Cartilage-Growth Gel Holds Promise for Sports Injuries and Joint Repairs


Image courtesy of Robeter/WIKIMEDIA COMMONS

Season-ending injuries. Chronic joint pain. Debilitating osteoarthritis. Costly knee replacements.

What do these all have in common? Damaged cartilage.

Cartilage is the softer-than-bone fibrous material that’s found in your nose and around joints. It provides vital cushioning. But when damaged, cartilage doesn’t grow back. That all may change thanks to pioneering research at Northwestern University.

Ramille Shah and her team used a nanofiber gel that closely mimics the body’s natural collagen tissue. When combined with a common surgery, the bioactive material can help recruit stem cells and stimulate cartilage growth. She collaborated with her mentor Samuel Stupp, who developed the nanofibers in a research effort at Northwestern’s Institute for Bionanotechnology in Medicine, which he directs.

Successful in rabbits so far, the cartilage research could make long, painful recoveries and complicated surgeries a relic of the past.

Medill Reports interviewed Shah, a professor of materials science and engineering at Northwestern, to talk about her research and what it could mean for sports medicine and joint pain.

First of all, what is nanotechnology, and what kinds of fields does it impact?
Basically, nanotechnology works on very small scales, usually below 100 nanometers. The nanometer scale is one one-hundredth the size of a cell. (Learn more about the nanometer scale here.) Nanotechnology can affect every field you can think of, from transportation to food to textiles – even sunscreen.

Ramille ShahRamille Shah How did you become interested in nanotech and orthopedics?
When I finished my PhD, I had a good background in regenerative medicine and tissue engineering, and I had worked with collagen. Nanomaterials was something that was on my radar, but I wanted to learn more about it. I got introduced to biomaterials as a senior at Northwestern, under Dr. Samuel Stupp. It really hooked me because I love research, and the outcome can potentially help someone improve their quality of life, especially if they’re in pain. Orthopedics sort of fell in my lap. My husband is an orthopedic surgeon, and he’s the one who actually introduced me to it,

How do you treat someone with damaged cartilage now?
Usually the first thing surgeons will try is called a microfracture technique, where they poke holes through the underlying bone. That allows blood from the bone marrow to come in and create a clot. It’s similar to when you get a cut. That blood clot works because it has all these growth factors, or proteins, that help regenerate the tissue.

But that’s not a perfect solution.
Right, because it causes cartilage with Type I collagen to grow, and not all cartilage is the same. The cartilage in your nose and the cartilage in your knee, for example, are very different. Nose cartilage usually has Type I collagen, and the area around your joints is made up of Type II collagen. With microfracture, usually the tissue that forms is Type I, so it doesn’t match what’s naturally there. In some cases, microfracture does relieve pain but, in a lot of other cases, it doesn’t do much.

So how does your gel encourage cartilage growth?
The gel is made up of these nanofibers that spontaneously assemble under specific conditions. So when you inject it into the body, as a fluid, it comes together and forms these long nanofibers that connect into a gel network. And collagen is fibrous, so the gel mimics what cells would normally see in the body. We also tailor an amino acid (compounds of the elements nitrogen, hydrogen, carbon, and oxygen that are the building blocks of proteins) to these fibers that’s bioactive. They bind to growth factors, or proteins, that help turn stem cells into cartilage cells.

Why doesn’t cartilage naturally grow back?
Good question. During development, cartilage is vascularized, meaning it has blood vessels running through it. But as you get older, those blood vessels go away. So if you damage it, it doesn’t grow back because there’s no bleeding. The other reason is that cartilage is very dense. So cells on the outside can’t migrate in, and cartilage cells don’t divide well. That’s why our medicine works. We’re supplying a scaffold, we’re supplying factors and we’re supplying a cell source by the microfracture procedure.

What kinds of injuries or surgeries could this change if it pans out?
With orthopedics, or sports medicine, it could definitely help athletes who have cartilage injuries. For example, if an athlete tears his or her ACL[a knee ligament], very often it comes with some sort of cartilage damage. It could also help elderly people, just because of the chronic wear and tear on their joints. Our new procedure is minimally invasive, it’s simple, and surgeons are already used to doing microfractures. It could decrease healing time, and with athletes, it could potentially decrease rehab time, too.

What are the next steps after successfully implanting the gel in animals?
First we need to reproduce this in a larger animal before going into clinical trials with people. It’s going to be a long process, but this first study at least showed proof that it can work, and hopefully it’ll show it again. It’s very promising.



what about for dislocated

what about for dislocated shoulder i have dislocated my shoulder over 15 times twice since ive had surgery and now recently the left shoulder would this help my shoulder get back to normal

I am scheduled for a full

I am scheduled for a full knee replacement 04/15/14. Have an appointment to discuss postponing the surgery. I cancelled a previous appointment 01/21/14 but reoccuring pain induced me to re-schedule. I am walking just fine right now and am pain free. Not using meds or even lotions. I take a lot of natural supplements for my entire well being and am basically in very good health, Had an intensive blood work up recently and the comment @ the bottom of the report was-excellent. Have a minor hypo-thyroid condition but get a feeling of mental fatigue about 5-6 hours after rising. This is so not like me. Just sent for Athletic Greens, an all natural energy supplement to hopefully address the lack of energy I experience every day. Being 78 years of age is taken into consideration but am still very active as a self-employed residential/commercial electrician. All this is leading up to--how close are you to actual clinical studies? I would be very interested in volunteering. Have recent MIR & xrays of my right knee, showing bone on bone. By all logical reasoning, I should be almost unable to walk and in severe pain/swelling. Perhaps the good Lord is sparing me the inevitable pain, etc. until I have the right knee surgically corrected. If I failed to mention, both knees are bone on bone. Sincerely, a hopeful candidate, William Aubut.

Hi Brenda,

Hi Brenda, I imagine they are still running clinical trials, but I would contact for more information. Best of luck! Bethany Hubbard Editor-in-chief, HELIX

x-rays of my knees

x-rays of my knees apparently show bone on bone with no cartilage. But I don't want knee replacement surgery! Is there any way to generate cartilage growth or replace cartilage in the knees?

i have a rotator cuff year

i have a rotator cuff year that cannot be repaired and I bone on bone . I am a candidate for shoulder replacement but have heard horror stories . I would be interested in being a volunteer for your study . Yourfriendanne@gmail,com

My 13 year old son has OCD in

My 13 year old son has OCD in his left knee. Would this technique be helpful for OCD? UC Davis is looking at three types of treatment. Graft cadaver bone and cartridge, graft the cartridge from the damaged area grow externally and then reattach.

Hi Donna, Since this was 5

Hi Donna, Since this was 5 years ago, I don't believe they are doing trials at this time. The Shah Lab currently focuses on 3D-printing of unique materials and tissue engineering. More information at: - Bethany Hubbard, Editor-in-Chief, HELIX

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