Hello, my name is Kaletsha Koraha. I'm giving this presentation on patella tendon ACL reconstruction. BTB is a gold standard. I'd like to thank arthroscopy Association of North America for giving me the opportunity to give this talk. I have no disclosures relevant to this talk. In this presentation, we're going to discuss the origins of ACL reconstruction, what is the optimal graft for ACL reconstruction, some pros and cons of the BTB graft, some modern day techniques, and outcomes. So we know the incidence of ACL reconstruction continues to increase throughout the years. This study by Spang and Associates found a 22% increase in the rate of ACL reconstruction from 2002 to 2014. And they found that this increase was primary in children and adolescents and could be due to sports specialization in youths and year round sports. They also found a higher incidence in males of concomitant meniscal injury compared to females. Where do we start with current ACL reconstruction with the patella tendon ligament? Well, before 1963, surgeons mainly performed repairs whenever there was an acute ACL tear. When there's a chronic injury, they did have reconstruction methods, but these had high failure rates. So in 1963, Jones thought of a new technique using the patella ligament. And what he did is he took a small proximal portion of the quadriceps tendon, a full length patella bone block and reflected the patella tendon off the tibial tubercle. He then drilled a femoral tunnel at the anatomic footprint and pass the graft into the femoral tunnel securing it on the femoral side with sutures. And this had a higher success rate in terms of re-rupture. However, there was a high complication rate. Obviously, the patella fracture was something that was high due to the full length patella block, and also stiffness if there was a graft mismatch. What is the current state of ACL reconstruction? Well, now we have many different ways we can do this surgery. In terms of graft choices, we have the BTB graft, we have the hamstring graft, we have the quadriceps tendon graft, various allografts and even synthetic options. We also have multiple ways to fix our grafts and to drill our tunnels. And with these various methods, we've noticed in the literature upwards of 90% success rate in terms of knee stability, patient satisfaction, and return to full activity. So what is the optimal ACL graft? Well, we know we want it to be biomechanically similar to native ACL. We want it to have stable initial fixation, which lends itself well to immediate postoperative weight bearing and rehabilitation. We want to have rapid biologic incorporation so that the tendon heals to the native tissues. And we want it to have a low morbidity rate. So this study by West and Harner looked at biomechanical properties of select ACL graft tissues. And what they notice is BTB, quadriceps and hamstring grafts all have higher ultimate tensile load and stiffness compared to the intact ACL. When looking at initial fixation stability, they noticed that traditional soft tissue fixation techniques such as the endo button had a higher ultimate failure load compared to metal interference grooves. When looking at biologic incorporation, and we learned from the Moon Group in 2011, when they looked at the cohort of 645 patients, that allografts had a four times higher rupture rate when compared to autografts. When looking at the same study by West and Harner, we found that healing in the BTB grafts was as quick as six weeks, where a soft tissue took up to upwards of eight to 12 weeks to heal. What about graft morbidity? We know that BTB grafts had a higher incidence of anterior knee pain, especially with kneeling. And also some long term studies demonstrated that BTB might have a higher detectable OA at long term outcomes. When looking at strength, we know that when taking the BTB graft, we might have weak quadriceps long term, when taking the hamstring graft that might affect our flexion strength. What are modern day techniques? Well, traditionally, when doing the BTB graft, we use a trans-tibial portal, but that led to a vertical femoral tunnel. And in the studies, we've noticed that vertical tunnel placement results in rotational knee laxity after ACL reconstruction. So modern day techniques have developed an intermedial portal where we can get that graft at that 10-30 or 130 position at the more native position of the ACL and that decreases the rotational knee laxity. This is a picture of the trans-portal technique, you can do this with hyper flexion, and you can get that natural position of the ACL and really eliminate that rotational laxity. What are some options for your independent tunnels? We can do the medial portal approach with a trans-portal guide. We now have options with low profile reamers that lets you do this in a traumatic manner. And you can also do the outside in approach using retro reconstruction guides. You can drill these full length or sockets for your femoral flexation. These are MRIs demonstrated trans-tibial approach on the left, you notice that vertical tunnel placement, whereas the native ACL on the right is more oblique position. And then our portal technique in the middle, you see that reconstructs the ACL at that native ACL position, which is more oblique and eliminates that rotational instability. For fixation, we have various techniques. Traditionally, we have some cross pin fixation, our traditional interference screw is on C. And even with the BTB grafts, we're able to do suspensory fixation seen on the left. And that allows us to have that high strength of that suspensory fixation can also do hybrid techniques as well. Many surgeons have started using internal brace, which allows us to augment our ACLs with high strength suture. And that's thought to increase the stability initially, and maybe allow for faster. What are outcomes? Well, Christian colleagues look at outcomes comparing hamstring tendon autografts versus patellar tendon autografts and a meta analysis of 47,000 patients. What they found is that BTB grafts had a lower incidence of failure compared to hamstring. And the odds ratio for graft failure was 0.83 favoring BTB grafts. Another large registry study in the Scandinavian literature looked at 46,000 patients and compared ACL reconstruction with BTB versus hamstring. And these authors also found a higher incidence of revision in hamstring tendons compared to BTB grafts. What about quadriceps tendon grafts? Well, this study by London colleagues evaluated 51 patients in a randomized control trial comparing quadriceps tendon and patellar tendon autografts for ACL reconstruction. Now they found no difference in laxity between the grafts. However, the quadriceps tendon graft had a higher incidence of pivot shift. When looking at morbidity of the grafts, they found the quadriceps tendon had less anterior knee pain, less harvest site pain, and less sensitivity loss. However, there's no difference in patient reported outcomes. Comparing BTB, quadriceps and hamstring grafts, the study by Belkin colleagues compared eight studies, mostly high level two studies, and found no difference in graft failure or PROs between the patients. However, they found two studies that found a greater laxity in the hamstring tendon group versus quadriceps tendon group. Why is the BTB the gold standard and what we use in all our high level athletes? Well, there's many different reasons. One has similar properties to the native ACL. You have that bone to bone healing, which allows initial fixation strength. There's more laxity in the hamstring group compared to the BTB group. When looking at KT1000 and Lachman, and higher incidence of pivot shift when looking at the quadriceps group versus the BTB group. Studies have also shown a higher rupture rate with hamstring tendon versus BTB grafts. We know with our BTB grafts, we get a reproducible graft size and less tonal widening. You can also preserve your flexion strength, which is important in females which already have a high quad to hamstring ratio. What are some of the disadvantages? There's a potential for graft mismatch, especially with taller patients. You have your donor site morbidity with anterior knee pain and sensitivity loss. There's a theoretical risk of patella fractures and late osteoarthritis and BTB grafts. Thank you everyone for your time and your attention.

ACL reconstruction

patellar tendon

graft options

fixation techniques

biomechanical properties