Kerby Joseph knee injury analysis - Part 2: Follow-up discussion
Digging deeper into what happened and what's next
This is a follow-up to my original Kerby Joseph knee analysis. You can start there if you wish:
Quick recap of Kerby Joseph speculated knee diagnosis
My speculation initially on X was that it was an articular cartilage issue that could be career-altering and even career-threatening…
A December 20 report from Dave Birkett of the Detroit Free Press appears to confirm that it is indeed a cartilage issue:
Now, here are some more questions and comments submitted on X/Twitter @JimmyLiaoMD. Appreciate all of you who follow and interact with me there. Consider this an open forum so feel free to leave your own insights and perspectives in the comments below or on X.
When did Joseph’s knee injury occur?
If this is articular cartilage damage, it can be either a gradual wear over time or a sudden breaking off of a piece - or both. Below is an image of a chipped off piece of the cartilage and bone.
In Brad Holmes’ postseason press conference, he said that Kerby’s knee issue was present during training camp. It’s possible something acute happened at that time, but I suspect it gradually started prior to that.
What are the possibilities of cartilage damage?
I agree that widespread cartilage damage is a very possible scenario. This might explain why a surgical repair was not attempted earlier.
What are some treatment options for knee articular cartilage damage?
With arthritis affecting almost all humans at some point, there are many treatments being tried to help with the pain. Low-dose radiation therapy is one of them, which might help with pain and inflammation.
However, radiation treatment would not help repair the underlying damage, so playing through would likely continue to worsen the symptoms and risk long-term knee health.
You are likely referring to ChondroFiller which is one of many different repair or “patching” procedures that attempt to fill in a defect in the articular cartilage. MACI (Matrix-induced Autologous Chondrocyte Implantation) is another well-known example. The patch repair is not going to be as good as your original cartilage though.
While repair could help with symptoms, it doesn’t change the underlying issues that caused the cartilage to wear out in the first place - whether it’s meniscus loss, anatomy, or playing a rigorous sport like football.
The idea of injecting stem cells to help the body regrow cartilage is exciting, but the reality is much more subdued. There may be some improvement in pain compared to placebo.
Whether it actually regrows real cartilage is a different question. I’m dubious at this time. Actually getting the body to regrow its own cartilage is the Holy Grail and we aren’t there yet.
There are some major caveats with PRP (Platelet-Rich Plasma):
Completely unstandardized product as there are 40+ products on the market - all with different components.
Most studies have shown no difference in outcome compared to placebo.
Studies used to “prove” efficacy often do not include placebo.
It can still be worth trying PRP as the downsides appear to be minimal to none. Expectations should be tempered though.
Is knee surgery still an option for Joseph going forward?
Kerby’s statements have implied that there is no surgical “fix”. This could mean that any cartilage damage is so widespread that it can’t be effectively repaired. Or maybe there is minimal damage, but he’s still having debilitating symptoms with it. Either possibility would not be good.
There is another possibility which is more optimistic - that he simply did not want to have a surgical repair procedure at the time… but may reconsider now that the season is over.
Hesitancy with surgery is understandable as there are pros/cons and there is no guarantee that these cartilage surgical procedures are going to be effective. It’s not as straightforward as an ACL or Achilles repair.
We’ll see if we hear about a surgical procedure over the offseason.
What do we hope to see with Joseph in the offseason?
Yes, earlier would be better with caveats.
OTA’s have a very limited, segmented schedule. Last season, it was only 3 days in a row and then a break. If Kerby can make it through 3 days of practice without swelling/flareup, that would be a good start, as he couldn’t make it through more than one practice in a row at the end of last season.
Training camp and the season are a much more rigorous, regular schedule which would be more of a proving ground. I don’t expect him to have a normal practice schedule though. I fully expect the Lions to give him a high percentage of days off to limit the wear-and-tear on his knee in the hopes he can make it through the season.
Is retirement on the table for Joseph?
Articular cartilage damage is something that just needs to be managed over the rest of your life as there often is no “cure”. Even if Kerby undergoes a repair procedure, it’s still something that will need to be managed.
Many players do choose to retire because they don’t want to do further damage which can and will affect the rest of their lives.
Should Joseph’s injury affect the Lions draft considerations?
Safety health is a major concern going into next season with Joseph, Brian Branch (Achilles), Thomas Harper (concussions), and Dan Jackson (leg). Branch may not be ready until mid-season. If Harper gets another concussion early next season, it could be career-threatening. Jackson’s leg is a mystery.
The Lions would be wise to plan accordingly, which may mean using a high draft pick on a safety. A 1st-round pick on a safety is not out of the question.
















It sounds dubious, at best, to expect Joseph to return to anywhere near his All-Pro form. It's sad.