Knee Ligament Injury: Anterior Cruciate Ligament Surgery with Dr. Will Duncan

Dive into the complexities of ACL ligament injuries with our latest podcast episode on Aussie Med Ed, featuring Orthopaedic  surgeon Dr. Will Duncan.  Join host Dr. Gavin Nimon as he unpacks the pivotal role of ligaments in knee functionality, the increasing prevalence of knee injuries among athletes and the general population, and the groundbreaking techniques in ACL surgery and recovery. Discover insights into the unique challenges faced by female athletes, the integration of cutting-edge surgical approaches, and the comprehensive rehabilitation strategies essential for optimal recovery. Whether you're a medical professional, a student, or simply fascinated by the intricacies of sports medicine, this episode offers valuable perspectives on managing and overcoming knee ligament injuries. 

Dr. Duncan brings to the table his extensive experience in treating elite athletes, offering a rare glimpse into the challenges and triumphs associated with ACL surgery. The conversation navigates through the nuances of different ligament injuries, exploring the advanced surgical techniques that have revolutionized patient outcomes. Moreover, the episode addresses the unique vulnerabilities female athletes face, attributed to anatomical and hormonal factors, and the innovative approaches tailored to mitigate these risks.

Listeners will gain an understanding of the comprehensive rehabilitation protocols critical for a successful recovery, highlighting the importance of early intervention, customized physical therapy, and the psychological resilience required to overcome such a significant physical setback. This episode not only serves as an invaluable resource for medical professionals and students keen on the latest developments in sports medicine but also offers hope and guidance to those affected by ACL injuries, underscoring the possibility of returning to full functionality and an active lifestyle.

Available now on YouTube – Subscribe and elevate your understanding of sports-related injuries and their impact on mobility and quality of life.

Aussie Med Ed is sponsored by OPC Health, an Australian supplier of prosthetics, orthotics, clinic equipment, compression garments, and more. Rehabilitation devices for doctors, physiotherapists, orthotists, podiatrists, and hand therapists. If you'd like to know what OPC Health offers.

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Transcript

Dr Gavin Nimon: 0:21

ACL ligament injuries, the anterior cruciate ligament. If you're an athlete, a fitness enthusiast, or anyone who's ever taken a misstep, a ligament injury to the knee can be disastrous. Today, we're diving deep into a topic that touches the lives of so many. These complex injuries can sideline the best of us, affecting mobility, stability and overall quality of life. From the anterior cruciate to the posterior cruciate, the medial collateral or the lateral collateral, each ligament plays a critical role in the function and support of the knee. Today we're joined by Australian Rules football surgeon, Dr. Will Duncan, as we discuss his thoughts about these complex injuries. Welcome to Aussie Med Ed. G'day and welcome to Aussie Med Ed, the Australian medical education podcast, designed with a pragmatic approach to medical conditions by interviewing specialists in the medical field. I'm Gavin Nimon, an orthopaedic surgeon based in Adelaide and I'm broadcasting from Kaurna Land. I'd like to remind you that this podcast is available on all podcast players and is also available as a video version on YouTube. I'd also like to remind you that if you enjoy this podcast, please subscribe or leave a review or give us a thumbs up as I really appreciate the support and it helps the channel grow. I'd like to start the podcast by acknowledging the traditional owners of the land on which this podcast is produced, the Kaurna people, and pay my respects to the Elders both past, present and emerging. I'd like to remind you that all the information presented today is just one opinion, and that there are numerous ways of treating all medical conditions. Therefore, you should always seek advice from your health professionals in the area in which you live. Also, if you have any concerns about the information raised today, please speak to your GP or seek assistance from the health organisations such as Lifeline in Australia. And today we're joined by Dr. Will Duncan, a specialist orthopaedic surgeon whose work focuses on the injuries of the knee. He's involved in the treatment of elite athletes and professional sports teams, and he also looks after the management of degenerative arthritis, for patients who want us to keep moving. He has a particular expertise in anterior cruciate ligament injuries, particularly complex ones, as well as arthroscopic meniscal repair, joint resurfacing, and cartilage restoration. Dr. Will Duncan has an advanced fellowship in joint replacements, which he obtained from Exeter in the United Kingdom, and works in a sports knee injury clinic, and consults at Wakefield Orthopaedic Clinic and Clare Medical Centre. He's going to talk to us about cruciate ligaments in particular, but also about ligament injuries around the knee. And we're looking forward to hearing his expertise in that area. Welcome Will Duncan. Thank you very much for coming on Aussie Med Ed and to talk to us about this really important injury. Obviously, knee injuries themselves are the bane of all sports people. Can you tell me, first of all, who suffers a knee injury? What sort of people suffer a knee injury? I presume there's sports people and also a generalised population get injuries too? Perhaps you can outline the sort of people you see.

