Episode 96 | Pain with Kneeling in ACL Rehab

What is up guys? Today, we are coming off of Thanksgiving here in the States. It was nice to just take a second to relax and breathe and to disconnect a little bit. I hope that you guys who were celebrating also had time to do that. If you are not from the States and did not celebrate Thanksgiving, I hope that you just had a good weekend. And for any of the new listeners here, welcome! Today, we are diving into pain with kneeling in ACL rehab. This is a question I get so much. And it’s probably one of those things where if you’re listening to this episode, you’re probably dealing with it and you’re probably wondering, is this common for ACLers? And I’m here to tell you it’s very common for ACLers. And it’s a common question we get. And today, I want to try and tackle this as best as we can. And if you’re an ACLer listening to this, you know what I’m talking about. If you’re a post-op and you do that first time where you try to put the knee down and you’re putting pressure on it, that kneeling sensation and feeling, people have different reactions to it, different feelings.

Today, we’re going to talk about some of the factors related to that and the different experiences. And one of the things to consider in this will be how close to post-op you are. It’s going to be much more sensitive post-op which makes sense, right? You’ve had the incisions done, you’ve had the ACL reconstruction done, and things like some of the sensory superficial nerves were potentially impacted. A possible graft was taken, which we’ll dive into here in a second. The sensitivity typically improves as time goes on. But the question is, how much? Well, that really depends. And I know you guys hate that question, but it is very applicable to this one. But I’m going to hopefully shed some light on this so that way you can really get the best answer here for what we know. And the best answer really here is just going to really depend on your situation. 

Why does this typically happen? Why do we get pain with kneeling in your ACL rehab? I just mentioned how close to post-op you are. There’s going to be more sensitivity there, the closer to post-op. What was done in the procedure? Think about this for a second. What did they do? There were likely some nerves that were impacted in this; sensory nerves to be specific. And if you listened to the previous podcast episodes, episodes 93 and 94, where we talked about numbness and specifically that infrapatellar branch of the saphenous nerve. That is a nerve that gets impacted during ACL surgery.

And while we talked about numbness in those episodes, this goes hand in hand with also pain. Because sensory nerves provide information, provide the input, as I had mentioned. Motor nerves are the output; they create the function. Sensory nerves and that’s what the infrapatellar branch of the saphenous nerve is. It’s a sensory nerve that creates afferent feedback for us and provides senses for touch, pain, temperature, vibrations, and gives our brain info about the environment around us. So this includes kneeling and feeling the pressure of kneeling and how that feels on your body. It’s a byproduct of the surgery just naturally for the sensory nerve and that specific nerve to be impacted. Luckily, in the majority of cases, this nerve being affected doesn’t really impact your physical function, or your ability to extend your knee. Sure, you might have some discomfort in that pain, but it’s typically not going to limit you from being able to extend the knee in most cases since it’s not a motor nerve. But it is going to affect the sensation and the things that you feel. 

Another thing that I mentioned in this podcast is nerve regeneration is a very slow game. We use the analogy of a turtle sprinting, which is not very fast. And this is the thing that I want you to think about here is that if we’re impacted based on the sensation, if we’re impacted based on the nerve, and if that nerve had might been cut or maybe it was stretched or some sort of impact to that specific nerve or the surrounding nerves, then that’s going to impact the growth and the healing. Therefore, it impacts your sensory input if that nerve is not doing its job.

And so here, what I want to make sure we highlight is that physiology shows us, and based on the research that nerves grow super slow, one to four millimeters per day. And sensory nerves tend to be better than motor. And it could take months to years for that to really regrow, that’s if they find each other. And even then it might produce a different sensation from when the sensory input does come back. So instead of maybe a palm-sized area that’s impacted, maybe it’s a little bit more specific. And again, this is going to be different from ACLer or to ACLer. But this is all a part of the nerve. That’s an impact on this. 

