Tag Archives: hip replacements

What helps you may hurt you (titanium dioxide nanoparticles and orthopedic implants)

From a Sept. 16, 2017 news item on Nanotechnology Now,

Researchers from the Mayo Clinic have proposed that negative cellular responses to titanium-based nanoparticles released from metal implants interfere in bone formation and resorption at the site of repair, resulting in implant loosening and joint pain. [emphasis mine]Their review of recent scientific evidence and call for further research to characterize the biological, physical, and chemical interactions between titanium dioxide nanoparticles and bone-forming cells is published in BioResearch Open Access, a peer-reviewed open access journal from Mary Ann Liebert, Inc., publishers. The article is available free on theBioResearch Open Access website.

A Sept. 14, 2017 Mary Anne Liebert (Publishing) news release, which originated the news item,  mentions the authors,

Jie Yao, Eric Lewallen, PhD, David Lewallen, MD, Andre van Wijnen, PhD, and colleagues from the Mayo Clinic, Rochester, MN and Second Affiliated Hospital of Soochow University, China, coauthored the article entitled “Local Cellular Responses to Titanium Dioxide from Orthopedic Implants The authors examined the results of recently published studies of titanium-based implants, focusing on the direct and indirect effects of titanium dioxide nanoparticles on the viability and behavior of multiple bone-related cell types. They discuss the impact of particle size, aggregation, structure, and the specific extracellular and intracellular (if taken up by the cells) effects of titanium particle exposure.

“The adverse effects of metallic orthopedic particles generated from implants are of significant clinical interest given the large number of procedures carried out each year. This article reviews our current understanding of the clinical issues and highlights areas for future research,” says BioResearch Open Access Editor Jane Taylor, PhD, MRC Centre for Regenerative Medicine, University of Edinburgh, Scotland.

Before getting to the abstract, here’s a link to and a citation for the paper,

Local Cellular Responses to Titanium Dioxide from Orthopedic Implants by Yao, Jie J.; Lewallen, Eric A.; Trousdale, William H.; Xu, Wei; Thaler, Roman; Salib, Christopher G.; Reina, Nicolas; Abdel, Matthew P.; Lewallen, David G.; and van Wijnenm, Andre J.. BioResearch Open Access. July 2017, 6(1): 94-103. https://doi.org/10.1089/biores.2017.0017 Published July 1, 2017

This paper is open access.

Monitoring hip and knee replacements from inside

I have a fondness for the ‘My mother is a cyborg‘ posting that I wrote for April 20, 2012 largely due to the title which amuses and makes the piece easy to find. In common with this posting, ‘My mother …’ is about  replacements (hip, etc.) and nanotechnology.

Before spilling the latest news, here’s the reason for all the research interest in hip replacements, from my April 20, 2012 posting,

Since her [my mother’s] operation, I’ve become somewhat interested in hip replacements. From the April 19, 2012 news item by Anne Trafton on Nanowerk about research at MIT (Massachusetts Institute of Technology),

Every year, more than a million Americans receive an artificial hip or knee prosthesis. Such implants are designed to last many years, but in about 17 percent of patients who receive a total joint replacement, the implant eventually loosens and has to be replaced early, which can cause dangerous complications for elderly patients.

To help minimize these burdensome operations, a team of MIT chemical engineers has developed a new coating for implants that could help them better adhere to the patient’s bone, preventing premature failure.

There’s a researcher at Case Western Reserve University (Ohio) who is taking a different approach (from the MIT team) by utilizing an emergent process, magnetic particle imaging, according to the Feb. 5, 2013 news item on Nanowerk,

A Case Western Reserve University chemistry professor has begun imbedding magnetic nanoparticles in the toughest of plastics to understand why more than 40,000 Americans must replace their knee and hip replacements annually.

Anna C. Samia, an assistant professor who specializes in metallic nanostructures, has been awarded a five-year $600,000 National Science Foundation-CAREER grant to create new materials and equipment to test ultra-high molecular weight polyethylene used to make artificial joints. She and her team of researchers will also develop magnetic particle imaging techniques to monitor degradation and wear.

The US National Science Foundation gives more information about Samia’s project on her ‘Magnetic Imaging Guided Composite Materials Development’ Career Award webpage including this non-technical summary I’ve excerpted,