Dr Will Duncan: 3:07

The people that I see are predominantly sports people, they're younger patients generally that's where the highest increase in injuries is occurring over the last decade. It's in our young athletes that are performing, a lot more single sports. They're not doing a variety of sports that they used to do in the past. They tend to focus on one sport and get very involved in training for one particular activity. And that's the group where the ACL and other injuries to the knee has become more prevalent. But also I see a lot of older patients that want to keep active and keep doing perhaps some lesser twisting and turning sports but still get similar injuries as they get older.

Dr Gavin Nimon: 3:54

Okay, have the incidents increased over the years? People seem to think that they have with the high level sports, or is it about the same?

Dr Will Duncan: 4:01

In Australia they looked at it. It's gone up about 5 percent per year increase in incidents. In males and a lot more perhaps in the females. And female athletes and females participating in sports have become a lot more common, particularly in higher impact and more aggressive sports such as rugby and tennis. Football and soccer, rather than just the netball. So the incidence females has gone up quite a lot.

Dr Gavin Nimon: 4:29

And is there a difference between female and male in the gender difference and the actual incidence of cruciates? I mean are ladies more likely to get it because of the size of their Cruciates or their relaxin hormone that may be in their system?

Dr Will Duncan: 4:40

Yeah, and there's a lot of theories about it, but certainly Sport for sport, the female athletes will have about four to six times as many ACL injuries as men. That's just looking at the ACL side of it and that does translate a bit to other ligaments. And the theories behind that are like you say, a different sort of anatomy in a female patient with a narrower notch around the ACL so it gets impingement in the knee and Also, the leg is a bit more valgus, so they're a bit more Knock Knee-ed. So that can potentially lead to more stress through the ACL playing sports. They've got a wider pelvis, they've got slightly reduced muscle bulk around the hips and the quads, and that's thought to lead to less protection of the knee during sport. And then, yeah, of course, the hormones as well. We're recently looking at a study here, of time of ACL injury and ovulation cycle in female athletes. It is indicating that there may be more ACL injuries around the time of ovulation.

Dr Gavin Nimon: 5:50

That's interesting stats. Is that something you could actually adjust? I can't imagine you can actually have a day off.

Dr Will Duncan: 5:57

Yeah, well, I think they are already looking at high level athletes and oral contraceptive pill treatment without regulating their monthly cycle so they can miss ovulation and perhaps miss out on getting increased risk for ACL injury and not letting them train or reducing training and activity levels during ovulation. So they're starting to look at it but there's not hard evidence behind it yet, it's still in the research stage. But yeah, it's a worry that sport for sport, there's such a big increase in the female population.

Dr Gavin Nimon: 6:37

And we started off with cruciates of course, but that's probably the predominant one you'd see as a surgeon, but what is the most common injury? I would have thought that medial collateral ligaments are probably slightly higher than ACLs, or is ACL more common than MCLs?

Dr Will Duncan: 6:51

Yeah, no, I think I think you're right. The the most garden variety injury on the sports field to a knee is MCL or medial collateral. The ACLs are, they are increasing because of, a number of reasons such as media attention and general community awareness and MRI scanners being available more readily than they used to be. So, we're seeing a lot more ACL injuries, but , they're about one in 2000 in the population, the ACL, whereas the MC L's probably 10 times that. And the other ligaments around the knee, the lateral and PCL or posterior cruciate, about 10 times less than the ACL. But yeah, certainly the biggest ligament injury, the knee is the medial collateral. injury. Unfortunately, they do heal up really well with nature. They're embedded in a lot of soft tissue. They've got a good blood flow and if you support them, they'll heal really well with a brace. Whereas the ACL, it sits in the middle of the knee and it has synovial fluid all over it, so it can't form a blood clot or scar tissue very easily and all the nutrients get washed away every time it tries to heal. So most ACLs don't heal very well with conservative therapy and end up needing a reconstruction if the knee is unstable.

Dr Gavin Nimon: 8:15

And what about the combination injuries too? Obviously lateral and posterior cruciates go together as do the anterior cruciate with MCLs and what, and there's also associations with meniscal injuries too. Perhaps you can outline what you generally tend to see as well in your practice.

