Episode 290 | The Fear Of Damaging Your New Graft After ACL Surgery

I’m going to start off this episode by saying your graft is super strong when it gets put in there. Don’t feel like you need to walk on eggshells, but also don’t be dumb. But you don’t need to feel fragile or scared that you’re going to mess it up. It’s locked in there after that surgery, and I feel like you guys need to hear this, and I’m going to elaborate more on this and really prove my point.

I dug into some research on this. It’s something that I have been wanting to share with you guys for some time. And then I got this message from a listener that just prompted me to be like, “All right, it’s time to do this,” because I think it’s really important because this is something that crosses every single ACLer’s mind, no matter who you are.

“I’m near the one-year post-op, and it’s been a long, hard road. I thought of something that I wish someone had said to me early on that may help someone else starting this journey. I was really scared of re-injury, and I wish my PT had reassured me that my graft was strong enough to handle the exercises and weight-bearing. I wasn’t given good direction on either of these, among many other inadequate things, and that has prolonged my recovery. If you feel your PT is directionless and confusing, I’d recommend seeking a different PT.”

I wholeheartedly agree. I really appreciate this listener sharing that because I feel like so many people will resonate with it. And honestly, I can’t believe I haven’t done an episode on this because I personally resonate with it so much after my two ACL surgeries.

If you’re a physical therapist or someone who supports an ACLer, this is real. And I also want to say that even if you’re told this, it doesn’t immediately mean that the fear just disappears. It’s not like someone tells you, “Okay, cool. I can do everything. No worries,” and suddenly you’re completely fine.

The fear is still there. An ACL injury is such a physical, emotional, and mental experience. Then you go into having a major reconstructive surgery, sometimes multiple surgeries, and for many people, this is their first real medical experience. I know it was mine. It’s daunting. Your world has been completely upended, things have changed dramatically, and now you have this new thing put into your knee. The last thing you want to do is mess it up. You feel fragile, and that’s fair.

I don’t want to completely disregard that feeling by saying, “Oh, it’s fine. It’s locked in there.” That doesn’t really address what is happening inside your head. Today, I want to really showcase why that feeling is so real immediately after surgery and why it can persist well into the weeks and months after ACL surgery.

The first two to four weeks, especially, that thought can sit in the back of your head. It’s a small little voice, even when you might feel like, “Okay, I’m fine.” Every time you take a step or move your leg, there may be a moment when you feel some pain, a zing, or some weird sensation in your knee, and then, depending on your personality and your experiences, you might freak out. You might spiral a little bit and think you damaged the graft because you felt that thing.

You may have been told the graft is fine, but I completely understand why that fear can still cross your mind. Most people are simply not prepared for this surgery or this process. They have a surgical consultation, and there’s not much preparation around what it’s actually going to feel like. It’s, “Here’s the medicine, here’s the surgery, here’s the graft, and here’s where you’re going to go to PT or go find a PT.”

A lot of times, people don’t even find their PT until after surgery. If you’re lucky enough to find a really good PT beforehand, they’ll prepare you for all of this. We do this for all of our athletes who are getting ready for surgery. But there are so many people who get blindsided by thinking, “Oh, I’ll just have surgery,” and then they come out of it thinking, “Oh, crap. This is hard. I feel pain. I’m worried. I’m worried about this knee.”

Most people aren’t prepared for that. There’s never really a conversation about, “Hey, that knee is strong. That graft is in there.” It’s usually just a step-by-step surgical process, without much expectation-setting or education around the specific things that are going to happen inside your head.

But those are the things that we as ACLers are thinking about. You’re scared that you’re going to have to go through this entire process all over again if you mess this thing up. I get it. And I want to say this flat out: the feeling that your graft is fragile, that you’re scared you’re going to mess it up or damage it, is super real.

I especially relate to it because I’ve had two ACL reconstructions. You want to protect a major and expensive surgery, and I’m not just talking financially. It’s financially expensive, but it’s also time-consuming, emotionally expensive, and physically expensive. There are a lot of expenses that happen through this process. It’s exhausting, and you hope to never relive it again.

