Introduction: Hip fractures are very common in Sweden. Keeping reoperation rates as low as possible is critical. One factor correlated to mechanical complications and thereby reoperation rates is the tip-apex distance. In April of 2017 the Orthopedic clinic at Karlstad’s Central Hospital in Sweden implemented new routines for the choice of treatment method of pertrocantheric and subtrocantheric femoral fractures. Aim: The primary aim of this study was to compare reoperation rates of pertrocantheric and subtrocantheric femoral fractures before and after implementation of new routines. Secondly, we wanted to study the association between the tip-apex distance and reoperation rates for pertrocantheric femoral fractures treated at Karlstad’s Central Hospital. Method: This was an internal quality control designed as a retrospective cohort study. Data on patients treated for pertrocantheric or subtrocantheric femoral fractures were retrieved from the Swedish Fracture Registry. Tip-apex distances were measured on patients’ radiographic images. P-values for comparison of the two study periods were created using the chi2 test. Association between the tip-apex distance and reoperation rate was presented as odds ratio. Result: The reoperation rates were the same for both time periods. The reoperation rates of unstable fractures were lower for the study period after implementation of new routines. Neither of these results were statistically significant. There was also no statistically significant association between the tip-apex distance and reoperation rates. Conclusion: No statistically significant decrease in reoperation rates was seen after implementation of new routines. There was no association between the tip-apex distance and reoperation rates.

The most commonly known macro scale probing devices are simply comprised of metallic leads used for measuring electrical signals. On the other hand, micromachined probing devices are realized using microfabrication techniques and are capable of providing very fine, micro/nano scale interaction with matter; along with a broad range of applications made possible by incorporating MEMS sensing and actuation techniques. Micromachined probes consist of a well-defined tip structure that determines the interaction space, and a transduction mechanism that could be used for sensing a change, imparting external stimuli or manipulating matter. Several micromachined probes intended for biological and nanotechnology applications were fabricated, characterized and tested. Probes were developed under two major categories. The first category consists of Micro Electromagnetic Probes for biological applications such as single cell, particle, droplet manipulation and neuron stimulation applications; whereas the second category targets novel Scanning Probe topologies suitable for direct nanopatterning, variable resolution scanning probe/dip-pen nanolithography, and biomechanics applications. The functionality and versatility of micromachined probes for a broad range of micro and nanotechnology applications is successfully demonstrated throughout the five different probes/applications that were studied. It is believed that, the unique advantages of precise positioning capability, confinement of interaction as determined by the probe tip geometry, and special sensor/actuator mechanisms incorporated through MEMS technologies will render micromachined probes as indispensable tools for microsystems and nanotechnology studies.