Biomedical Engineering and Bioengineering Commons^™

Difference In Bioimpedance Across The Knee In Un-Injured Young Adults, Patrick J. Atkinson, Theresa Atkinson, Allison Seeley, Seerut Dhillon

Mechanical Engineering Publications

Background

Knee injuries induce swelling and resolution of swelling may be a useful factor in identifying states of healing and time to return to sports activities. Recent work has suggested that bioimpedance can provide an objective measure of swelling following total knee arthroplasty (TKA) and therefore may also provide guidance for clinical decision-making following knee injury. This study measures knee bioimpedance in young, active people to help define baseline variability and factors that influence limb to limb differences.

Methods

Bioimpedance was measured via sensors placed at the foot/ankle and thigh, in positions similar to those suggested for monitoring post-TKA swelling. …

Quantum Chemistry Calculations For Metabolomics, Susanta K. Das, Ricardo M. Borges, Sean M. Colby, Arthur S. Edison, Oliver Fiehn, Tobias Kind, Jesi Lee, Amy T. Merrill, Kenneth M. Merz Jr., Thomas O. Metz, Jamie R. Nunez, Dean J. Tantillo, Lee-Ping Wang, Shunyang Wang, Ryan S. Renslow

Mechanical Engineering Publications

A primary goal of metabolomics studies is to fully characterize the small-molecule composition of complex biological and environmental samples. However, despite advances in analytical technologies over the past two decades, the majority of small molecules in complex samples are not readily identifiable due to the immense structural and chemical diversity present within the metabolome. Current gold-standard identification methods rely on reference libraries built using authentic chemical materials (“standards”), which are not available for most molecules. Computational quantum chemistry methods, which can be used to calculate chemical properties that are then measured by analytical platforms, offer an alternative route for building …

Optimizing Hybrid Plate Fixation With A Locked, Oblique End Screw In Osteoporotic Fractures, Patrick Atkinson, Aaron Wynkoop, Osy Ndubaku, Paul M. Charpentier, Jeffrey B. Peck, Norman E. Walter

Mechanical Engineering Publications

Background

The end screw in a fracture plate creates the greatest resistance to bending. For osteoporotic fractures treated with plates, there is some question as to the optimal screw insertion technique for the screw farthest from the fracture. A locked, oblique end screw was previously shown to increase resistance to periprosthetic fracture. It is unknown, however, how this end screw configuration would resist pullout when subjected to bending.

Methods

Narrow, low contact 3.5 mm locking compression plates with 6 and 12 holes were anchored to simulated bone material with material properties representing osteoporotic bone. Four configurations were evaluated for the …

Biomechanical Performance Of Variable And Fixed Angle Locked Volar Plates For The Dorsally Comminuted Distal Radius, Patrick Atkinson, D. Martineau, J. Shorez, C. Beran, A. G. Dass

Mechanical Engineering Publications

Background

The ideal treatment strategy for the dorsally comminuted distal radius fracture continues to evolve. Newer plate designs allow for variable axis screw placement while maintaining the advantages of locked technology. The purpose of this study is to compare the biomechanical properties of one variable axis plate with two traditional locked constructs.

Methods

Simulated fractures were created via a distal 1 cm dorsal wedge osteotomy in radius bone analogs. The analogs were of low stiffness and rigidity to create a worst-case strength condition for the subject radius plates. This fracture-gap model was fixated using one of three different locked volar …

A Method To Modify Angle-Stable Intramedullary Nail Construct Compliance, Patrick Atkinson, B. P. Flanagan, D. Lecronier, M. R. Kubacki, P. Telehowski

Mechanical Engineering Publications

Traditional interlocked intramedullary (IM) nails have recently been modified to provide enhanced angular stability. These so-called ‘angle-stable’ IM nails are designed to eliminate construct toggle and also provide increased axial, bending, and torsional stiffness. While this added stability is needed for small fracture gaps to heal, angle-stable nails may be too stiff for large fracture gaps to unite. Even though relative stability is recommended for large fracture gaps, recent in vivo data indicates that traditional nails may allow for too much motion for healing to occur. The current study evaluated a modified technique for implanting an angle-stable nail which allows …

Orthogonal Linear Regression In Roentgen Stereophotogrammetry, Patrick Atkinson, Jesse V. Benny, Brian J. Mccartin

Mechanical Engineering Publications

Rooted in aerial reconnaissance, mathematical photogrammetry has evolved into a mainstay of biomedical image processing. The present paper develops an algorithm for Roentgen stereophotogrammetry, a method of imaging musculoskeletal systems both static and dynamic, which incorporates a number of novel features employing techniques from projective geometry, orthogonal regression and least squares approximation. Theoretical and numerical evidence is presented of the efficacy of the proposed procedure.