Printing new joints with a 3D printer: advancing regenerative medicine for Canadians

2070

Imagine the day when doctors repair damaged, diseased or arthritic joints with new ones ― not made of titanium or plastic ― but with a patient’s very own tissue. Driven by new research, that day is swiftly approaching.

Scientists at Mount Sinai Hospital’s Centre for Regenerative Medicine and Musculoskeletal Research, including Dr. Rita Kandel, are pioneering an entirely new frontier in Canada: the use of three-dimensional printing to construct replacement parts that mimic the patient’s own joint.

This powerful technology creates objects by laying down many successive micro-layers of material. In biomedicine, 3D printing can help generate a part of the human body that is an accurate replicate of a patient’s own structure.

With a rapidly growing population of older adults in Canada, these innovations couldn’t be timelier.

Joint replacements ― such as artificial knees and hips ― are increasingly common and are often essential for people with failing joints. However, despite being built of advanced materials, current replacement parts aren’t as durable as the original joints, as they:

  • Are most commonly made of metal and plastic
  • May require cementing to bone
  • Can deteriorate and come loose
  • Usually need replacing after 10 to 20 years

For the past few years, Dr. Kandel, a scientist at Mount Sinai’s Lunenfeld-Tanenbaum Research Institute, together with fellow Lunenfeld-Tanenbaum researchers Drs. Marc Grynpas and Andras Nagy, have been studying the use of stem cells in joint replacement, working with bioengineers, orthopaedic surgeons, veterinary surgeons, bone biologists and stem cell biologists to create replacement joints from a patient’s own tissues.

Dr. Kandel has also been working closely with Drs. Robert Pilliar and Ehsan Toyserkani of the Universities of Toronto and Waterloo, respectively, to construct highly personalized joints with the help of a three-dimensional printing machine.

“This is a real meeting of minds,” explains Dr. Kandel, who is also Chief of Pathology and Laboratory Medicine at Mount Sinai Hospital. “Dr. Toyserkani uses 3D printing to literally construct the joint using biodegradable material. We then take that joint and use the patient’s stem cells to grow actual tissue (cartilage, etc.) on it. The original damaged joint will be replaced by a joint made entirely of the patient’s own tissues. It’s quite extraordinary.”

These ‘bio-replacements’ stand to overcome many of the current limitations of traditional replacements, and could be used to repair joint tissues damaged by disease or injury, and could also play an important role in intervertebral disc, or even bone replacements.

“The joint is a very complex structure of specific shapes and all components have to work together to create the painless movement we experience when we move our knees and elbows,” says Dr. Kandel.

“Now, with 3D printing, we can tailor precisely the implant to the missing structure in a patient’s body. This work is a shining example of personalized medicine, because the tissues that comprise these joints are those of the exact patient who will receive the replacement,” she adds.

The team hopes to be testing this innovation in humans in the next few years. “The implementation of these technologies is not far off from clinical care,” notes Dr. Kandel.

From printer to bench to bedside…it’s all in a few year’s work at Mount Sinai.