Dr Will Duncan: 8:30

Yeah, I mean what you like to see with an ACL is an isolated injury because they have a lot less collateral damage in the joint and a lot less damage to the meniscus and the chondral surface, so if it's an isolated ligament injury and you do a good operation and they have good rehab, they can usually have lifelong good function in their joint. But they're not always isolated if you're aware they've The most common injury with an ACL is a posterolateral meniscal tear and also lateral compartment damage because the lateral side of the knee gets compressed as the knee pivots out of joint. So, you do get lateral side of compression and MCL sprains with ACL injuries and that can lead to cartilage damage, chondral damage and meniscal damage which then progresses later in life to osteoarthritis. So yeah, they're usually combined with some form of, an ACL is usually combined with some form of medial collateral sprain and a lateral sided bone impaction or meniscal tear. And as you said before, the lateral ligament injury is often combined with PCL damage just from the mechanism of force.

Dr Gavin Nimon: 9:51

Yeah, I always seem to think of the posterolateral corner as being more of a high trauma, almost like a motor vehicle accident type of injury, while the other combination of ACL and MCL being more of a sports injury. Would that be right or is there a, do you see the other lateral posterolateral corners in sports injuries as well?

Dr Will Duncan: 10:08

You see them in sports as well, but a lot less common. ACLs and MCLs, particularly ACLs, are usually an isolated injury. or a non contact injury. It's usually from change of direction or landing on an unsupported knee that gives way and there's usually no other athletes involved in the injury, whereas the posterolateral corner of PCLs, it's a direct blow to the knee, usually from the inside of the joint. So, you see it in motor vehicle or motor bike accidents, skiing injuries, high velocity injuries, and not so much in running sports, but occasionally rugby and things where you get someone, diving and taking out the legs, they might come across the inside of the knee and take out the lateral or posterolateral corner. So a lot less common and more associated with high velocity trauma and being flung from a motor vehicle.

Dr Gavin Nimon: 11:05

So what about the isolated meniscal injury, which we haven't talked about? Do they occur commonly? I know I sustained one when I was young, but I don't know if they're as common as I thought. How often do an isolated meniscal injury occur in a sports person?

Dr Will Duncan: 11:19

I don't really know the answer to that. I think you do see them. But usually in the sports patients that are younger, they've got really rubbery Meniscal tissue, it's not brittle and stiff and it does accommodate a lot of twisting and turning and impact. So to tear it, you need to have a fairly big force which in turn does cause other damage like ligament damage. So yeah, I think you're probably right unless they've got some underlying meniscal degenerative problem or a discoid meniscus which they're born with which is a big floppy lateral meniscus. Unless they've got those problems, they don't usually get isolated meniscal tears.

Dr Gavin Nimon: 12:01

So for the general practitioner or medical student coming through working in a GP practice and they see a person who's had an injury, what part of their history would you really want to isolate then? What do you focus on? I think you've already emphasised the importance of running in non contact injury versus direct trauma. Are there any other things you might want to take into account when you're assessing them before you go into the examination? And then we'll talk about the examination after that.

Dr Will Duncan: 12:24

I think on the history side of things with knee injuries it's about the pain and early mobilisation or weight bearing afterwards if they're able to get back on their leg and walk. Usually they don't have a fracture and that's one of the sort of rules for further investigation is if they can weight bear it's a good sign. The other thing on history is whether the knee felt unstable or whether the knee suddenly swelled up, which means that they've got bleeding in the joint and bleeding in the joint can mean fracture, but usually means an ACL rupture. So early sudden swelling and not being able to weight bear or get back on the field are usually good signs that they need further close assessment and they've probably got a fairly major injury, whereas if they can still walk, they don't get much swelling and they go back on and play the rest of the game, then usually they've got a more minor injury that may not need such close attention.

Dr Gavin Nimon: 13:24

So what, when do you come to examine a knee, what are the key steps that you look at when you assess them? Obviously we like to look for your move principle in orthopaedics, but

Dr Will Duncan: 13:32

Yeah, we're pretty simple guys, I think that's the main gist of all orthopaedics. With examination you wanna look at their gait. So that's pretty easy. When they walk into your room, you've already done half your assessment looking at, the alignment of the leg and whether they can weight bear and whether it's antalgic or whether it's just a normal gait. So from that, you can get a few little tidbits of, if they've got a really bent leg, or they're not putting the weight through, or they've got a flexion deformity, you know something's wrong. And that's really the looking, as well as looking for swelling, around the joint, if it's got a large effusion. And, usually they're acute injuries, so you won't see wasting of the muscle at that stage, but you might later on. And then, obviously, feeling the joint for effusion, and tenderness, and warmth. And then feeling the ligaments for stability. There's a lot of different stability tests and some of them are fairly sensitive and specific and some aren't. So, if you look at, tests for ligaments and ACL in particular the pivot shift test, which is very difficult to do in a patient with an acute injury is very sensitive and very specific for ACL. The other tests, such as your anterior draw, can be a little bit confused with PCL and ACL laxity. And the Lachman, similar, can be a bit confused, but generally the PIVOT's the gold standard. And most knee orthopaedic surgeons can do those tests and get better at them, but they are quite a specific and difficult test to do in general practice.