Now, let’s talk about what the research says about this. There isn’t very specific research on the why and all of these different factors related to kneeling pain. They have studied different techniques and procedures, especially the differences in graft types. Riaz in 2015, looked at kneeling with patients and they saw that 71 patients were operated on. They followed up with these people for three and a half years. The average age of these patients was around 30. Twenty-two of these patients had anterior knee pain on kneeling. Then, there were 23 that had paresthesias with the anterior knee, that basically means numbness. And so when you’re looking at 65 patients, and they looked at their ability to kneel, they looked at basically how long they could. Thirty-six of them were able to kneel for unrestricted periods of time, nine of them for 5 to 15 minutes, 15 could kneel for 1 to five minutes, and five of them could only do less than one minute. And then there were six that were unable to kneel overall. This gives you a little bit of an idea of the range of what people can feel. And this is three and a half years after. This is just some information of like, okay, why is it that I’m feeling this? Why hasn’t it really improved even though I’m 6, 12 months, or even three and a half years out from this? 

And this leads me to my next point, which is the graft that is used. Usually, there’s allograft which is taken from a cadaver, and there’s autograft that’s taken from yourself. The three autographs, either: patella tendon, quad tendon, or hamstring tendon are taken from your own self. The patella tendon, historically with research and anecdotally working with tons of ACLers at this point, tends to have more kneeling and patellar pain. It’s just natural, because why? The graft is taken from that point where that contact is going to be made. And when you look at the research, Corey and Spindler did some research comparing kneeling and pressure. And 31% of individuals in these studies with a patellar graft experience pain with kneeling following ACL surgery. Whereas when they compared it to the hamstring graft, only 6% of those felt pain while kneeling. So this is just something that you want to be able to factor in of like, okay, the graft type does matter. The research does show that. 

Now, let’s talk about some of the specifics here. Just think about like what’s being taken, especially with the patellar tendon. One is that there is a scar in the incision that is done at the front of the knee. There’s an impact there. The incision is cutting through the skin, which is going to impact the sensory input to that area. And then when you think about the next layer, they’re going to take part of your patella tendon. Typically, the middle part of your patella tendon, and they’re going to cut. So that’s the impact from a sensory piece there. Part of the bone on the top, part of that patellar tendon, or actually at the very base of your patella at the bottom is going to be taken. They’re going to cut a small little piece of that bone. And then the same thing is going to be done at your tibial tuberosity which is where the other side of that patellar tendon is anchored. They’re going to cut both ends. Usually, there’s a bone at both ends of the patellar tendon. And that is going to be impacted as well. 

Now, we’re taken away from the bone, we’re taken away from the tendon, we’re taken away from the skin, we’re also taken away from the sensory nerve that was potentially impacted as well. These are all things that are just part of the procedure and it’s basically weighing the risk-reward of, I want a functional ACL that is stable, that can let me do my things. And taking a graft from a site that is really good. I’m actually a fan of the patellar tendon. It’s a great graft. But this is a little bit of the trade-off with a good graft. And getting it from this spot in the ACL surgery versus the sensory changes that happen. It’s just a byproduct of doing the surgery. And then there’s a process of how it all heal and how does your body interpret that?

This isn’t to deter you from this graft. And as I mentioned, I actually like the graft. But it does come with that territory, and I’m hoping that this surgical technique will improve in the years to come so people can improve on that anterior knee pain or that kneeling discomfort. If we were to line up a hundred different ACLers, different ages, different types of body types, and different histories, and if we were to line them all up, most of them would have some sort of funky numbness or kneeling discomfort. That’s a pretty common thing that we see across the board. This would be something that is more apparent with people who get patellar tendon grafts because that is going to be taken from that area where you kneel. And so that’s where you would potentially see more of that anterior knee discomfort or that numbness and the kneeling pain.

You guys know I’m always honest with you in this process. And that’s what’s so important to manage expectations. And this podcast is focused on being real with you versus giving you what you want to hear or sugarcoating things, and that’s where this is really important. Is that I’ll get this question a lot of like, hey, I have this kneeling pain or this discomfort. And we’ll talk with athletes or even people through Instagram or email or whatever it is that they’re reaching out to. And we talk through this whole point of how it is a difficult question to answer. And I wish we had the answer, but we don’t. And these are the factors that are playing into it. The other piece to this is also how your rehab goes, how you rebuild the tendon site, how you do all these different things which we’re actually about to talk about here next. The things that will help in this process. And the things that you can do to best optimize for getting this kneeling pain to improve.

