not been fully characterized. The tensile, bending and corrosion behaviour of biodegradable AZ31 Mg alloy specimens have been investigated for up to 9months in vitro in phosphate buffered saline (PBS).

An in vitro scratch tendon tissue injury model: effects of high frequency low magnitude loading.

The healing process of ruptured tendons is suboptimal, taking months to achieve tissue with inferior properties to healthy tendon. Mechanical loading has been shown to positively influence tendon healing. However, high frequency low magnitude (HFLM) loads, which have shown promise in maintaining healthy tendon properties, have not been studied with in vitro injury models.

A novel in vitro loading system for high frequency loading of cultured tendon fascicles.

Tendons are known to adapt to their mechanical environment, however high frequency low magnitude (HFLM) loading regimes (10-50Hz), which are effective in promoting bone anabolic effects, have not been investigated in controlled conditions in tendon. In vitro loading systems (IVLS) enable precise characterisation of the link between their controlled mechanical environment and cultured tissue biological response. We report a novel IVLS design using an applied magnetic field to produce time varying loading in cultured rat tail tendon fascicles (RTTF).