Dr Gavin Nimon: 15:13

And that's obviously where you internally rotate the tibia on the femur. and go from extension to flexion I believe it's actually, it drops back and then actually reduces as you do the extension deflection.

Dr Will Duncan: 15:24

Yeah, so if you put the leg out straight and rotate it internally and put a bit of axial load on and a bit of algus, it subluxes the tibia off the lateral femoral condyle. And as you flex the knee up, it clunks back into position. And if they've got a pivot, they're, 98 percent likely to have an ACL, incompetent knee. Whereas if they've got a Lachmann or a anterior drawer, it's only sort of 60 percent likely to be an ACL.

Dr Gavin Nimon: 15:57

And when you're testing for a posterior cruciate, do you rely purely on a posterior sag when you assess?

Dr Will Duncan: 16:01

Yeah, pretty much. That's the simplest thing is put both knees up together at 90 degrees and see where the tibias are sitting. And if you've, Got one tibia sagging backwards, then that's a fair sign the PCL's gone. It doesn't tell you much about the other ligaments and postero-lateral corner, but it does tell you the PCL's loose. That's the easiest thing for PCL testing. There's a reverse pivot, which is nearly impossible. And there's an active quads test you can do and things, but probably just the sag test is the most reliable for PCL.

Dr Gavin Nimon: 16:37

And how important do you put on grading the actual laxity in the anterior and posterior cruciates? And what grading system do you tend to use?

Dr Will Duncan: 16:43

Like all, look, feel, move, we use 1, 2, 3 with most orthopaedics where 1 is minor, 2 is moderate and 3 is severe. And it can be measured in centimetres, like 1, 2, 3, or it can be measured in whether there's a little end point or no end point. It's really after a few years of experience. It's a good measurement if they've got a little bit of laxity grade 1 as opposed to gross grade 3 laxity where it's falling off the femur, particularly in older patients when you're working out whether they should or shouldn't have a reconstruction because As you get older, you don't need to pivot sport as much and twist and turn as much, perhaps as a younger patient, and you can put up with a Grade 1 laxity in most people. So that's when you're starting to grade to work out what sort of treatment you're going to offer.

Dr Gavin Nimon: 17:39

What about assessment of the collaterals then? Do you just do a stressing into valgus and varus, or do you do the bagpipe test where you place the leg under the arm? What do you find the easiest to do?

Dr Will Duncan: 17:49

I do place it under the arm, but I, and then support the leg. You've got to do it in a bit of flexion. If you do a, MCL or LCL test in full extension, all of the posterior capsule and PCL and ACL provide stability, whereas in a bit of flexion you take all that tension off and you get a true feeling. So, I find it easier to support the whole tibia Twist the knee from side to get a feeling of great laxity of the medial or lateral collateral.

Dr Gavin Nimon: 18:22

Right. Excellent. So, you've gone through, you've taken a history, you've heard the story of the person running and landing awkwardly from a jump, or changing directions, and you're concerned that the knee has swollen up acutely. And you've examined them and you feel there is some instability, perhaps on the medial and also on the cruciate. What's the investigation of choice? And how does it vary if they can't walk straight off? Would you do, in that latter scenario, would you do an X ray first? Or how would you progress?

Dr Will Duncan: 18:50

Yeah, I think X rays are a fairly important test for orthopaedic surgeons. We do like them. They're becoming less well less, you don't see as many of them in acute injuries because MRI is so available. They're the only really two tests that we see is X ray or MRI. I think the x ray is really good if they've got no weight bearing tenderness over the patella or the fibula. If they're over 50 and if they've got a larger effusion, they're probably the rules for getting an x ray. Other than that, it's nice to have an x ray to look at growth plates in younger patients and that sort of thing. But you don't have to have them unless they've got a major tender spot or they're older or they can't walk. So X rays are good and you can see some of the subtle findings for ACL in ligament injuries like avulsion, Segond fractures where the capsules pulled off or lateral impaction of the condyle. So you can see some of the, some bigger problems that are going on if they're there.