There are so many people I get on calls with where they’re like, “I don’t really care to do X, Y, and Z. I just never want this to happen again to me.” Especially if you’ve had a really hard process or you’re not particularly goal-driven toward one specific activity, there are people whose biggest goal is simply, “Please don’t let this happen to me again.”

I want to share how I felt that fear too. Even after my second ACL reconstruction, I was scared of doing something wrong. You’d think after your first ACL, you’d have some experience and understand how it feels. If anything, I was more anxious with my second ACL. I was more protective of that knee, and I knew what the year in front of me looked like, so every little zing and every weird sensation in that knee got much louder in my head than it really deserved.

I also didn’t have as much support with my second one as I did with my first, so there were a lot of challenges there. But I’ve seen this fear play out in so many different situations with ACLers, especially during those first couple of weeks after surgery.

Imagine you’re post-op ACL, within the first two weeks. You might lift your leg awkwardly. You might step weirdly. Your dog might run into your propped-up leg. You might get tangled up with your crutches. You might lose your balance, slip, or catch yourself. It could happen in the shower, getting into or out of your car, out in public, or when the ground is wet or icy.

It could also just be you reacting to life. You drop a glass and instinctively react. You’re a parent and your little kid is about to fall off the couch or hit their head, so you react naturally to protect them. I relate to that, having a two-and-a-half-year-old, where you’re trying to save them from breaking their neck half the time.

The point is, you have to react to things. And if one of those things has happened to you and your stomach dropped, you don’t need to fault yourself for being dramatic. That’s exactly what this fear can do to people. It’s fair to have the space to feel that.

I’ll never forget one of my first ACLers remotely. I never worked with her in person, but I got to see her through the whole process, from prehab all the way to return to performance. During her first week after surgery, her dog ran straight into the side of her knee. She had a big, heavy dog, and she completely freaked out. And for fair reason.

We connected, she messaged me, and we talked through what happened. What did she feel in the moment? What was the mechanism? What did she feel immediately afterward? We talked through all of it. I was able to tell her, “I think you’re fine. I know that was scary, but I think you’re fine.”

Of course, we can’t predict with 100% certainty what happened inside the knee from a message. So we also talked about watching how her exercises progressed, how her knee responded, and what the coming days looked like. If anything concerning developed, she could alert me, and we could connect with her surgeon and decide whether it was worth getting checked further.

Within a few days, the issue had been resolved. There was nothing lingering. It was more the moment itself that panicked her, and then everything settled down. But that was the value of having someone who could talk her through it. Otherwise, she could have spent the next days or weeks navigating the process with anxiety, walking on eggshells, worrying about doing her exercises, potentially delaying her progress, and constantly worrying about her knee.

These things happen all the time to ACLers, and they may not even share them. They might think, “Oh, it’s a fluke. Whatever. It’s fine.” I think it’s important to work with a provider who allows you to share these things when they happen and talk through them so you can put that anxiety at bay. That’s what I think a good rehab provider and a good team in your corner do.

Now let’s talk about what would actually be a concern, because I’m not going to just dance around this and say, “Ah, it’s fine. Sunshine and rainbows.” Let’s talk about what could potentially be a red flag or a yellow flag.

A clear, audible pop is something to pay attention to. Everyone is familiar with that for the most part, but if you feel a very big shift and a pop, that’s something to note. A true shift in the knee where you feel the joint come out of place a little bit and then go back is also something to pay attention to.

I’ll never forget that feeling from my first ACL tear, when I felt the joint literally slide to the side and dislocate when it popped, then go right back. I’ll never forget that sensation. If you’ve experienced that, you know what that feels like.

A big spike in swelling is another thing to watch for. You’re going to be dealing with swelling after surgery anyway, so you have to account for what is normal for your particular post-op situation and anything else that could contribute to it. But a big, unexpected spike in swelling or pain is something worth noting.

If your range of motion regresses—your extension gets worse, your flexion gets worse, or you get stuck in a position after the incident and it doesn’t improve—that’s also worth getting looked at.

