There are a few research projects looking to improve treatments.

Knee replacement: Pretty standard at this point, where a surgeon surgically removes the knee joint and replaces it with a mechanical joint made from metal and plastic.

Membrane-induced Autologous Chondrocyte Implantation (MACI): Harvest cartilage-producing cells and let them multiply in a lab, then surgically implant them at high concentrations in joints where there is a need.

Osteochondral Grafting: graft some bone and cartilage from another part of the body, or from a donor.

Osteoarticular Transfer System (OATS) Procedure: Move non-load-bearing cartilage to load-bearing parts of the same joint. Only works with smaller injured sites.

Platelet Rich Plasma/Stem Cell treatments: plasma and other blood products are extracted from blood, with high concentrations of platelets and growth factors, sometimes adult stem cells that can still differentiate into bone or cartilage, and then inserted into areas that can use regeneration. They can use physical scaffolds to help the cells attach to the right places, and the stuff in the plasma ends up helping it regenerate cartilage in the right places. This remains an area of very active research.

There are also some more exotic avenues of active research. One I read about recently was a Columbia University project, funded by ARPA-H, in creating knee replacements made from a patient’s own biological tissue, grown into a load bearing knee joint, to be inserted surgically the same way an artificial knee would be, only made out of cells grown from the patient themself.

It’s an active area of development, and I’m pretty excited about what they might be able to accomplish in our lifetimes.

Yes it can be repaired and replaced to varying extents. The core problem with cartilage is its blood supply makes grafts and localised repairs difficult - but not impossible and there are new techniques being developed constantly at the moment.

The other option is a total knee replacement or even a partial knee replacement. That is basically replacing the articular surfaces with synthetic surfaces in the whole knee or one compartment.

Silicone injections doesnt make sense for this joint - its generally not so much a lubrication issue (the knee has its own lubricanta) and more an issue of pain from the carrilage or bone grinding on bone. Silicone would not gove a lasting benefit - the surface needs repairing.

Knee replacements work well, especially in younger people. Pain relief is a given and aim for this, the real issue is how much function is wanted and achieved The difficult end is restoring function for athletes. If the expectation is pain free walking or climbing stairs that is very achievable. Running and sports is doable but more difficult and a big part of all of it is the post op physiotherapy, and compliance & motivaton by the person having the op to do the work needed.

The other issue of course is cost. Its expensive and even in “free” healthcare systems there is usually a mininum threshold of pain or dysfunction that needs to be met before theyll pay for it.

For some people there’s cortisone injections. They don’t fix anything but reduce pain and inflammation. I’m actually a use case where that was enough for that occurrence. I had a sharp pain in my knee and the cortisone got rid of the pain and inflammation and that specific issue didn’t come back.

Of course now my knees are totally wrecked and the only choice they gave me is replacing them

PSA: I wish they told me more about strength and balance when I was evaluated. I wasn’t able to go through with it at the time and had no reason to believe it was urgent since I could live with the pain . However now after years of of being unable to use my knees, I clearly have weakened muscles in my lower leg, clearly do not balance as well, and have a hard time getting up from the floor. Even worse I keep reading that those are exactly what they look for in aging and independence. So now I still need the joint replacements but somehow have to rebuild my lower leg strength

They do. Artificial joints, and collagen injection.

Had cortisone, collagen, platelet rich plasma and something else I forgot. All offered varying degrees of temporary relief (2 or so months) Knee replacement has given years of pain relief. No running or court sports (tennis, basketball with stop/start cutting) but returned to backpacking and skiing in 6 months, ice hockey and rock climbing after a full year. (No bouldering, can’t risk landing even with crash pads). Occasionally have to ice for stiffness but pain is gone.

So I can speak to this with a bit of direct but still indirect experience.

My partner got an osteochondral allograft. Twice. Same knee. They had a big chunk of cartilage missing from a youth sports accident. The procedure is basically that they take a cadaver knee, they slice off a big chunk of new brake pad for you, soak it in your platelets to prevent rejection. Then they come in and cut off the back of the knee, and slap in the new brakepad.

Having gone through (as a witness, nurse-maid, driver, adjunct pt) the procedure twice in 4 years: your mileage may vary.

The first time was a bit of a disaster. Major prep and PT before hand. Good doc to do the surgery. Trouble started in recovery. Pain was so extreme couldn’t keep food down. Ended up with massive weight and muscle loss on the affected leg. Thigh and quads went as thin as my bicep. Very long time to recover, maybe 9 months. Leg strength came back (but never fully) Developed a “clicking” in the knee. Dr insisted it would smooth down. Partner insisted on getting back to high intensity physical activity soon, was able to do a hundred mile backpacking trip together. I think they were really trying to believe it worked more than it actually had.

Fast forward only a few years and it was worse than it had been before the surgery. And had created arthritis in the join above the knee. And also now had back and hip pain.

So, round two. Another year of pre-PT. Knee got bad to the point they couldnt even bike any more. Same routine. We were very worried going into it. Surgery happened in a day. Previous brake was down to bone. No cartilidge at all. Recovery went 10x more smoothly. Some weight/ muscle loss on that leg. But not NEARLY as much as before. Back and hip issues persist, but as of a hike up in the Waianae range yesterday, no knee issue pain. But now the back and hip issues are bad enough, well. Heal your back now with Norman Popovsky.

hard to say if it was worth it. I think in five more years we might have injectable treatments

Now it can be regrown! In trials.

https://www.sciencedaily.com/releases/2026/01/260120000333.htm

Please replace my knees

Yes it can, but depends on the cartilage type. There are surgeries to graft or replace meniscus, but they give a mixed effect.

Is your cartilage in question is the lining in the joint, you’re fucked.

Edit: reading comments, you might actually not, and it’s interesting. Today I learned.

I’m just guessing, but party of it might be the body tends to reject foreign material.

maybe in the future when “stem cell” research becomes more useful. but currently there isnt a way to completely restore function like a normal knee. you can get knee replacement surgery in extreme cases.

Yeah, its a sports related thing. When I was 12/13 I was a distance runner in track. A large chunk of cartilage actually came out of my knee and had to be removed as it had calcified. Now, at 39 I have to deal with quite a lot of pain and being a custodian I’m on my feet all day. I may be able to get help through the VA, but there’s no way I could prove it’s service related and while my insurance is pretty good, I don’t know how well I could cover the copay.