Dr Gavin Nimon: 19:53

For the listener, just outline exactly the location of the Segond fracture again. Like

Dr Will Duncan: 19:58

all things around knees and elbows and things, you've got the capsule which has some thickenings in it and some sort of small unnamed or sometimes named ligaments or thickenings in the capsule. And one of them's the lateral capsule of the knee that attaches just onto the tibia. It's not Gerdy's tubicle where the ITB attaches, but it's just above that. And there's some tight fibres which may represent the anterior lateral ligament, which is a ligament that runs from the femur down to the tibia, rather than the normal collateral goes to the fibula. And it's a thickening in the capsule there, and when you pivot, shift the knee and almost dislocate the lateral compartment, you can rip off the avulsion of that proximal tibia with a bit of the capsule holding it. So it's just above Gerdy's tubicle.

Dr Gavin Nimon: 20:53

And that's an association with the anterior cruciate ligament injuries.

Dr Will Duncan: 20:57

Always, yeah, always means the cruciate's been stretched beyond repair or ruptured completely.

Dr Gavin Nimon: 21:05

Now, obviously treatment may vary depending on when the patient presents and perhaps you can actually outline how it may vary. Certainly if they present acutely, it may be different to someone who's actually several weeks down the track. Does that make a big difference to yourself?

Dr Will Duncan: 21:20

Yeah, I think what the patients need to be obviously educated and well aware of what's ahead of them. And you don't want to operate on anyone for anything if they're not well informed about their expectations on their rehab, particularly with ACL surgery. or ligament surgery because the rehab's sort of half the problem and the surgery's the other half and if they don't recognize that or they don't have any idea about that then it can become a disaster after surgery. So a little bit of education is good. The old treatment for ACLs was wait until they had no swelling and full range of motion and You retested them and then operated when they were fit and healthy. Most people don't do that now because the ACL rehab early on promotes movement rather than stiffness. So we don't see the arthrofibrosis and stiffness problems by operating early. So most people want to get on and have it treated in a fairly timely manner because they don't want to wait three months and then have 12 months off. So if they've been educated and I always want to send them down to have a session with the physios for that because physios are good at explaining the rehab better than we are. If they've had an education session with the physios and they seem like they understand the problem and they can move their knee fairly well then I'd go ahead with early surgery. But if they're not educated or they don't seem to be aware or If they're a bit stiff, I would make them wait for a few weeks until they've got better educated and better movement. So then you've got the other issue is the collateral damage and meniscal damage and fractures. So, fractures and repairable meniscus injuries should be treated early. You don't want to leave them for a month or two to get movement. So, that might sway. If they've got that other collateral damage, you'd go a bit earlier.

Dr Gavin Nimon: 23:23

What about if they've got a fracture then, would you wait until that had healed then treat it or would you go in early in that scenario too?

Dr Will Duncan: 23:30

If it was a stable fracture you might leave it and treat conservatively till that heals, particularly if it's a crack around where you want to put a tunnel or put a fixation device for your ACL. But if it's an unstable fracture or displaced fracture then obviously you'd fix that and probably do the ACL. at the same time if it was possible to do that.

Dr Gavin Nimon: 23:53

What about the role of conservative treatment in cruciate injuries? Is that still a role nowadays in the current sports person or is that sort of going out the window?

Dr Will Duncan: 24:00

I think it's had a little bit of resurgence. There's a study out of Sydney on bracing in flexion for a number of weeks and then slowly getting their extension back because in flexion, the ACL. is not under any tension. And if you pick patients with perhaps high grade partial tears or people where the ligament's still sitting in a good position, then they are getting some of them to heal with that treatment. I don't think they're getting back to sport any quicker, but they may get away without needing a reconstruction. But the treatments, six or eight weeks, I think, in a flexed knee brace, using a scooter, to get around and crutches and then another six or eight weeks getting walking again and then another three or six months of physio strengthening. So it is possible probably with a high grade partial tear or a tear where the fibers are still sitting in a good position. In the past, it's come and gone a little bit, it's making a little bit of a comeback at the moment.

Dr Gavin Nimon: 25:33

Do people need to have a cruciate reconstruction because of to prevent arthritis or to prevent instability episodes, or what's the main reason that people present for a cruciate?