In general, think about a massive regression from where you were. If you have a very specific moment where you notice something happened and then things just don’t improve afterward, that’s when it’s worth talking with your team.

There is a true mechanism involved. That’s the thing you have to keep in mind. It generally takes something to actually put enough force on the graft to tear it. A sudden, hard force. An aggressive slip or fall with a significant shift in the knee where it really bends in and you dramatically fall. Not just a little slip where you lose your balance and catch yourself. That mechanism can look very familiar to the normal ACL injury mechanism in the first place. You may not be on a field playing sports or on skis, but it will typically feel more like that than a slight shift or awkward movement.

At the same time, let’s normalize something: it’s normal to feel zings, sharp pains, pops, crackles, and noises, especially close to surgery. Everyone is going to feel these things. I felt them all over the place, and I thought things were going wrong left and right.

But remember what just happened. You went through a major reconstructive surgery. That’s a second trauma on top of the original injury, and if those things happened close together, that layers into what you’re feeling and the pain and discomfort you’re experiencing.

The pain you’re feeling post-op should eventually shift. Early on, it can be sharp, intense, and even breathtaking. But over the course of the following weeks, you should generally see a transition toward more dull pain and aching, with less of that constant sharpness and fewer of those intense zings. That’s especially noticeable in the first three to five days and that first week. I’m not saying sharp pain can’t continue beyond that, because ACL rehab doesn’t always follow a perfect textbook, but eventually you should see a shift from that heightened post-op pain toward more dull achiness and less sharpness.

When something happens early post-op, remember that the knee is already irritated. You just added stress to a joint that has very little capacity right now. You slip, and the knee jerks a little bit, and your knee is basically saying, “I didn’t like that.” There’s a little zing, some sharpness, some pain.

That doesn’t automatically mean you damaged anything. Sometimes you simply push the joint beyond its current capacity, and it’s going to talk to you about it. In many cases, that settles down within a few days.

But when in doubt, contact your surgeon and your physical therapist. Give them a heads-up. They can help you work through it. We’ve done this with so many of our ACLers over the years, especially remotely, and in the vast majority of these situations, the graft is fine.

The biggest thing is to be smart about what you’re doing and set yourself up for success. If you have to navigate a crowd or use crutches in challenging conditions, plan for it. Don’t just react to it. Be smart. Shit happens. Sorry if kids are listening. But if we can plan around things, most of these scenarios are avoidable, outside of the things that are simply life. If it’s wet outside and you’re walking, things happen. If you’re in the shower and you slip because the bathroom is wet, that happens. You can’t control your dog 24/7. Those are the things we can’t always control.

But if you know there’s a situation where you could put yourself at unnecessary risk, control what you can. If you have a really slippery bath or shower and you’re going to attempt to stand up, think about that. Make it safer. Plan for it.

Now, here’s the main point of today’s episode: your graft is super strong when it gets put in there. Your knee is going to feel fragile because you just had major surgery. But what I don’t think is explained enough in this space is that the graft your surgeon put into your knee, the moment it went into the knee, was at least as strong as—and in many cases stronger than—the ACL that you tore.

If we’re talking about an ACL repair where they try to repair the native ACL, or the BEAR procedure, the newer procedures that aren’t traditional reconstructions, I’m not going to talk about those today because we don’t have the same tensile strength data available for the BEAR procedure. Those are repairs of the native ACL, and that’s a different story.

But for most of you listening who are having an ACL reconstruction and getting a new graft, this applies. The native ACL you tore can be technically weaker than the new graft you’re getting immediately after reconstruction.

Let’s connect this to numbers because I want you to understand what the data and biomechanics actually show.

Noyes and colleagues, back in 1984, tested the native human ACL and found that it failed around 1,700 to 2,200 newtons of force. That’s our benchmark. You can think of that as the approximate force range at which the native ACL fails.

Now let’s look at the graft that gets put into the knee. Remember, this is typically going to be an allograft or an autograft. An allograft comes from donor tissue, while an autograft comes from yourself. The common autograft options include the hamstring tendon, quadriceps tendon, and patellar tendon.