The first thing is going to be desensitizing. You want to make sure that the scar tissue around the actual incision is moving well, it’s gliding well, it’s moving like your other skin. And it’s not tacked down and it’s like really rough. You want to make sure you work on that early in the process once your wounds are healed, and you could start massaging into those areas with different techniques. You want to make sure that stuff moves well. The same thing with the patella tendon, especially if you get that graft. Make sure that your patella is mobilized and moving well. This can all help with making sure your body starts to recognize these things as normal. And then, even different textures like pressure or light scratching, things like that where you get input, can help to build afferent feedback to the brain and allow your body to start to interpret those, as hopefully not sensitive type positions or pressures. 

The other thing here is maybe you do have that sensitivity or that kneeling pain. What can you do to still get to those positions? Let’s say you do yoga or you’re trying to do a half-kneeling type exercise, or whatever that might be, maybe playing with your kids on the ground. Softer surfaces are going to be key. Being able to have a yoga mat or a pad, a pillow, or things of that nature. Hopefully, will help with the pressure compared to the ground, especially something like a hard ground or hardwood floor. So having something soft underneath your knee where the kneeling pain is, can help to maybe desensitize or just create a little bit of softness there, so it’s less firm pressure.

Time is a big one. So time further away from the surgery, the more healing potential your body has, especially if it’s also nerve growth related. The more time you got, the more healing capabilities you have. As I mentioned earlier, it’s also a part of this process. And if anyone can put a specific timetable on it, I’d question their understanding of this process. Because many of you listening might say, you don’t feel it at all. Maybe you felt it up until the six-week mark or the three-month mark and it went away. Maybe you’re at 6 or 9 or 12 months and it’s gone now. Or maybe your year’s out, and it’s still there. All with varying levels of how it feels and the feeling of it in general. So just know that you’re not crazy, it’s completely normal. When in doubt, always ask your healthcare professional, your physical therapist, or your surgeon, especially if this is something that is a limiter. 

And this is what leads me to my last point in question here. The question I’ll always ask my athletes: Is this kneeling pain limiting you from our work together? That’s one. And then making sure that, is it getting in your way of getting to your goals, that’s two. These are the two questions that I want you to be able to ask yourself. And this is what I ask them and if it’s not limiting them, and it’s allowing us to move towards their goals, then we’re good. If it is limiting them and it is limiting us from getting towards their goals, then we need to talk through strategies of how we can best navigate this, especially if it is a very big limiter. But just know that this is something that we can only do so much with the body, giving it time to heal, giving it the right environment, giving it the right textures and surfaces. And these are going to be what’s going to be key in order to work through this and make sure that you understand where this is coming from, and why you might be dealing with it further down the road than you think.

If you’re going through this now with this information, I encourage you to ask yourself the same questions: Is this kneeling pain limiting you from your work and your rehab? And is it getting in the way of you getting to your goals? Those are going to be the questions that you need to ask because it’s going to be a part of the process. It’s just working through and seeing, okay, can we still move the needle forward and can we also work to improve this? And then just seeing how does this play out over time? 

Again, when in doubt, ask the person who’s guiding you. But just know if you’re sitting here, I’ve got kneeling pain, you might be six months out, you might be five years out, it’s more normal than you think. I’m here to let you know I’ve got some kneeling numbness on my right side. I do not have any pain when I kneel. And that’s I would attribute mostly to not having a patellar graft. That’s the main thing. Work through all these problems that I had early on. Mobilize the tissue around it. Or maybe I just got lucky with my two ACLs. But plenty of ACLers I know are doing everything they can and they’re a year out, they are maybe six months out and they’re still dealing with it. So just know that you’re not alone. 

All right, team, that’s going to be it for today. Thank you so much for listening. This is your host, Ravi Patel, signing off.