Harris Slone:
Welcome to the Arthroscopy Journal Podcast. I'm Dr. Harris Slone from the Medical University of South Carolina.
Today I have the privilege of speaking with Dr. Gio Medina from Mass General Brigham and Harvard Medical School. We will be discussing how graft size may affect results between various autograft options.
Dr. Medina authored the paper titled No Clinically Significant Differences in Outcomes After Anterior Cruciate Ligament Reconstruction When Comparing Quadriceps, Bone-Patellar Tendon-Bone, and Hamstring Autografts of 9 mm or Greater. Her co-authors on this paper include Natalie Lowenstein, Jamie Collins, and Elizabeth Matzkin.
Dr. Medina, thank you very much for joining me.
Gio Medina:
Thank you for having me. It's a pleasure to be here.
Harris Slone:
So first of all, I really found this study fascinating. I thought it was a very well done study. There's been a lot of comparative studies, especially recently, looking between all three of these autograft options. But none, at least to my knowledge, have really looked at this when isolated or limited to larger grafts. So how did you get the idea to do this study?
Gio Medina:
So you're absolutely right, we have seen several studies comparing the grafts. Most of them comparing BTB to hamstring and more recently the quad tendon, right?
But the majority of them, they look into retear rates and not outcomes. So that's one of the reasons why we thought we could do this study to look specifically into the outcomes, because a patient might not retear their ACL, but they're not be doing fine, right? They have trouble with range of motion or they have pain or they're just not able to go back to play as they wished.
And particularly for our athletic population, that's a very important factor. And if they can't go back to play or at the level that they wish, that might be considered failure, right? But it depends on what you define as failure. And most of the studies they look, as I said, revision rates or retear rates. So that's one of the reasons.
In the last few years we've been looking more into a more holistic approach, if you say so, on the athlete, not only if they retear or not, but psychological factors and things that brought us this idea to look into outcomes.
And the second reason, I was at my fellowship when we did the study and I was working with Dr. Liz Matzkin, and we were always discussing there's this idea that the BTB was the gold standard for ACL graft, and some studies saying that the hamstring would have slightly higher rates of failure. But what we saw with her patients were that the hamstring were doing very well. Right?
And I asked her thoughts on it and she said, "No patient comes out of the OR with a graft less than nine." So then we thought about doing this study, checking the grafts and comparing and isolating the effect of size, because there are very few studies in the literature that would take into consideration the graft size.
Harris Slone:
So that's actually a perfect lead in to my next question, which was how did you determine the cutoff for this study to be nine millimeters? Was that something that you observed clinically? Was that because of Dr. Matzkin's practice of and philosophy of making sure that everyone had a nine millimeter graft or greater? And is that sort of what led to this? A lot of the previous studies looking specifically at hamstring grafts and retear rates obviously generally focused on that eight millimeter cutoff number. So how'd you get to nine?
Gio Medina:
So the previous literature that you're mentioning does focus on eight millimeters that that's what we've seen. A couple of the MOON study group that reported on results of hamstring tendon particularly, less than eight millimeters having higher failure rates, there is also systematic review that indicates a higher failure rates if the hamstring has less than eight millimeters.
And more recently, the Swedish and Norwegian registry data that compares hamstring to BTB, less than eight would have higher failure rates, but if more than nine would have similar failure rates.
But this actually was not planned. When we did a pre-analysis of our data, more than 90% of the BTB and the quad tendons had more than nine millimeters graft. So that didn't allow us to use eight millimeters or else we wouldn't have data for comparison.
Harris Slone:
Excellent. Can you discuss how you designed the study and specifically what outcomes you evaluated?
Gio Medina:
So this was a retrospective study based on the SOS database. So it's prospectively collected data, and we want to analyze the outcomes after ACL reconstruction using the different types of autografts, so BTB, quad and hamstring were included.
This was between 2010 and 2021. All patients who had an ACL were included, and we excluded those who had multi-leg revision surgery, didn't have all the patient-reported outcomes complete data, and clinical complications, and any associated injury that changed the rehab protocol. So let's say meniscal tear that had a repair or a cartilage procedure, because these things can change the outcome, so that we excluded so basically an isolated ACL tear.
Harris Slone:
And what were the sort of primary results or main findings of your study?
Gio Medina:
So the patient-reported outcomes that we analyzed were visual analog scale and KOOS pain. The Marx Activity Scale and the veterans ran for the mental and the physical component.