With the patellar tendon, the prepared graft construct used for ACL reconstruction has been tested in the range of roughly 1,700 to 1,800 up to around 2,900 newtons, depending on the study and graft characteristics. Research from Wilson 1999, Noyes 1984, and later reviews has demonstrated this range.

You’re looking at something that can be right around the native ACL or substantially above it. There’s going to be variability depending on how the graft is prepared, its dimensions, and the specific construct, but the important thing is that you’re starting from a very strong tissue.

The native patellar tendon itself is incredibly strong. Think about what that tendon has to do every time you jump, run, sprint, decelerate, and produce force through the knee. Taking a portion of that tissue and using it as an ACL graft gives you a very robust construct. You also have bone on both sides with a bone-patellar tendon-bone graft, which allows the bone portions to integrate into the bone tunnels.

The hamstring graft has a much wider range because there are different ways surgeons can harvest and prepare it. They may use the semitendinosus alone or include the gracilis, and the tendon can be folded into different configurations. Depending on the number of strands, the reported strength can range from roughly 2,400 newtons to as high as 4,000 newtons.

That’s where the idea of strands comes in. You have this long tendon, and you can literally fold and bundle it together. Think about taking a piece of string and folding it over itself multiple times. You’re creating a larger construct from the same tendon. That’s what I have for both of my ACLs, so fun fact.

For the quadriceps tendon, reported values are around 2,100 to 2,300 newtons in some of the research. And then you have allografts, which can have the widest range because donor tissue can come from different tendons and varies based on the donor and preparation. You can see values from around 1,200 newtons on the low end up to 4,600 newtons on the high end.

The point isn’t for you to memorize these numbers. The point is that there’s real variation across graft types and studies, but you’re generally starting with a very strong construct. These numbers also come from different experimental setups, graft dimensions, preparation techniques, and tissue sources, so you shouldn’t look at one number and declare one graft universally superior.

And that’s important because people love to argue about which graft is “the strongest.” You could look strictly at tensile strength and try to pick a winner, but tensile strength is only one part of the equation.

Cross-sectional area matters. Think about how thick the graft is. A larger cross-sectional area generally gives you more raw material to distribute the load across. A thin rope versus a thick rope is an easy way to visualize it. The thicker rope can generally handle more stress.

That’s one of the arguments people make when comparing grafts such as the quadriceps tendon. But even there, bigger isn’t automatically better. A graft that’s too thick can create its own issues, including problems with the femoral notch, so there’s always more nuance than simply saying, “Bigger is stronger.”

Then you have Young’s modulus. I remember learning this in PT school and talking about it in biomechanics and undergrad. It’s essentially the material’s resistance to deformation or stretching, independent of the tissue’s size.

The material itself matters. The quadriceps tendon, patellar tendon, and hamstring tendon aren’t made exactly the same way. Their material properties differ, and that influences how they respond to load.

Then you have stiffness, which is how much the actual prepared graft construct resists stretching. This combines the material properties with the dimensions of the graft. The patellar tendon is a great example because it has incredible stiffness. Think about how much force that tendon has to transfer through the front of the knee for jumping, running, sprinting, and deceleration.

So you have different properties working together. It’s not just tensile strength. You have cross-sectional area, material properties, stiffness, graft preparation, and other characteristics that influence how the graft performs and what it can tolerate.

And then there’s one of the most important things from a post-op perspective: fixation strength. When they do your surgery, the graft is placed through bone tunnels in the femur and tibia. That’s your thigh bone and your shin bone. The graft then has to be securely anchored in those tunnels.

Early on, the weak point isn’t necessarily the graft tissue itself. The fixation and the process of the graft settling into the bone are important considerations. That’s where you may have a button, a screw, or another fixation system holding the graft in place.

You may also hear about devices such as a suture tape or “internal brace” being used alongside the ACL reconstruction. That’s an area where we’re continuing to see research develop, and there is promising interest around how these constructs may contribute to stability and load sharing.

You don’t need to memorize any of this. The big takeaway is that several properties are working together to hold your knee stable immediately after surgery. It’s not just one number.

