In this video, Board Certified Orthopedic Surgeon Dr. J. Michael Bennett talks about three options for torn ACL reconstruction or repair. An ACL or anterior cruciate ligament tear is a common injury in contact sports like football and just last week it was announced that St. Louis Rams quarterback Sam Bradford would miss the rest of the 2014 season because of an ACL tear. It was Bradford’s second season-ending ACL tear in as many years.
The three options for torn ACL reconstruction that Dr. Bennett describes in the video are the hamstring autograft, the tibialis allograft, and the patellar tendon graft. He also talks about the types of patients normally best suited for each option — the option best for you may depend on your age and your activity level.
Here’s a summary of the video transcription.
Hello and welcome. My name is Dr J. Michael Bennett. I’m a Sports Fellowship Trained Orthopedic Surgeon at the Fondren Orthopedic Group. And today we’re going to talk a little bit about anterior cruciate ligament injuries, primarily focusing on the ACL tear as well as graft options.
Many times when you tear your ACL, your surgeon will often times discuss with you the different options you have regarding ACL reconstruction and you have, to break it down, basically three options to pick from. And today we’re going to go over those three options just so you have some idea of what to expect. In the end, it’s ultimately going to be your decision to discuss with your surgeon on which option you prefer, but this is a primer just so you understand the options in general.
First off, regarding the anterior cruciate ligament tear, this is the knee, okay, this is your femur, this is your tibia, you have two ligaments that crisscross each other and they’re called the cruciates because they are a cruciform configuration. The anterior cruciate ligament tear affects the ACL, which is this front ligament up here. You get a tear across the anterior cruciate ligament, which is from this lateral femur to the tibia here and it creates a rotational instability.
Most patients will feel this if they are cutting, or twisting, or pivoting. They feel a pop, they see swelling in their knee, and then they kind of feel the sliding sensation of their knee. It just doesn’t feel normal or it doesn’t feel like it’s almost attached. I’ve had patients describe it almost as, like, a detached feeling of their knee. If you do have an ACL tear, typically you make that call based on a physical exam as well as confirm it with a MRI. Next, the key is to make sure you don’t have any other injuries based on the MRI, like a cartilage injury, or a lesion, or a meniscus tear.
Once you and your surgeon have decided to proceed with ACL reconstruction, then you will decide on the graft options. The first graft we’re going to discuss about today, these are soft tissue grafts that we’re going to talk about right now, the differences are between autograft and allograft. At our practice, usually the autograft comes from the hamstring tendons. There are some doctors that use quadriceps tendon, autograft from down here. They also use patellar tendon autograft, which we’re also going to talk about here a little bit later.
But right now I want to talk about primarily soft tissue grafts, which means that you have soft tissue on either side of the graft, so when you place it through the tunnels of your knee, here, you have fixation of soft tissue to bone on either side. So the first graft we talk about is the hamstring graft and when everybody automatically hears, “Oh my gosh, they’re going to take my hamstrings.” They think that we’re going to go in there make a big incision in the back of the leg and take out this whole hamstring region and that’s not the case.
Often times what we do is we make a small incision at the proximal medial aspect of the knee right here, okay, and we dissect down and we find, this is called the pes anserinus. It’s called the pes anserinus because it’s like a fan like membrane, this tissue that almost resembles a ducks foot, pes anserinus means “duck’s foot.” And within that tissue are your hamstring tendons, primarily two of them, one of them’s called the gracilis, the other one is called the semitendinosus. Those are the two hamstrings that we’re interested in. The third hamstring is the semimembranosus, which is a little bit more posterior. It’s a larger tendon, but we do not harvest that and it’s in the back of the knee.
We go for these two primarily because they’re easily accessible through a small incision. What we do is we harvest and we take these distal third, approximately, basically right about here of the hamstring region, which is all tendinous and we take a little bit of muscular tissue too, but the majority of the hamstring muscle stays intact. You leave that alone and what happens over time is that this tendon, the muscle heals and you get a pseudotendon back into that region. Okay.
So once we take the hamstrings out, we loop them over as you see here, and we loop it over some sort of fixation device. Some doctors prefer screw fixation. Some doctors prefer a loop type fixation with a little button, which is the way that we do it here. And then we use screw fixation down here in the tibia, but we loop it through this configuration or this loop and then basically you make a drill hole through the tibia, the proximal medial tibia, and then a drill hole through the lateral femur, and then we pass the graft through the tibia, into the femur, where the graft sits in a socket here. Okay. It’s in a socket and then you’ve got that little looped area on the outside here, just like that, that locks itself on the cortex of the bone and holds that graft in position. On this side we usually like to use a screw type of implant right here to hold it fixated on the tibial side.
The other option for soft tissue graft is the allograft, and this is from a cadaver graft. This basically, the one we use is primarily anterior tibialis, although some doctors use posterior tibialis, but the same type of fixation can occur. Your doctor may want to have, may choose to augment these allografts with stem cells or PRP, but that’s up to your physician to decide that, but this is definitely another viable option. Based on the doctor you’re talking to or their practice will determine what type of graft they recommend for you.
Typically in my younger population patients, who are younger than age of 45 and between the ages of about 20 to 45, I usually recommend a hamstring autograft or an allograft, but I’ll lean more towards the autograft because it’s obviously better to have your cells and your biology already there and not having to worry about a cadaver graft growing into the surrounding scaffold of bone, but you still can have the other option of the allograft.