Polyethylene is widely used as a component in the fabrication of joint prostheses. A major downside of this material is that it can undergo excessive wear leading to premature loosening of the implant, which in turn can lead to failure and complicated replacement revision surgeries. Studies have shown that polyethylene wear in artificial joint replacements are not always identical and are not easily explained by exclusively mechanical factors. In cases of premature and excessive wear of polyethylene bearings, chemical degradation and oxidation of the polymer can significantly lower its mechanical resistance and result in an accelerated wear-off process. While ex vivo studies have been conducted on previously used polyethylene acetabular cups to understand the factors contributing to implant failure, the degradation mechanism is still not completely understood. An improved assessment of the structural integrity of the polyethylene material used in implants as subjected to mechanical and chemical stress will provide valuable information on the material’s durability, and can help predict its wear and degradation over time. To study the real-time degradation of implant materials in various chemical and biological fluid environments, the proposed project aims to develop new polyethylene composite materials that can be investigated using an emerging imaging modality called magnetic particle imaging (MPI). The proposed research will transform the wear debris monitoring of polyethylene implant materials and impact annually one million people in the U.S. alone who undergo hip and knee replacement surgeries. The educational impact of this project will build on current initiatives to educate high school, undergraduate and graduate students through the development of cross-disciplinary courses and hands-on research programs that will incorporate the interplay between materials fabrication and imaging tools. Moreover, a modular “Traveling Magnetism Show” will be developed for K-12 students at four adaptive levels and will be showcased in local schools and science museums. In addition, a new “Women in Chemistry Workshop Series at CWRU” will be established to provide a mentoring and training platform for graduate and post-graduate female chemistry students. [emphasis mine] This program will facilitate monthly discussions and workshops to tackle important aspects of career advancement specific to women scientists.

Future applications are also being considered according to the news item on Nanowerk,

Beyond artificial knees and hips, Samia said the nanoparticles, methods and technologies developed in this study would also be useful for learning how stents, electrodes, artificial organs and other implants degrade inside the body.

“A lot of other materials are used for implants,” she said. “It will be interesting to study them over time.”

As per my emphasis earlier, it’s intriguing to note that Samia’s grant is also being applied to outreach and support programs for female chemistry students.

The shrimp will save us

Who knew that ceramics are a preferred material for body armour? Clearly, not me. According to the June 13, 2012 news item on Nanowerk, there’s a shrimp whose shell may offer inspiration for better quality ceramics used not only in military body armour but also in joint replacements. Here’s an image of one type of mantis shrimp,

Flower Mantis Shrimp (Photo Credit Silke Baron)

Pretty, isn’t it? Here’ s more from the June 13, 2012 news item on Nanowerk,

A scientist from Nanyang Technological University (NTU) may be onto an ocean of discovery because of his research into a little sea creature called the mantis shrimp.

The research is likely to lead to making ceramics – today’s preferred material for medical implants and military body armour – many times stronger. These findings were published in last Friday’s Science (“The Stomatopod Dactyl Club: A Formidable Damage-Tolerant Biological Hammer” [behind a paywall]), and focused on the mantis shrimp’s ability to shatter aquarium glass and crab shells alike.

The common creature native to the Indo Pacific, has club-like ‘arms’ which can strike prey at speeds matching that of a 5.56mm rifle bullet. Each impact generates a force exceeding 50 kilograms, which is hundreds of times the mantis shrimp’s weight.

The June 13, 2012 news release from Nanyang Technological University (Singapore) notes,

Assistant Professor Ali Miserez, from NTU’s School of Materials Science Engineering (MSE) and School of Biological Sciences (SBS), collaborated with Dr James Weaver from Harvard University as well as scientists from the University of California-Riverside, Purdue University, and Brookhaven National Laboratory in the United States.

They have observed down to the nanoscale the highly unique composite structure of the mantis shrimp’s club and discovered that it is weaved together in a unique fashion to create a structure tougher than many engineered ceramics. This is the first time that the mantis shrimp’s club is studied in such detail.

“The highly damage resistant property of the mantis shrimp could be most useful in medical products such as hip and joint implants, as they sustain impacts hundreds of times daily during walking and daily activities,” said Asst Prof Miserez, a recipient of the National Research Foundation Fellowship, which provides a research grant of up to S$3 million over five years.

“Damaged hip implants are a real problem, and cost billions of dollars to the healthcare systems worldwide. They also cause painful surgeries to patients when they need to be replaced. Using a nature-inspired blueprint to design biocompatible implants is actually a ‘shrimple‘ solution.”

Thank you for that wordplay. ‘Shrimple’, indeed! More seriously, I have previously commented on hip replacements and the search for ways to improve them, most recently in my April 20, 2012 posting.

The June 13, 2012 news release from Nanyang Technological University goes on to discuss Dr. Miserez’s lab and other applications for the shrimp-inspired ceramic materials,

Designing a damage-resistant implant which is made out of a bio-compatible bone material would solve the above problems [bone loss, toxicity, and immune reactions], as the material exists naturally in the human body. Asst Prof Miserez, whose laboratory is situated at MSE’s Centre for Biomimetic Sensor Science, said they will continue their research to better understand the design and materials and will attempt to replicate it in the laboratory next year.

His team, which includes PhD student Shahrouz Amini, will be focusing on developing a new bio-compatible material which could be used for medical implants such as hip implants. However, the potential applications for these nature-inspired designs are widespread because the final product is expected to be lighter weight and more impact resistant than existing products. These could include new types of armour plating, lighter vehicles and tougher engine and aircraft components like pistons and gears, all of which suffer from impact, wear and abrasion damage over time. [emphasis mine]

Possible medical and military advances march hand in hand, again!