Whether you’re talking about an allograft, an autograft, a double, or a quadrupled hamstring construct, you’re starting from a strong graft. It would honestly be surprising to me if an early post-op movement caused you to simply tear straight through the middle of that graft.

The fixation point is something that has to be respected, but remember: the graft is secured with fixation. It’s not just sitting loose inside your knee. It’s anchored there.

The graft is strong, the fixation is strong, and your knee is not a fragile structure that is going to fall apart because you bent it a little bit.

And here’s one more thing that I think puts a lot of people at ease right away.

You come out of surgery, and your knee is usually straight. You wake up, and it’s straight. You might have a brace or immobilizer, maybe an ACE wrap, maybe ice, whatever your post-op setup is. Then you have to bend it. And bending it can logically feel like you’re doing something bad to the graft. Because the knee is straight, when you try to bend it immediately post-op, you’re hesitant. You think, “Oh no, I’m actually going to tear or stretch that graft.”

I remember feeling this with both of my surgeries. It’s this fixed, rested position, and then when you bend it, your brain tells you you’re doing something to that graft.

But here’s the important thing: as you move into knee flexion, you’re actually decreasing tension on the ACL.

The ACL is more taut toward terminal extension, particularly through the last portion of extension. As you move away from that position and bend the knee, assuming the foot isn’t fixed to the ground, you’re reducing the tension on the ACL. You’re giving it more slack. Going from straight to bending for range of motion does not add tension to the ACL. You’re actually decreasing tension on it.

What you’re feeling when you bend the knee immediately after surgery is the pressure of the fluid and swelling. You’re feeling pain, especially if you had a graft harvested. You’re feeling the incision. You’re feeling the Steri-Strips or glue stretching across the front of your knee.

It doesn’t feel great. But that doesn’t mean the ACL graft is being threatened by the act of bending the knee.

This is important because people can become so scared of moving that they actually avoid the very things that are necessary for recovery.

There’s a domino effect that I’ve seen so many times. Someone is afraid to do their exercises because they don’t want to damage the graft. They’re afraid to move the knee. They’re afraid to put weight on the leg. They’re afraid to load the leg. They’re afraid to progress to heavier loading.

And then they don’t regain their range of motion. They don’t regain normal everyday function. They don’t progress in strength. And that leads to delays in the process. Then comes that feeling of being behind.

If you’re hesitant in those first few weeks, you can end up kicking the can down the road. You don’t push things as much, and then you feel behind. If you have 20 visits, 30 visits, or even 60 visits covered by insurance, those visits can get consumed in the first three or four months without you actually reaching the point where you’re ready to push and progress.

Then your insurance runs out. You’re left trying to figure things out on your own. You’re doing the DIY process. And inevitably, sometimes people can end up with other problems because they weren’t educated about what they could safely do and were afraid to push. That’s why I say the fear itself can cost you more than the movement ever would.

This is something I feel particularly strongly about with seated knee extensions and open kinetic chain knee extension after ACL reconstruction.

It’s still demonized in this space. Surgeons still tell people they’re afraid it’s going to stretch the graft. PTs are still saying these things. We see it all the time. I had calls this week where people were telling me, “My PT says let’s not do this because it’s going to stretch your graft.” As much as we might think this is an outdated idea, it is still very present. And when you unnecessarily remove knee extensions from someone’s rehab, you’re leaving one of the biggest tools we have for rebuilding the quadriceps on the table.

Seated knee extension allows you to directly and progressively load the quadriceps. It targets the quad in isolation, and in my opinion, it’s one of the biggest needle movers we have in ACL rehab. If there were one exercise I had to pick to make sure we were doing properly, that would be very high on my list.

Now, you have to do it progressively. You have to be smart about it. You don’t go hot out of the gate and load something aggressively without considering where the person is in their rehab. But getting the quadriceps strong again is absolutely critical.

And that’s why who you’re working with is so freaking important. I feel like I’m a broken record at this point, but your rehab professional—the PT, the coach, the provider—you decide to work with is one of the most influential decisions you will make during this ACL rehab process. It’s not the surgeon. It’s not some random trainer. It’s the person who is guiding you through this long, hard process.