Dr Will Duncan: 25:44

Well, it's for knee stability. So, most people, if they stop playing directional change sport, probably don't need an ACL for cycling, jogging, swimming, daily activities. Some people are unstable even with daily activities, they can have bad shape of their bones, maybe meniscus missing or some slight damage to other ligaments, and they just have instability with daily activities, loading a dishwasher and walking around the kitchen. So it's all about instability. If you have instability, it causes pain and swelling every time it gives way, which then Restricts your lifestyle and also it causes damage every time it gives way. So if you get torn cartilage or chondral damage from recurrent instability, you'll end up with arthritis. There's two things. One is if you're really wobbly and unstable, good to have a ligament put in. If you want to play twisting and turning sports, then keep playing those sports. It's good to have a ligament put in. And To prevent arthritis, it's an indirect prevention. If you have a stable knee, you'll get less cartilage damage. And if you have less cartilage damage, you'll probably have less arthritis.

Dr Gavin Nimon: 27:07

So we've already mentioned in passing, the medial collateral is usually treated non operatively. Are there any role, is there any role for repairing a medial collateral ligament as well as when you're doing an anterior cruciate as well, or even isolated a medial collateral ligament injury?

Dr Will Duncan: 27:22

There is again it's a bit like the ACL, if your medial collateral's displaced so far that it's got no chance of healing, sometimes they can rupture and stick inside the joint or they can move a centimetre or two away from their attachment or they can get stuck up above a hamstring. So if they're very displaced and they don't look like they're in a good position then you might repair early. But most of the others will heal well with. Brace therapy. There's a good blood flow. If you get them early, they'll heal well. If it's late, there's no healing potential. So after six weeks, you've probably got to repair them. If they're loose,

Dr Gavin Nimon: 28:03

what are the different techniques for repairing cruciate? Is there any role for primary repair or is it purely reconstruction nowadays and what grafts would you use?

Dr Will Duncan: 28:12

So, yeah, there's a bit more on repairs coming out at the moment. Trying to put scaffold around the old fibres and suture. Most of those techniques involve stitches and tension devices across the joint anyway, which is a bit like an artificial ligament. They're showing a little bit of promise, but again, it's a bit like the conservative therapy. It's a bit unknown as to whether it's going to cure everyone or whether it's just a pipe dream. In the past, repair techniques have all failed and you've ended up having to reconstruct.

Dr Gavin Nimon: 28:48

What sort of reconstructions can you perform nowadays? Are they still using hamstring grafts? So there are other items you might use or other Graft materials you might use for a reconstruction and how is it performed?

Dr Will Duncan: 29:02

Yeah, look, the the hamstring is still the most popular graft around the world and particularly in Australia. It was the patellar tendon graft back when we used to train and do orthopaedics in the public hospital. And that swung towards hamstring because of donor site morbidity more than anything. People thought the hamstring scar was a bit easier and the rehab was a bit easier. Patellar tendon harvest potentially has a risk of patellar fracture and patellar scarring and weakness and difficulty kneeling, so people went to the hamstring. Over time, people are swaying back towards patellar a little bit more because of failure of the hamstring grafts, and that was probably more from using two hamstrings, gracilis and Nowadays, the most common thing is to use just the semi T and quadruple it, and it's a very strong graft. It's twice as strong as a patellar tendon graft the day it goes in, but it does take a little bit more time to heal to the bone. So most people, probably still about 85 percent of people in Australia, use hamstring donor from the patient. About 10 percent probably use patellar tendon and that's becoming more popular. And quads tendon, so taking from the distal quads is a few percent and is gaining a bit of popularity because it's a little bit less destructive than the patellar tendon. And so patellar tendon grafts, quads grafts, you've got peroneal tendon from the lower leg which has come out of Asia. They have a lot of multi ligament injuries over there and they need more grafts to fix their multi legs, and they take peroneus longus, which we do use a bit for revision surgery these days. ITB is an older graft, it does leave a big defect in the leg, so it's not commonly used, but most people using autograft, so graft from the same patient, and most people still using quadruple semi tendinosis. There are better bone bank and cadaver grafts available. So, initially they were irradiating and treating the grafts to make them sterile, which killed all the good properties of the collagen, and they were never very good. Nowadays they can freeze dry the grafts without upsetting the collagen too much. So donor grafts are making a little bit of a resurgence, but they do have the theoretical risk of not incorporating quite as well and high failure rates. And infection risk and yeah, of course synthetic grafts.

Dr Gavin Nimon: 31:53

What's the advantage of the quadriceps tendon over, say, using a hamstring tendon?

