A Cost-Effective Upper Extremity Prosthesis Design

Upper extremity prostheses are a scarce necessity in less developed countries due to the lack of medical facilities, economic resources, and prevalent warfare. Prostheses have become a growing need as fifty-thousand amputations occur annually, with the current market being focused primarily on lower extremities. Leg prostheses have received much more attention and success than their upper extremity counterparts, due to their lower complexity that also yields lower cost. Prosthetic legs only need to fulfill basic motions such as walking and running, as opposed to the more complicated hands that encompass 22 degrees of motion. In less developed countries with few medical facilities, amputees need to travel long distances to find treatment. The objective is to design an affordable and easily assembled body-powered, below-elbow prosthetic device for adults that provides basic arm function and can be widely distributed in developing countries. Therefore, cost, availability, functionality, and simplicity are the primary considerations of the design.

Measuring the Cell-Induced Deformation of Collagen Matrix Detected With Digital Holographic Microscopy

A modified Mach-Zender set-up in reflection is applied to record and reconstruct holographic amplitude and phase images. A charged couple device (CCD) is used to record a hologram and numerical reconstruction algorithms are then applied to rebuild the hologram for obtaining both phase and amplitude information. One could also focus on multiple focal planes from a single hologram, similar to the focusing control of a conventional microscope. The morphology and behavior of mammalian cells is determined by an interaction between signals from the intracellular matrix and the cellular responses. It is important to note that the physical aspect of the extracellular matrix is as significant as the chemical nature of it. Specifically the stresses, mechanical forces, and the profile of the external environment have major effects on cell behavior. The mechanical and physical characteristics of a tissue are greatly dependent on a hierarchical spatial arrangement of its extra-cellular matrix components. A key player in the ECM is collagen which exhibits significant tensile strength on the cellular scale. Digital holographic microscopy (DHM) is applied to study the deformation of collage matrix in response to cell migration.

Inverse Heat Transfer Analysis of Micro Heater Strength and Locations for Hyperthermia Treatment of Brain Tumors

Hyperthermia, also called thermal therapy or thermotherapy, is a type of cancer treatment in which the aim is to maintain the surrounding healthy tissue at physiologically normal temperatures and expose the cancerous region to high temperatures between 43°C–45°C. Several methods of hyperthermia are currently under study, including local, regional, and whole-body hyperthermia. In local hyperthermia, Interstitial techniques are used to treat tumors deep within the body, such as brain tumors. heat is applied to the tumor, usually by probes or needles which are inserted into the tumor. The heat source is then inserted into the probe. Invasive interstitial heating technique offer a number of advantages over external heating approaches for localizing heat into small tumors at depth. e. g interstitial technique allows the tumor to be heated to higher temperatures than external techniques. This is why an innovative internal hyperthermia research is being conducted in the design of an implantable microheater [1]. To proceed with this research we need complete and accurate data of the strength, number and location of the micro heaters, which is the objective of this paper. The location, strength, and number of implantable micro heaters for a given tumor size is calculated by solving an Inverse Heat Transfer Problem (IHTP). First we model the direct problem by calculating the transient temperature field via Pennies bioheat transfer equation. A nonlinear least-square method, modified by addition of a regularization term, Levenberg Marquardt method is used to determine the inverse problem [2].

SEM Validation Technique for FEA of Small Specimens

The use of the SEM to make direct surface measurements on small test specimens enables the FEA analyst to construct and validate an individual specimen model. The technique is also valuable to engineers so that they can calibrate their fatigue test samples before and after fatigue test regimes.

An Implantable Microbolus Pump With Contactless Rechargeable Battery Power Source Triggered by Remote Activation

We describe the design and testing of an implantable miniature infusion pump that uses a rechargeable battery as a power source. This design includes a receiver printed coil that allows inductive power transfer from a transmitter coil wound around a 20 cm diameter charging unit and a frequency-gated optical sensor that allows activation of the pump at a distance using pulses of infrared light. This mini pump can be charged in the home cage by inductive power transfer, and then operates independently from its power link in freely moving animals.

A Design Based Materials Study for a Wearable Muscle Stretching Device Aimed at Patients With Spasticity

The efficacy of robotic systems in rehabilitation is well established. Many of these systems are fixed equipment that requires the user to visit a facility for treatment. Furthermore, current treatment options for pediatric patients with spastic dyplagia include manual stretching of the muscle groups and serial casting in conjunction with Botox injections. The goal of this work is to develop a dynamic orthotic to stretch the muscles of the lower calf. A subsystem of this project is the development of wearable sensor system to detect spasticity and control the system actuators. A system of thin film sensors embedded into a novel composite structure is proposed. In order to develop a dynamic orthotic to stretch the muscles of the lower calf, a subsystem of this project is the development of wearable sensor system embedded into a novel composite structure [1, 2, 3].

A Pull-Out Resistant Pedicle Screw for the Osteoporotic Spine

Pedicle screws are commonly used in spine surgery to implant and affix metal devices to the spine. These screws are most commonly associated with cases that require rod or plate implantation. Use of pedicle screws in osteoporotic patients, however, is limited because they suffer from low bone mass density (BMD). The low BMD is harmful to patients in two ways — it leads to increased incidence of spinal trauma and also prevents surgeons from instrumenting osteoporotic patients because screws do not achieve the required fixation in osteoporotic patients [1]. The risk of trauma is increased due to the brittle bone and vertebral compression fractures, resulting in spinal misalignment and increased risk of future trauma. Instrumenting these cases with rods or plates, however, is impossible because osteoporotic bone is not strong enough to “hold” pedicle screws in, i.e., prevent screws from pulling out [2, 3].

A Steerable Mechanism for Wireless Capsule Endoscopy

Gastrointestinal (GI) disease affects millions of people worldwide and costs billions of dollars annually. Because the symptoms of GI diseases are often vague, physicians are often presented with gastrointestinal disease in advanced stages. Because conventional endoscopes often cannot reach all the way through the 20-foot small bowel, exploratory surgery previously was necessary to enable physicians to complete their diagnosis.

Modeling Energy Deposition in Very Thin Layered Media by Monte Carlo Simulation

A Monte Carlo model with special features for modeling of radiation transport through very thin layers has been presented. Over the decades traditional Monte Carlo model has been used to model highly scattering thin layers in skin and may inaccurately capture the effect of thin layers since their interfaces are not perfectly planar and thicknesses non-uniform. If the Monte Carlo model is implemented without special features then the results of the simulation would show no effect of the outer thin layer since the path length of most photons would be significantly larger than the layer thickness and the resulting predicted photon travel would simply not notice the presence of the layer. Examples of multi-layered media are considered where the effect of a very thin absorbing layers is systematically examined using both the traditional Monte Carlo and that with new features incorporated. The results have profound implications in the diagnostic and therapeutic applications of laser in biomedicine and surgery.

An Evaluation of the Stryker 90D Pedicle Screw for Use as a Revision Screw

The success of a spinal fusion is often judged by the amount of relative motion between vertebrae following surgery. Proper fusion is aided by fixation instrumentation as well as bone growth subsequent to surgery. In order to allow for proper fusion it is necessary for instrumentation to properly fix the vertebrae until sufficient bone growth has occurred. In many cases pedicle screws are used to provide posterior support. It is the purpose of posterior instrumentation to increase the rate of fusion [1]. However, due to deterioration in the holding capacity of the posterior instrumentation; the quality of the fixed joint can begin to degrade. If this deterioration is significant enough it requires removal or revision of the fixation instrumentation.