04.15 21st Century Knitting Needles
21st Century Knitting Needles    

What do Grandma and Dr. Kaifeng Liu have in common? They both like to knit! Sort of…

The knitting needles you're probably familiar with are straight, metallic, and used to create lovely scarves, socks and sweaters out of yarn. There are also many similar types of needles for sewing, embroidery and crocheting, just to name a few. What does your favorite relative have in his/her needle collection?

Admittedly, Dr. Liu's needle collection is a bit different. That's because Dr. Liu is a pediatric surgeon who is currently doing research in microsurgery in Dr. Gary Visner's organ transplantation laboratory at Boston Children's Hospital. Rather than knitting colorful accessories, Dr. Liu uses his needles to sew skin back together. Nevertheless, surgical needles in the 21st century are still modeled after the common knitting needle. The C-shaped surgical knitting needles Dr. Liu uses require two hands to function: one to hold the needle and create the hole for the suture, the other to hold tweezers and pull the suture through. The process can be cumbersome, your hands can get tired, and there is more possibility for tissue damage and human error.

His idea was to make a magnetic needle that was as small as possible—just enough to guide the suture—so that the surgical process could be done with one hand.

With plenty of experience using surgical needles in the operating room, Dr. Liu thought he could create a better tool that could get the job done more precisely in less time with less possibility for error. His idea was to make a magnetic needle that was as small as possible—just enough to guide the suture—so that the surgical process could be done with one hand.

To begin, Dr. Liu took a trip to Toys “R” Us® and the local hardware store to buy a variety of readily-available needles and magnets. He brought his purchases to the laboratory where he began assembling prototypes for his miniature magnetic needle. There were many variables that had to be optimized: the materials for the needle, needle shape and size, and magnetic strength, just to name a few. After many attempts, Dr. Liu finally found what he believed was a good model, and began testing with animal tissues.

Dr. Liu's needle in use.

Based on his experience in animal tissue, Dr. Liu further revised his needle prototype to the point where he is now ready to begin trials in animals. "Animal surgeries are often even more difficult than human surgeries because the tissues are just so tiny," explains Dr. Liu. If his needle prototype is successful, Dr. Liu hopes to continue testing his prototype in human surgeries. He is also looking to work with a company that can manufacture the needles in large quantities. "Right now, I’m still making them under the microscope in my laboratory," Dr. Liu laughs.

Dr. Liu hopes that the story of this novel surgical needle will encourage other discoverers and inventors—young and old—to solve problems they come across in their daily lives.

Dr. Kaifeng Liu was trained as a pediatric surgeon in China and is now a research fellow at Boston Children’s Hospital in Dr. Gary Visner’s laboratory. His invention received an award at the Boston Children’s Hospital Global Pediatric Innovation Summit  and Awards. When not in the clinic or laboratory, Dr. Liu enjoys swimming, biking, and camping.

To Learn More:

  1. Liu, K. et al. 2014. "Inhibition of the Purinergic Pathway Prolongs Mouse Lung Allograft Survival." American Journal of Respiratory Cell and Molecular Biology, 51(2): 300-310.
  2. Feblowitz, Joshua. “Magnetic needle tackles suturing in challenging surgical fields.” Vector: Boston Children’s Hospital's science and technology innovation blog. 27 Oct 2014. http://vectorblog.org/2014/10/magnetic-needle-tackles-suturing-in-challenging-surgical-fields/
  3. "Extremely Short Magnetic Needle." Boston Children's Hospital Technology and Innovation Development Office. http://www.childrensinnovations.org/SearchDetails.aspx?id=2607

For More Information:

  1. Suturing Techniques. http://emedicine.medscape.com/article/1824895-overview
  2. How To Suture With Dr. Bones. https://www.youtube.com/watch?v=5GlkuxNdTgc


Written by Rebecca Kranz with Andrea Gwosdow, PhD at www.gwosdow.com


All content on this site is © Massachusetts Society for Medical Research or others. Please read our copyright statement — it is important.

Dr. Liu performing microsurgery

Want to see how traditional is done? Here’s a video clip from the Duke Medical School. Notice the curved needle.

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