Great talk, Dr. Lee, and I'm going to shift gears a little bit and talk about quad autograft and why this is so awesome and hopefully many of you are using it or you'll start thinking about using it. These are my disclosures, none of which are directly relevant. As an overview, I'm going to start with a case presentation and then talk about just in general terms some of the factors that influence our choice of graft for ACL reconstruction and then give a little bit of historical perspective on quad autograft and highlight some of the literature in terms of biomechanical and clinical outcomes. So this is our case, a 29-year-old female who presented after injuring her left knee while playing soccer. You see a theme here for sure. She landed awkwardly and felt a pop, had immediate pain and swelling. She was unable to continue playing. On examined clinics, she had moderate knee swelling. She was able to straight leg raise. Knee range of motion was limited because of pain and swelling, and she did have some mild tenderness over the medial joint line. She had a positive Lachman. These were her x-rays and clinics, so nothing concerning there. And the initial plan of course was to obtain an MRI given the high concern for ACL tear. We started her in physical therapy to work on range of motion, decreased swelling, gait training, all of those important things. We know how patients go into surgery affects how they come out. And we started the discussion about ACL reconstruction in terms of graft choice. So Dr. Lee kind of laid the groundwork for that. So that's a very, very important discussion as we're all aware, talking about autograft versus allograft, the pros and cons, and then overall timing for surgery. These were some of the cuts from her MRI. So no issues with the meniscus, that central sagittal image. You see the ACL tear. And then of course on the far right, the typical bone bruise pattern. And then just a couple of the coronal images just demonstrating that bone bruising. So we'll get back to that case. Touching briefly on some of these factors for graft choice. So there are many factors that influence how we decide which graft to use. Certainly among the most important are surgeon experience, preference, comfort level. We see that described broadly in the literature. That has a huge impact. We also of course have to take into account patient age and activity level, their sport or occupation, and their desire to return to work or return to play. We of course evaluate their comorbidities and their BMI and take all of these things into account. We want to evaluate for high-grade pre-opnelaxity. Get any details of prior surgery and have a discussion about the patient preferences and expectations and then evaluate any rehab concerns. So we're taking all of these things into account when deciding which graft to use. You saw a similar chart in Dr. Lee's talk, but this is just to highlight that you see the native ACL up top and all the grafts that we use, they're all stronger than the native ACL. So we have a lot of good options, but I'll describe to you why quad is really one of the best. So quad tendon, what are some of the advantages? So it can be used with or without a bone block. It's an incredibly strong, robust graft. It's a large diameter. It can be used in primary or revision ACLs. It causes minimal donor site morbidity with regards to anterior knee pain and anterior knee numbness. We do have to acknowledge, though, some of the potential disadvantages. So there's an increased risk of proximal patella fracture if you actually harvest the bone block. There can be a lack of bone-to-bone healing if you're using an all-soft-tissue graft. There's a possibility of rectus femoris retraction or injury if the harvest goes up into the muscle belly. And then you can lose extension and quad weakness, extension strength and quad weakness, similar to what we see with the BTB. So some of these studies are dated, but I haven't really seen much more recently. So the study of the Academy in 2010 showed that 1% of orthopedic surgeons used quad tendon for ACL reconstruction. I think it's much higher than that now. There was a systematic review showing about 2.5% of all anatomic ACL reconstructions used quad autograft. And then a survey in 2014 surveying surgeons from around the country found that quad tendon was used in about 11% of all ACL reconstructions. And I do think we're seeing it used more and more commonly. So highlighting a little bit of this historical perspective, because I think it's important for us to understand where this came from. So quad autograft was actually first described in 1979 by Marshall et al. But at that point, it was a substitution graft, which involved extensive dissection and harvest of a 13-centimeter segment of the extensor mechanism, including the quad tendon, the prepatellar retinaculum, and the patellar tendon that is quite different from what we do in 2023. In 1984, Bluth reported his technique for harvesting the quad tendon with a patellar bone block. In the 90s, Fulkerson and