Dr Will Duncan: 31:56

It's just a different donor site with donor morbidity from the front rather than the back of the leg. The tissues all very similar, whether it's hamstring, quads, patella, or. Peroneal, it's all your own collagen and it's all very strong when you put it in on the day but as the body incorporates the graft it gets very soft for a few months between three and six months and then it turns back into a living ligament by 12 months roughly. So It's just a good scaffold for the body to heal around. There's no huge advantage in one over the other. It's just what you believe is less of a donor risk, I guess, for the patient, and what you believe you can do to fix it into the bone. So you need to fix the graft in very strongly so the physios can do their early rehab.

Dr Gavin Nimon: 32:50

Right. What about Is there a different graft you might use for a female versus a male athlete, or do you use either the same?

Dr Will Duncan: 32:58

No, pretty much the same. And the latest, trend, I guess you'd call it, is looking at supplementing the graft with extra capsular tenodesis or tightening of capsule around the lateral side of the knee to try and prevent re injury and try and prevent pivot shift type mechanism in the knee. So that's become a little bit of an augment using a bit of biceps or other tissue to strengthen the lateral side of the knee. Sort of belt and braces technique.

Dr Gavin Nimon: 33:32

What about the the whole role of actually using a dual type graft where you try and reproduce the different fibres of the ACL, anterior and posterior fibres? Is that still back in vogue?

Dr Will Duncan: 33:42

Not really. The ACL, the ligaments made up of hundreds of different fibres. Fibers all at different angles and they generally classified into two bundles Antero-medial, Posterolateral. The Antero-medial provides a bit of AP support and that Posterolateral some rotational support and there was a stage there where a lot of people tried to do a double ACL reconstruction to reconstruct each bundle. But you did end up with, twice as many tunnels and twice as many fixation devices in the bone. And twice as more chance of not hitting the right spot or if you failed the graft or they re injured it, it was very difficult to rectify the problem. So, there was, a lot of enthusiasm for it, but technically it was really difficult and if it failed it was difficult to repair again. So most people have gone back to a single bundle.

Dr Gavin Nimon: 34:39

See, there's obviously lots of different ways of doing things. For your steps, for your doing your standard graft, can you just outline in brief terms how you would actually, what are the major steps you would do?

Dr Will Duncan: 34:52

Well, obviously, after you've consented and got the patient off to sleep, it's you first want to do an examination under the anaesthetic to confirm 100 percent that the ACL has failed and that is your pivot shift while they're asleep. It's a lot easier to do when the patient's asleep. Then you put the scope in the knee and check that the ligament is definitely torn. So you want it to be loose and you want it to be torn before you start harvesting or doing anything else to the joint. Once you've seen that it's a definite ACL rupture then I would take my graft next so that I could measure the size of the graft and we take out the hamstring semitendinosus and prepare it into a quadruple stranded graft with the fixation devices of your choice and then measure the thickness of the graft You then prepare the notch and remove old broken ACL fibres and clear out enough so that you can see where to put the new graft and it goes exactly where the old one was Drill a little tunnel using some guide wires and then put the graft in and lock it in place so that it's under good tension in the knee but not restricting knee movement. So it's got to be full movement with good stability at the end of the case.

Dr Gavin Nimon: 36:14

And you lock it with a button over the top of the front of the thigh or screw down the middle of the tunnel that you have drilled ? How do you tend to lock the graft in?

Dr Will Duncan: 36:21

I've been using a system that has a screw top and bottom for the last five or six years purely because that system has a strong fixation to the bone, so it allows that early rehab. The buttons are also very good and very popular.

Dr Gavin Nimon: 36:39

Post operatively though, do you need to use a splint not everyone uses a splint obviously, but do you use a splint at all and how long do you use it for and does it give any benefit?

Dr Will Duncan: 36:47

Look the splinting, the early stages after most surgeries and particularly ACL is getting that heat and swelling down, getting your wounds to heal and then getting a bit of gentle movement going and you can do all of that without a splint. if it's an isolated ACL, but often their leg muscles shut down, so they have a floppy joint, particularly if the anaesthetist have given them a block. So if they've had a block or they've got no leg control, we usually put them in a straight leg splint for a few days, just until they've got a bit of leg control and muscle activity, so they don't trip over and collapse on the leg. After that, a splint doesn't really make any difference to your healing unless they've got medial collateral damage or lateral damage and you've done other repair work in the knee. So, splinting is not necessary. It doesn't really protect the knee that much, except in those early few days. Having said that, the younger school kids are a little bit unreliable. Wanting to go back to the schoolyard, we'd put in a hinge brace for six weeks. Mainly to let everyone else know that they've had something done and to let them know that they've just got to take things slowly. Just so they don't get tripped over carrying their bag across the oval.

Dr Gavin Nimon: 38:11

And then of course, once you've gone through the surgery, you've put them, got them back to home, the rehab starts. And you already mentioned that the rehab was already started prior to surgery, but what's actually the main steps of rehabilitation? That may vary. Between surgeons too, and also depending on the physios, but what are your main key things that you want to work on?

Dr Will Duncan: 38:31

Well again, my key thing is avoiding aggressive activity early on. So getting the swelling down, icing the knee and resting the joint. To get the little wounds to heal up is the number one goal in the first week or two. But at the same time, getting some gentle movement. So the chondral surface gets its nutrients from movement and synovial fluid and the knee will stiffen if you don't move it early on. So gentle movement without walking around too much and swelling reduction is the first few weeks. By six weeks, they've got to get their legs straight. And a lot of people think they'll do that later on, but if you don't straighten a knee early, it'll stay stiff . And, at six weeks they're starting to walk a little bit more, provided their swelling's not too bad, and they're starting to do some strength work with the physios in the gym, and they push on with that in controlled situation with the physios until three months. At three months, you're looking at returning to light jogging. There's no race to do that, they've got to have no swelling and be comfortable and have a bit of muscle power. And then at six months they start looking at running and then nine months more directional training and sport training at around 10 11 months and you try and hold them off as best you can till 12 months because there's no test to show that the graft has healed or not. So you can test them for strength and you can look at them for, stability and swelling and comfort, but you still don't know if that little ligament's healed inside. Most of them are probably healed by nine months, but not all. And by 12 months, even more of them are healed. So less chance of it re rupturing if it's nice and strong and it's turned back into a normal ligament.

Dr Gavin Nimon: 40:31

Where do you think things are heading in the future for cruciate reconstructions and ligament injuries in general? Is there any new technologies that's come on the horizon? It sounds like there's already been a lot of advances over the years, but what's the way things are heading?

Dr Will Duncan: 40:45

I think all areas of medicine, people look towards stem cell type treatments and artificial scaffolds. They occasionally try things but they don't quite work. They add in platelet therapies or clots into the old ACL stump to try and promote healing. Eventually they'll probably be able to come out with a scaffold that's strong. That can fix to the bone well and can turn back into a living ligament, but at the moment it's not there yet. So, the only thing that really turns back into a living ligament is some of your own collagen, reliably. But maybe we'll come up with a better scaffold with patients own stem cells or platelets down the track.

Dr Gavin Nimon: 41:32

Now I believe, the final thoughts were, I believe the Australian Orthopaedic Association has got a anterior cruciate registry started, is that correct?

Dr Will Duncan: 41:41

It's a very difficult project to fund. The joint replacement registry is easy to fund because there's more money in the prosthetics. The ACL funding is, limited at this stage and I think we've definitely done some pilot studies. The funding, I don't think it came from the little implant companies because there's not enough money or profit in those implant companies, but there was some funding for it. The problem was that the patients they're not itinerant, but they travel a lot. They move around a lot. They're mainly young teenagers and early adults who move with work and jobs and unis and they're very hard to track down. And so even in the pilot work, we're only chasing up 50 percent of the patients that we've operated on. And unlike the joint registry that looks at failure and revision. There's a lot of people who fail their ACL reconstruction but don't come for revision, so there's a lot of issues. The patient's quite mobile population, there wasn't a lot of funding and revision as an end point's not the most ideal thing, so I think they've done the pilot work and we're still pushing to try and get more funding and try and revamp that and do a better job of chasing them up, but it hasn't moved any further as I know just yet.

Dr Gavin Nimon: 43:04

Right. Well Will, it's been fantastic hearing about the latest thoughts on cruciate reconstructions and ligament injuries in general. There's so much more we could go into, but I think we've covered a lot of ground today and we'll leave it there. Thanks very much for coming on Aussie Med Ed, and it's great to hear your thoughts.

Dr Will Duncan: 43:21

No worries, Gav. Thanks for having me. I hope that some of the students can learn a little bit, or a few bits of knowledge.

Dr Gavin Nimon: 43:29

Oh, it's been fantastic having you on board, so thanks very much. Thanks again. Thanks

Dr Will Duncan: 43:34

No worries. See ya Gav. Good luck.

Dr Gavin Nimon: 43:36

See ya. Thank you very much for listening to our podcast today. I'd like to remind you that the information provided today is just generalised advice and may vary depending upon the region in which you live, practising or being treated. If you have any concerns or questions about what we've discussed, you should always seek advice from your general practitioner. I'd like to thank you very much for listening to our podcast and please subscribe to the podcast for our next episode. Until then, please stay safe.