Navigation Links
Rice University student engineers automate limb lengthening for kids
Date:4/23/2012

Another day, another four turns of the screw. That's just a part of life for people, primarily children, undergoing the long and difficult process of distraction osteogenesis, a method to correct bone deformities that leave one limb shorter than the other.

A team of Rice University undergraduates has invented a device they hope will make the process safer and easier.

In collaboration with Shriners Hospital for Children in Houston, the students came up with "LinDi," a self-adjusting, automated linear distractor. It eliminates manual manipulation of the screw with a motorized process that makes the gradual growth of new bone a more natural process. And for the first time in such a device, they have built in a force-feedback loop that protects fragile tissues and nerves from being overstressed.

To correct deformities suffered by as many as 10 million children due to trauma, infection or congenital causes, surgeons break a bone and apply a distractor that stretches the bone as it heals and gently nudges the arm or leg to a more appropriate length.

The distractor incorporates long pins sunk right into the bone on either side of the surgical break. As the bone heals, but before it sets, the patient uses an Allen wrench to give the drive screw a quarter turn four times a day and push the pins further apart a tiny bit at a time.

That's inconvenient, even risky if a child or parent forgets to make the adjustment, said Rice mechanical engineering student Raquel Kahn. And wearing the bulky brace is no treat, either.

Team members Kahn, Alvin Chou, Mario Gonzalez, Stephanie Herkes and Elaine Wong took LinDi on as their senior design capstone project at the behest of Gloria Gogola, an orthopedic hand and upper-extremity surgeon at Shriners who specializes in pediatrics.

"The process of limb lengthening -- essentially creating a localized mini-growth spurt -- works well for bones, but is very hard on the soft tissues such as nerves and blood vessels," Gogola said. "This team has done an outstanding job of designing a creative solution. Their device not only protects the soft tissues, it will ultimately speed up the entire process."

"The problem with the current device is that there's a lot of room for error," Kahn said. "You can imagine that one might forget to turn it once, or turn it the wrong way, or turn it too much. And a lot of problems can arise in the soft tissue and the nerves surrounding the bone. That's the limiting factor of this process. But LinDi implements a motor to make the distraction process nearly continuous."

Kahn said the motorized, battery-operated LinDi adjusts the device almost 1,000 times every day, "so the process is more gradual and continuous, similar to actual bone growth."

Working at Rice's Oshman Engineering Design Kitchen (OEDK), the students had access to all the materials and expertise they needed to conceptualize, build and test a prototype even while completing their coursework. "We're teaching students the importance of prototyping as early as possible," said Marcia O'Malley, an associate professor of mechanical engineering and materials science and the team's faculty adviser. "Even if it's cardboard and tape, they're able to visualize a project early in the process.

"One of the big features of this project is the force sensor," she said. "If the loads on the tissue are too high, the device shuts the motor off." O'Malley said early tests with strain gauges paid off in the team's level of confidence when the time came to build a working prototype. "The great thing about the OEDK is that everything is so accessible here. I could say, 'Well, that team over there is working with strain gauges. Go talk to them and find out how they're doing it," she said.

Current patients wear distractors for as long as it takes to complete the process, typically stretching a limb for two to four months, Kahn said. Then they leave the device on for six more weeks, like a cast, while the bone sets. Each of the Rice students wore a standard distractor (minus the bone-drilling part) for 24 hours to get a feel for what patients endure. "The hardest part was we kept banging into things," Gonzalez said.

But through interviews with Gogola's patients, they learned how tough children are. "We were really concerned, because it looks like a pretty scary, uncomfortable process," Herkes said. "It looks like a torture device. We asked one little boy who had it on his humerus his No. 1 complaint and he said, 'My school uniform is red, and it doesn't match.'"

Through Shriners, the team got the opportunity to perform short-term animal testing that "helped us work out some of the kinks we weren't aware of in the device," Herkes said.

"We've gotten some nice results," Kahn added. "Our device is doing what we want it to do."

Though the students are about to graduate, they expect another team to continue development of the LinDi. One goal will be to make the device less bulky, and therefore curtail wear and tear on both the distractor and the patient.


'/>"/>

Contact: David Ruth
david@rice.edu
713-348-6327
Rice University
Source:Eurekalert

Related medicine news :

1. University of Virginia Health System Medical Laboratories Selects Sunquest's Specimen Collection Solution
2. Akron Institute of Herzing University Launches Its First Bachelors Degree Programs to Prepare Students for Even Greater Success in Business, Health Care and IT
3. Most pandemic plans in Ontario hospitals have not been tested: Queens University study
4. San Diego State University and BIOCOM Institute Receive $4.95 Million Grant: The BRIDGE Project, Linking Education to Employment in San Diegos Life Sciences Industry
5. Smithsonian Institution, Arizona State University announce education and research partnership
6. Untreated poor vision in elderly linked to dementia, University of Michigan study shows
7. Giarmarco, Mullins & Horton, P.C. President Joseph F. Page to Speak at University of Michigan
8. Arizona State Universitys Decision Theater offers balance to an off-kilter world
9. Forest City Announces Joint Venture with Health Care REIT for University Park Life Science Properties
10. Herzing University Online Launches Master and Bachelor of Science Degrees in Nursing
11. Nurtur Acquires ActivHealth and Wellness by Choice; Gains Exclusive Partnership with Duke University Center for Living
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/27/2016)... ... 27, 2016 , ... More than a third of American adults are considered ... surgery has received increased attention in recent years, as an article published ... weight loss, most people are familiar with the basic requirements of maintaining a healthy ...
(Date:5/27/2016)... ... ... With over 60 percent of acute stroke survivors being left unable to ... in the rehabilitation process has steadily increased. Ekso Bionics had been working to help ... stroke. , Ekso Bionics has now received clearance from the U.S. Food and Drug ...
(Date:5/27/2016)... ... May 27, 2016 , ... Aimed ... by inspiring human interest stories, courtesy of leaders in the nursing and health ... the industry, from leading advocates and associations—namely Jones & Bartlett Learning. , Jones ...
(Date:5/26/2016)... ... ... There are many ways to cook a hot dog, but new research commissioned ... dogs straight off the grill. Of the 90 percent of Americans who say they ... hot dog, far outpacing other cooking methods such as steaming (12 percent), microwaving (9 ...
(Date:5/26/2016)... , ... May 26, 2016 , ... Connor Sports, ... basketball as a partner for the Tamika Catchings Legacy Tour that will ... industry leader in hardwood basketball surfaces in all forms and levels of the game, ...
Breaking Medicine News(10 mins):
(Date:5/25/2016)... MedDay, a biotechnology company focused on the treatment ... "High doses of biotin in progressive multiple sclerosis: extension phase ... Ayman Tourbah , Principal Investigator of the Phase 3 ... Neurology (EAN) in Copenhagen, Denmark . The ... on Sunday, 29 May 2016 from 14:45 to 16:15 CEST ...
(Date:5/24/2016)... --   , ... Endpunkte und demonstriert Ebenbürtigkeit bei der Gesamtreinigung des ... guter , Reinigung des ... (Logo: http://photos.prnewswire.com/prnh/20130829/633895-a ) , ... der MORA-Studie der Phase III für NER1006 (1 ...
(Date:5/24/2016)... Celsion Corporation (NASDAQ: CLSN ... an update on its ongoing OVATION study, a ... the Company,s DNA-based immunotherapy, with the standard of ... advanced ovarian cancer who will undergo neoadjuvant chemotherapy ... IL-12 DNA plasmid vector formulated as a nanoparticle ...
Breaking Medicine Technology: