A multidirectional fracture stiffness model to determine the principal stiffness properties of a healing human tibia.

A model for the stiffness of a fractured human tibia has been developed. The model is based on Mohr's circle of inertia and relies on tibial fracture stiffness being measured in a number of planes. Using in vitro data, it has been shown that this model can be used to identify the principal stiffness values and their associated planes.

The Effects of Laser Marking and Symbol Etching on the Fatigue Life of Medical Devices.

This paper examines the question;" does permanent laser marking affect the mechanical performance of a metallic medical component?" The literature review revealed the surprising fact that very little has been presented or studied even though intuition suggests that its effect could be detrimental to a component's fatigue life. A brief investigation of laser marking suggests that defects greater than 25 μm are possible. A theoretical investigation further suggests that this is unlikely to cause issues with relation to fast fracture but is highly likely to cause fatigue life issues.

Measuring multi-dimensional, time-dependent mechanical properties of a human tibial fracture using an automated system.

This paper presents an element of a long-term research project determining a clinically quantifiable end point for fracture healing in humans. An automated loading and measurement device is presented. It has been developed as a research tool for the assessment of the mechanical properties of a healing human tibial fracture.

An automated system for measuring multi-dimensional, time dependent mechanical properties of a human tibial fracture.

An automated loading and measurement device has been developed for assessment of the mechanical properties of a healing human tibial fracture. The characteristics of the device are presented with assessments of errors. This paper constitutes a small part of a long term research project determining a clinically quantifiable end point for fracture healing in humans, hence a sample of results is presented to demonstrate the potential application of the device.

Reliability of radiographs in defining union of internally fixed fractures.

We assessed whether radiographs can predict union of internally fixed fractures, and therefore be used as end-points in studies of fracture healing. Forty-seven radiographic series of forearm, femoral and tibial fractures treated by internal fixation over a 3-year period were reviewed. All forearm fractures were treated with dynamic compression plates (DCP), and all tibial and femoral fractures with intra-medullary nails.