others showed favorable results with the central third quad tendon with a patellar bone block. And then in 1998, Fulkerson actually described the first technique with the use of all soft tissue quad autograft. So this goes way back. And then in 1984, Stanisch et al. showed a 20% incidence of post-op pivot shift test with the quad tendon substitution graft. And then Noyes and others, again, with this substitution graft, showed that it was significantly weaker than the native ACL. It failed at a fairly high rate. And the substitution graft was, again, it's significantly different from what we use today. But at this point, because of these poor biomechanical results, the graft was actually largely abandoned. And then in the early 2000s, it was sort of a renewed interest. So there were studies describing the use of the central quad tendon with no bone block. It eliminated the risk of patella fracture. There was reduced OR time, easier post-op rehab, and less risk of anterior knee pain. And then other studies showing good to excellent outcomes using this free quad tendon graft. There was decreased donor site morbidity and, again, decreased or no anterior knee pain. So at this point now, people are saying, wow, the central quad tendon graft may be the least morbid of all currently used autografts for ACL reconstruction. So a little bit about the anatomy. This is important for us to understand. So the quad is classically described as trilaminar, consisting of superficial, middle, and deep layers. There's a thin, fatty layer that actually separates the rectus femoris and vastus intermedius. And for any of you who have harvested the quad autograft, you've seen this. Based on MRI, you can see the breakdown in terms of four, three, and two layers, definitely most commonly three layers. And in general, it's about 7 to 8 and 1⁄2 centimeters from length from the myotendinous junction to the superior pole of the patella. This allows for harvesting of only a soft tissue graft or soft tissue and bone block. The width ranges anywhere from about 2 and 1⁄2 to 3 centimeters. The greatest width is about 3 centimeters proximal to the patella. This picture on the right is a graft that I harvested recently. And you can actually see the layers, and you see that little strip of fat there, too. The thickness is greatest at its insertion onto the patella. It's relatively constant throughout the length. This is just a prepared quad autograft. So the thickness of the distal 6 centimeters of the quad is about 7 to 8 millimeters. The intraarticular volume, actually, which was highlighted in the previous talk, too, it's about 87 and 1⁄2 percent greater than that of a similar-width patellar tendon. And residual quad tendon is greater than that which is left after patellar tendon graft harvest. In terms of vascular anatomy, so there are three contributions, so medial, lateral, and peripatellar arcades. The medial arcade actually is comprised of anastomosis of the femoral artery, the descending geniculate artery, superior medial genicular artery. And it's located between the muscular portion of the vastus medialis and the medial portion of the rectus femoris and vastus intermedius. This blood supply actually is quite important. The lateral arcade is the long-descending branch of the lateral femoral circumflex artery at anastomosis with the superior lateral genicular artery and is located between the rectus femoris and vastus lateralis. The medial and lateral arcades actually anastomose within and between the rectus femoris. So key things to take away with regards to the vasculature is that a centrally-based graft within the quad tendon actually spares the lateral perforating vessels. It avoids violating the quad muscle and therefore decreases or mitigates the likelihood of developing a post-op hematoma. So that's a really important consideration. And then a little bit about the biomechanics. So when comparing quad to BTB, quad tendon has been found to be superior with regards to load-to-failure, strain-to-failure and Young's modulus of elasticity. There's a significantly larger cross-sectional area and significantly greater ultimate load-to-failure. So important to note though that most of this data is based on the quad tendon patellar bone block. So again, this is not all based just on completely soft tissue graft. Here they noted extension strength deficit after removal of the 10-millimeter-width central free tendon graft from both quad tendon and patellar tendon. The tensile strength of the quad tendon was reduced by about a third. And then post-harvest extension strength of the quad tendon was actually higher than that of the intact patellar tendon. And harvesting the central third of the quad tendon actually leaves a stronger extensor mechanism than after harvesting the patellar tendon. So all things to keep in mind. Some clinical results. So here graft failure rates were similar between quad tendon and BTB. There was no difference when testing A to P stability. At a year post-op there was no difference in the percentage of