And usually allograft is recommended for anybody over the age of 40 that has an ACL tear that is active, but there are some newer techniques now regarding improving allograft integration with the surrounding biology and, like I mentioned before, that’s up to you and your surgeon, but it has to do with stem cells or PRP, some sort of augmentation of that cadaver graft. So that being said, this is just one graft option. This is the soft tissue graft option.
What we’ll talk about next is going to be the bone plug option, which is also an autograft or an allograft, and it’s the patellar tendon or the quad tendon graft and we’re going to go over that now.
Real quick, going back to the previous discussion regarding allografts, real quick, the standard process for preparing allografts decrease the incidents of risk of bacteria or viral transmission. And the standardized processes are so much better these days that the risks are probably around one in a million, in regards to the possibility if a transmission of bacteria or viruses with any kind of allograft, it maybe even smaller than that.
So in general, as far as transmission is concerned, the risks are very low. Now, you may want to confirm this with your physician, just to find out exactly how those allografts have been prepared. Some are irradiated. Some are actually washed or purified in a certain sense. So you may want to make sure that you discuss that if you have any interest in learning about that before your surgery.
The next graft option that we’re going to talk about right now is the patellar tendon graft. This is the gold standard graft and it is an autograft, however, you do have the option of an allograft, but this is the original graft for ACL reconstruction and what it involves is harvesting two bone plugs from the patellar tendon, which is your kneecap. And so you take a plug from the bottom of your kneecap and you take a plug from the tibia tubercle, which is this kind of nodular bony tuberosity right where the patella tendon inserts. And usually you harvest the the central third of the patellar tendon. You don’t take the whole kneecap, you only take a portion of it. And what it leaves you with is two blocks of bones. So there’s a block here, block here, and then in between you have this thick band of tendon and that thick band of tendon recreates the ligament, it recreates the ACL. And then when you fixate it, you can do the same thing that we talked about before regarding the previous soft tissue grafts, is you make a drill hole in your tibia, you make a drill hole in your femur and you pass the graft through both holes.
The difference is once again in the fixation. With a patellar tendon graft, you’re going to fixate it with a screw. So you’ll have a screw here on this side and then you’ll have a screw here on this side and the screws basically going to push this bone graft to the surrounding bone, so it incorporates. And there are different options regarding screws. Some doctors like to use metal screws. Some doctors like to use plastic screws. Some doctors like to use bioabsorbable screws, which means it’s like made of the same compound as bone. So that’s definitely an option for you if you choose to do the patellar tendon graft.
And this graft is definitely recommended for patients that are younger than age 25, but older than age 17 to 18 years of age, so their growth plates are closed. And it is also the recommended graft for any elite athlete that has a lot of like football players, anybody that that’s involved with contact sports because of the durability and the strength of this graft and the fact that it is an autograft so your cellular configuration and matrix there is intact and it has a better in growth rate to the surrounding bony matrix in the knee.
The other option that some doctors do as well is something called the quad tendon graft, which instead of taking the central third of the patellar tendon, they go above to the top of the kneecap and take a little plug of bone from the top of the kneecap and then the central, or not the central third, but a strip of quadriceps tendon superiorly and that leaves you with a bony plug on one side and a soft tissue limb on the other side. So with this type of fixation, what you would typically probably do is a screw fixation in the femur, once again for the bone, and then for the soft tissue portion of this graft, you could use a screw as well, or you could use, some doctors use staples, where they actually put a large metal staple over this graft portion, holding it next to the bone. I’ve seen other doctors tie it down over what’s called a post, which is where you actually take a little, it’s almost like a little screw with a washer on it and you tie the suture limbs that are from either end of the graft here around that to hold that into position.
Once again this is an autograft, so you have the benefits of having your own tissue and the better chance for incorporation of the graft. So anybody who is an elite athlete that does a lot of torquing, twisting, turning motions, I always recommend an autograft option. Anybody that’s a younger patient that does a lot of contact sports and activities, I always recommend a patellar tendon graft. And by the way, when we do harvest these plugs, we fill the defects up, the little plug holes up with allograft, which is a cadaver bone, so you do not have a big defect there a hole there where the graft is taken.
So in summary, we’ve gone through three different, primarily three different graft options here that you need to know about. First off, you have to decided where you fit in categorically. Are you within the ages of 18 to 25? Are you within 25 to 50? Are you 50 and above? Are you an active athlete? Do you play contact sports? What are your expectations regarding return to activities? I think for the most part in our practice, usually when we have patients that are 18 to age 25, we lean towards the patellar tendon autograft. Ages 25 to about 45, we lean towards the hamstring autograft option and usually 45 and older, we typically lean towards the allograft.
Now the allograft can, I’ve had patients within the 40ish range that would like to rather use allograft as opposed to autograft and that’s fine. One other option, a last option would be to use a hybrid where we actually take one of the hamstring tendons and then reinforce it with an allograft. And that’s another option particularly in patients that have very, very small, thin hamstrings because it’s important to have a certain diameter of graft to give you that strength and security for healing.
For us, we want at least about an 8.5 9 millimeter circumferential graft, particularly with the soft tissue grafts, and so, if we don’t get that with the hamstring harvesting, then we wanna augment that with a cadaver graft.
So I hope that helps and I have more information on my website at www.orthopedicsportsdoctor.com. If you have any questions or you’d like to come in for a consultation, please feel free. Give us a call at 281-633-8600. Thank you.