Obviously, biology matters. We can’t control every biological variable. But if biology is working with you, then having the right guidance, structure, programming, communication, and planning can be a complete game changer.

The right PT would have told you this before surgery. You would have had this consistently communicated to you. It would have been built into your programming. You would be able to ask questions when something felt weird, and you would have someone there to tell you, “Hey, this is normal. Here’s what we’re watching for. Here’s what we’re going to do.”

We talk about these things with every athlete we work with. Sometimes we have to have these conversations with people who are four months out, six months out, or even 12 months out and are still scared to move their knee because they’re afraid they’re going to tear their ACL.

And we’re saying, “This fear is actually costing you more than being able to push forward and get your knee into a better place.” That’s why I care about this so much. That listener who reached out was nearly 12 months into this process and felt like she could have been spared so much of that fear. Maybe it could have been addressed in the first week or two, or even the first month, simply by having a PT communicate, “Hey, this feeling is normal. Your graft is strong. I’m going to give you things that are within your threshold, and we’re not going to damage it.” That’s what a good provider does. Nobody reassured her. Nobody gave her direction. And it prolonged her recovery.

My goal with this episode is to put your guard down. I want you to know that you’re not going to damage or tear your graft because of some quick bend, step, or stepping off a curb. You don’t need to walk on eggshells. Now, don’t be stupid and think it’s invincible. There is a sensitive period, particularly around the three-to-nine-month mark, and especially three to six months, when the graft is going through ligamentization. That does not mean you go all out at three months and start cutting, pivoting, and doing everything you want to do. You still have to be smart about the process.

But most of you who are worried about damaging your graft are already so careful that you probably have very little to worry about from the things you’re imagining. The people who are thinking about this all the time are already being cautious. You’re not typically the person who’s going to go out at month four or five and randomly decide to cut, pivot, and do something reckless.

I really hope you’re able to listen to this, get value from it, see the numbers, and understand the biomechanics behind it. I wanted to share this from the perspective of someone who’s gone through it twice and has personally felt this fear. I’m going to finish this the way that I started it. Your graft is super strong when it gets put in there. Do not walk on eggshells in this process. It will do more harm than good. Don’t be dumb. You don’t need to feel fragile ever in this process, and I know it can feel that way, but you don’t need to feel that way. You’re resilient; you’re strong; you can do this thing. You don’t need to feel scared. You’re going to mess it up.

This is something that, as long as you’re being intentional and you’re working with somebody who knows what they’re talking about, you’re going to be fine. If you’re not working with someone who doesn’t know what they’re talking about, change it. Do something different. It’s something where you have to think about what the cost of that is. What is the cost of inaction? What is the cost of six months from now if you’re still in the same place, thinking about where you are because you just didn’t change anything? If you had one single thing to change, it’s to work with someone who knows this process.

Do not do it yourself. We have physical therapists on our roster. I tell people this not just because, oh, like we work with PTs; it’s because we don’t get trained in this in school. This is such a hard recovery, and it’s something that even PTs we mentor, and this is PTs who have gone through our mentorship who are still choosing to work with us, it is by choice because they don’t feel comfortable enough or they also just don’t want to handle it themselves.

So we are working with physical therapists who could guide themselves, but they’re choosing not to. And that’s one thing to put in perspective for you guys: they spent hundreds of thousands of dollars going through school, and they’re still choosing to find help even though they have been educated on this a bit more than most.

So that’s really important here, so make a good decision here on that because I promise it can make the difference in where you are in a week, in the way that you feel in a week, and especially where you’re at in three months, six months, and especially in what you care about most in your life. If you need help, if you need help, we’re here.

We’re here to help. We would love to help you. You can look at the show notes. If you are looking for help from anywhere in the world, we are here. If you need help finding someone local to you, we are also here to be a resource to point you in that direction. All that I care about is finding an ACL specialist to work with and just knowing that the graft is locked in there.

Go do the freaking thing. Until next time, y’all, this is your host, Ravi Patel, signing off.