All of the patient-reported outcomes improved from baseline to one year post-op and two years post-op. And then we compared each graft, so BTB versus hamstring, BTB versus quad, and hamstring versus quad.
And we found that the BTB patients did slightly better at the one year after surgery and almost no difference at the two years mark. But neither these points were statistically significant, or clinically significant I should say. And we saw that based on the MCID, the minimal clinically importance difference, so there wasn't actually... And so we think that most of the difference found statistically was driven by a large data set, because we had 1,600 patients included in the study.
Harris Slone:
And so, one of the things that was interesting to me was, as you mentioned before, the vast majority of the patients who were included for initial screening had grafts that were large, over nine millimeters for quads and for BTBs, the vast majority of patients had very or what I would consider to be a larger graft. And then it was about 50% of the hamstrings were able to be included in that study. Is that correct?
Gio Medina:
Yes, that's right. And I think because of the BTB and quad, you can decide the size of your graft, right? So I think based on previous literature that showed that less than eight had a higher risk of failure, most surgeons were opting to get a bigger graft.
Harris Slone:
Yeah, and I would say that, and perhaps it's a little bit of reflection of the time period that this study, the data was collected over, but there's obviously a lot of ways now to make a hamstring graft a bigger graft as well. But it was still pretty surprising to me that a pretty large number of patients had smaller grafts with the hamstrings.
Gio Medina:
Yeah. That's a very good point that you mentioned, because that's what Liz always said in the OR, right? Nobody leaves with a graft less than nine.
And the way that she taught us how to do it is she used the all-inside technique, right? So you're using sockets on the femur and the tibia with a suspensory fixation, so you don't need a full-length tunnel. So that allows you to have shorter grafts. And then with that, you can fold it as much as you need and then you will get thicker grafts, so bigger. So I basically in the OR can control the size of my hamstring now with these techniques, you just fold less or more and you get bigger grafts.
Harris Slone:
Were there any findings in the study that surprised you?
Gio Medina:
No, I think because one of the reasons that we did the study was based on what we were seeing in clinic, it wasn't surprising that we found that the graft had similar outcomes if they were given a big enough graft.
Harris Slone:
What grafts do you most commonly use in your practice? And it doesn't sound like it, but has this study in any way changed your practice?
Gio Medina:
No, it didn't change. Although obviously that thought process of nobody leaving the OR with a graft less than nine, it's always in the back of my head.
But to answer your first question, I use all sorts of graft, BTB, hamstring, quad, allografts, and there are several factors that I use to decide which ones to pick for that particular patient, because obviously there's no graft that is a one-size-fits-all, right? I think each patient will have the graft that's better for that patient.
So patient age, if they have previous injuries or issues with their knee, I don't want to be doing a BTB on a person who suffered with chronic patellar tendonitis for instance.
The sport that they play plays a major role in my decision, right? I don't want to be doing a hamstring in a sprinter, for instance. Their age. I do a lot of skeletally immature as well, so I'm not doing BTB for them. And if they had a contralateral tear already and... So it's a multitude of factors that I consider before picking which graft to reconstruct their ACL.
Harris Slone:
Why do you think that a bigger graft results in a better patient-reported outcome? I can intuitively understand a little easier why it might affect their retear rates, but why their patient or subjective outcomes?
Gio Medina:
Well, I think they are kind of linked, right? If they are thicker, you would have more resistance to failure, and then they can have less failure rates, less retear rates, and then with that, less instability to their knee, so less pain, less effusion.
But having said that, I think there's possibly a limit to that, because initially I was trying to get a very robust bigger graft from almost all of my patients, but I started seeing some stiffness, some arthrofibrosis, especially with the quad tendon. And so I was thinking, "Yo, what am I doing wrong?" And then there was a recent paper that came out I think from Emory that reported exactly what I was saying, so females, quad tendons, and larger grafts having a higher risk of stiffness.
Harris Slone:
And meniscus repair.
Gio Medina:
And meniscus repair. You got it. You know that one. Yeah.
Harris Slone:
And so yeah, so I agree with you. I think that you can have a graft that is too big, for sure. And it sounds like you try and sort of customize graft size to the patient.
One of the things that I like about really with all of the graft options now is being able to customize the graft size. I think you can do it with BTB and with quad and now with hamstring pretty easily. And then I try and match the graft to the patient. If they have a little bit more stenotic notch, I think you've got to be really careful with a bigger graft and can get into trouble.
