Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Aircraft technology helps diagnose artificial hip, knee problems

21.02.2003


To assess the wear and tear on jet engine parts, mechanics used an old technology called ferrography to run the aircraft’s lubricating fluid through a magnetic device to separate out metal shavings and other ferrous engine debris. A University of Rhode Island researcher uses a similar process to assess the wear and tear on artificial hip and knee joints so patients can reduce the number of follow-up surgeries they must undergo or reduce the time spent in revision surgery.



Donna Meyer, an assistant professor of mechanical engineering, anticipates using her research to create a "wear atlas" that can be used by orthopedic surgeons as a diagnostic tool. She said the atlas could be used to help identify the potential problems that patients are having with their implants prior to revision surgery.

Most artificial hips consist of a polyethylene socket and metal ball or metal-on-metal combinations that are connected to adjoining bones with screws or cement. Total knee replacements are made of similar materials. Over time as the ball, socket and bone rub against each other, tiny debris is produced and settles between the bone and the implant interface, discouraging the much needed growth of bone around the prosthesis. This contributes to the loosening and separation of the interface, which necessitates revision surgery to repair it.


"Polyethylene wear debris can be a significant problem for patients because a loosened joint can cause great discomfort," said Meyer, a Cranston resident. "If we can determine the number and size of wear debris contained in a patient’s synovial fluid, and also look at the ratio of polyethylene to other constituents like metal, bone, and cement particles, we can create a tool to assist in diagnosing the problem with the implant before surgery is necessary. Ultimately we would like to minimize the number of revision surgeries that patients face, or at least minimize the amount of time spent in surgery for additional operations."

Meyer takes a sample of a patient’s synovial fluid — " it’s a large component of the lubricating fluid around your knee or hip," she said — and uses a process called bio-ferrography to capture the tiny particles of polyethylene, metal, bone and cement using a very strong magnet. Since most of the wear debris isn’t magnetic and therefore wouldn’t be collected by the device, she adds to the fluid sample a magnetic compound that binds to the non-magnetic particles.

"We need to capture every tiny particle in each sample to make sure the atlas is accurate," said Meyer, whose research is funded by the National Science Foundation and the Rhode Island Biomedical Research Infrastructure Network.

Meyer’s interest in this research was sparked when she was a graduate student at Rensselaer Polytechnic Institute studying the lubrication of artificial hip joints. She talked to the chief of orthopedic surgery at the time at Albany Medical Center, who told her of his interest in bio-ferrography. She’s been researching the subject ever since.

Once she perfects the technique for collecting the wear debris, she will begin creating the atlas. Meyer said the atlas will be designed so doctors can easily compare a patient’s age, activity level, implant type and time since implantation with the size and composition of the wear debris to quickly determine which part of the implant is the likely cause of the problem. For example, small particles are more likely to lead to implant loosening. Large pieces of debris, on the other hand, contribute greatly to the wear volume, but it is not certain how much it contributes to implant loosening, if at all.

"The atlas can be used by doctors as a maintenance guide, in addition to a radiograph for example, and hopefully give more information about early wear detection, just like the guides used by aircraft mechanics," she said.

Todd McLeish | EurekAlert!
Further information:
http://www.uri.edu/

More articles from Process Engineering:

nachricht Etching Microstructures with Lasers
25.10.2016 | Fraunhofer-Institut für Lasertechnik ILT

nachricht Applying electron beams to 3-D objects
23.09.2016 | Fraunhofer-Institut für Organische Elektronik, Elektronenstrahl- und Plasmatechnik FEP

All articles from Process Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Simple processing technique could cut cost of organic PV and wearable electronics

06.12.2016 | Materials Sciences

3-D printed kidney phantoms aid nuclear medicine dosing calibration

06.12.2016 | Medical Engineering

Robot on demand: Mobile machining of aircraft components with high precision

06.12.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>