Biomedical Engineering and Bioengineering Commons^™

Direct Current Electrical Stimulation Increases The Fusion Rate Of Spinal Fusion Cages, Jeffrey M. Toth, Howard Seim, Jeffrey D. Schwardt, Wendy B. Humphrey, Joel A. Wallskog, A. Simon Turner

Biomedical Engineering Faculty Research and Publications

Study Design. A randomized experimental evaluation of direct current stimulation in a validated animal model with an experimental control group, using blinded radiographic, biomechanical, histologic, and statistical measures.

Objectives. To evaluate the efficacy of the adjunctive use of direct current stimulation on the fusion rate and speed of healing of titanium interbody fusion cages packed with autograft in a sheep lumbar interbody fusion model.

Summary of Background Data. Titanium lumbar interbody spinal fusion cages have been reported to be 90% effective for single-level lumbar interbody fusion. However, fusion rates are reported to be between 70% and 80% in patients with …

Persistence Of Motor Adaptation During Constrained, Multi-Joint, Arm Movements, Robert A. Scheidt, David J. Reinkensmeyer, Michael A. Conditt, W. Zev Reymer, Ferdinando A. Mussa-Ivaldi

Biomedical Engineering Faculty Research and Publications

We studied the stability of changes in motor performance associated with adaptation to a novel dynamic environment during goal-directed movements of the dominant arm. Eleven normal, human subjects made targeted reaching movements in the horizontal plane while holding the handle of a two-joint robotic manipulator. This robot was programmed to generate a novel viscous force field that perturbed the limb perpendicular to the desired direction of movement. Following adaptation to this force field, we sought to determine the relative role of kinematic errors and dynamic criteria in promoting recovery from the adapted state. In particular, we compared kinematic and dynamic …

Micro-Ct Image-Derived Metrics Quantify Arterial Wall Distensibility Reduction In A Rat Model Of Pulmonary Hypertension, Roger H. Johnson, Kelly L. Karau, Robert C. Molthen, Steven Thomas Haworth, Christopher A. Dawson

Biomedical Engineering Faculty Research and Publications

We developed methods to quantify arterial structural and mechanical properties in excised rat lungs and applied them to investigate the distensibility decrease accompanying chronic hypoxia-induced pulmonary hypertension. Lungs of control and hypertensive (three weeks 11% O₂) animals were excised and a contrast agent introduced before micro-CT imaging with a special purpose scanner. For each lung, four 3D image data sets were obtained, each at a different intra-arterial contrast agent pressure. Vessel segment diameters and lengths were measured at all levels in the arterial tree hierarchy, and these data used to generate features sensitive to distensibility changes. Results indicate …

Control Strategies For The Transition From Multijoint To Single-Joint Arm Movements Studied Using A Simple Mechanical Constraint, Robert A. Scheidt, W. Zev Rymer

Biomedical Engineering Faculty Research and Publications

Changes were studied in neuromotor control that were evoked by constraining the motion of the elbow joint during planar, supported movements of the dominant arm in eight normal human subjects. Electromyograph (EMG) recordings from shoulder and arm muscles were used to determine whether the normal multijoint muscle activity patterns associated with reaching to a visual target were modified when the movement was reduced to a single-joint task, by pinning the elbow to a particular location in the planar work space. Three blocks of 150 movements each were used in the experiments. Subjects were presented with the unconstrained task in the …