So I don't know about you, but I don't think that bigger is always a better graft. I think there probably is a limit at which point it can start hurting you more than helping you.
Gio Medina:
I agree 100%. And after I confirm my thoughts with that paper, I have changed how I harvest the graft and it's exactly what you explained. I try to customize based on the patient's size and their notch size and particularly with females. Right?
So for instance, the quad, I don't know if you do that as well, but when I harvest the quad, the width, I go a little bit less than what I want. Because the quad is so thick that after you prepare and you put your sutures in, it will end up being a nine and a 9 1/2. So that's usually what I use for my female patients. But for the bigger guys, then I can go 10, 10 1/2.
Harris Slone:
Yeah. The other thing that I think is something that I always think about, especially with my quad, is that I think one of the things I like about the quad is that there's not a lot of donor site morbidity. But in my just observation, I do think that the more quad that you take, maybe the sort of quad weakness might be a little bit more of a factor, especially if you're taking a bigger graft from a smaller person. Intuitively anyway it just makes sense that the morbidity of that graft harvest is going to be more notable for that patient.
So smaller patient, smaller quad, smaller graft, and that just sort of has been part of my practice and how I've tried to individualize my ACL reconstructions to meet the patients where they are.
Gio Medina:
Yeah, I agree. And I think also nature kind of tells you what the patient needs, right? So if you try to harvest, their tendon is not going to be huge enough that you can harvest a 10 or something. You'll have to see what you have as an option.
But I agree with you, if you can minimize the harvesting for that quad, you will probably have a better recovery, although I'm not aware of any study comparing strength or outcomes based on how much you harvested from the quad.
Harris Slone:
No, I'm not aware of that either. But I also do find that, and I had this conversation with one of my mentors recently, it's sort of a chicken or the egg thing to patients who develop sort of inter-knee arthrofibrosis lack that extension because they have difficulty recruiting their quad or do they have difficulty recruiting their quad because they have difficulty getting their knee all the way straight? And I've had some fun debates about that and it's probably some of both would be my guess, but...
Gio Medina:
Yeah, it could be both. But as I said, I've had patients that I had to take back because they had a lot of scar after the quad reconstruction, and you always see that bands of tissue connecting to the superior part of the notch. So that scar is legit. It's really there, right? But how much there's a contribution of the weakness of the quad, you're absolutely right.
Harris Slone:
So I'm going to ask you to sort of step outside of your current study and give me your expert opinion. So my understanding is that lateral extra-articular augmentation procedures, whether it's ALL reconstruction or lateral extra-articular tenodesis, the majority of the studies don't show improved patient-oriented outcomes. They tend to show better clinical outcomes in terms of stability and we think lower retear rates.
So do you think that if we have a small graft and hypothetically aren't someone who tends to fold the graft over to make a hamstring graft a bigger graft, or we harvest a small quad graft and it's not the size that we intended, should we be considering a lateral augmentation surgery for those patients?
Gio Medina:
I think so. Currently, my decision is most of the time based preoperatively with the risk factors that we know for retear, so hyperextension of the knee, hyperlaxity, cutting pivoting sports. But my final decision is during the examination under anesthesia. If they have a grade two or more pivot, I would lean into doing a LET or not.
But that's a very good question that you ask. If I'm not able to get a graft which is robust enough, I would definitely lean into adding an LET.
Harris Slone:
And that's your current lateral augmentation procedure of choice?
Gio Medina:
Yes, I do modify Lemaire.
Harris Slone:
Excellent. What are the limitations of your study and maybe what future research do we need to understand a little bit more on this topic?
Gio Medina:
We didn't analyze, for instance, LET because we didn't have that information available with this database. And we didn't include revision. We didn't see the retear rates between the grafts. I think these are the major limitations of this study.
Harris Slone:
Dr. Medina, thank you so much for sharing your thoughts with us today. I really enjoyed reading your article and I absolutely enjoyed discussing it with you.
Dr. Medina's article titled No Clinically Significant Difference in Outcomes After Anterior Cruciate Ligament Reconstruction When Comparing Quadriceps, Bone-Patellar Tendon-Bone, and Hamstring Autografts of 9 mm or Greater is currently in press and can be found online at www.arthroscopyjournal.org.
This concludes this edition of the Arthroscopy Journal Podcast. The views expressed in this podcast do not necessarily represent the views of the Arthroscopy Association or the Arthroscopy Journal. Thank you very much for listening. Please join us again next time.
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