patients with a positive pivot shift test. But there was significantly less graft site pain in patients with quad autograft and lower rates of kneeling pain compared to BTB. So again, comparable survival rates and joint stability but fewer adverse donor site symptoms with quad tendon graft. Another study, this is a great study actually we frequently see at meetings comparing quad autograft with BTB and hamstring autograft. So here when looking specifically at quad versus BTB, there was no significant difference in several parameters. But quad tendon autograft showed less donor site pain. And then comparing quad to hamstring head-to-head, again, no difference in a lot of parameters as you see there. But quad autograft had improved mean Leishman scores. So they concluded that quad autograft has comparable clinical and functional outcomes and graft survival rate compared to BTB and hamstring autograft. And that quad autograft showed significantly less harvest site pain compared with BTB and better functional outcome scores compared with hamstring autograft. Here's an additional study too, just lots of support for the value of the quad autograft. They really concluded that ACL reconstruction using quad autograft provides satisfactory long-term clinical results and acceptable rates of complications and donor site morbidity. So then there's not a lot of data specifically looking at bone versus all soft tissue quad autograft. But this is a study from arthroscopy in 2021. They found that IKDC and Leishman scores were similar. More patients with bone quad tendon demonstrated rotatory laxity on pivot shift compared with patients with all soft tissue autograft. But there was no difference in re-rupture rate between the graft choices. But really, there's still a paucity of literature comparing these grafts. So I think we can do a better job and continue to investigate if there are really huge differences between the two. And then getting back a little bit to some of the important complications to keep in mind, so bleeding and hematoma formation. If the quad muscle is violated, this can happen, especially if you go lateral. Again, this gets back to the location of the vasculature, so really important to keep that in mind. You need to ensure adequate hemostasis during closure. Retraction of the rectus femoris muscle can occur, although this is rare. This can occur with the harvest of a full or partial thickness quad autograft. It can happen when the harvest actually spans the myotendinous junction. It doesn't seem to have functional consequences, though, but important to keep that in mind. And then patella fracture, this is very rare. It's really comparable to the rate of patella fracture with BTB. The bone block should not exceed about 30% of the patella thickness, and it should not be harvested from the lateral aspect of the patella. So getting back to our case, this was our soccer player. She came back two weeks later. She was able to ambulate normally, was not complaining of any gross instability. Her knee range of motion had improved with physical therapy. And at this point she elected to move forward with ACL reconstruction using an all soft tissue quad autograft. So these are some intraoperative pictures from this case. So I actually positioned the patient. She has her affected leg is in a leg holder. The contralateral leg is abducted. Actually I put it in the lithotomy boot. And then on the right you can see the harvest, and we used this sort of cigar cutter type device to release the graft. And there are several ways to do this, and Dr. Sloan is going to go through that in detail. This is preparing the graft on the back table and just measuring what's going to be our femoral tunnel volume. A few intraoperative pictures here. So normal medial meniscus, the stump of the ACL in that central picture, and then normal lateral meniscus on the far right. And then here you can see the femoral tunnel looking up. We see that nice donut or cortical button going up the tunnel and then flipping on that bottom left. And then on the bottom right is her quad autograft in place. I actually will then use a biocomposite interference screw in the tibial tunnel. So I put the knee in full extension and I put that screw in and actually, so I'll do that in the tibial tunnel and then back it up with an anchor. These are her post-op x-rays. She did great. So no problems there. So in summary, quad autograft is a great option for ACL reconstruction. It's a big, robust, reliable graft. It can be used in primary or revision cases. Several studies have demonstrated that quad autograft has less harvest site pain compared with BTB and better functional outcome scores compared with hamstring autograft. It's a fantastic graft. If you're not already using it, definitely consider it. Do it in the lab. You know, scrub cases with partners. Use it now. Use it often. It is a fantastic graft. So thank you so much for your attention.

quad autograft

ACL reconstruction

graft choice

anatomy and vascular supply

biomechanics and clinical outcomes