Joey Wahler (Host): This podcast is for informational purposes only and is not intended to be used as personalized medical advice. They're utilized for replacement surgery, so we're discussing orthopedic implants. Our guest, Dr. Lance Ho, he's an Orthopedic Surgeon for Skagit Regional Health. This is Be Well, the podcast from Skagit Regional Health.

Thanks for joining us. I'm Joey Wahler. Hi there, Dr. Ho. Thanks for being with us.

Lance Ho, MD: Hello.

Joey Wahler (Host): What are the most common surgical implant procedures that you and yours perform these days?

Lance Ho, MD: The most common is for trauma, meaning when someone falls and breaks a bone, and it could be any bone from the shoulder, even in the spine, down into the foot. And so that's the most common type of implants that we use. It's usually metal, and it's consisting of plates and screws often times.

Joey Wahler (Host): So speaking of which, we want to explain the various implant materials used. So first, what's the most frequent misconception, would you say, that patients have about the materials that are used in these procedures?

Lance Ho, MD: Patients oftentimes think that the metal is temporary. They think it needs to be removed. But oftentimes, we, they are put in and left in permanently and there's really no reason to remove them.

Joey Wahler (Host): And so, how do surgeons typically choose certain metals, plastics or sutures that'll be used in a certain case? How do you arrive at that?

Lance Ho, MD: The decision making is based on making the implant fit the bone and not have the bone fit the implant. So essentially, if it's a certain type of fracture or a certain type of procedure that we need for fixation or for the stability or for healing, we choose the metal based on the needs of the patient.

For example, the most common metal that's used for trauma is actually stainless steel. But it's now slowly being replaced by titanium. They're both very good metals. They both have time tested, and they both are very durable and very stiff. But there's different applications for either one, and we can go into more detail if needed.

Joey Wahler (Host): Yeah, what would be a couple of the factors that would make you choose one instead of the other?

Lance Ho, MD: So bone quality has a lot to do with it and also depends on the fracture pattern. For example, if it's a hip fracture the most common types of hip fractures that we're seeing now are what's called an intertrochanteric fracture, where they fracture below the head and neck. And that's oftentimes fixed with a titanium rod.

So there's no steel for that application. In contrast, if it's an ankle fracture, most ankle fractures now, many ankle fractures, can be fixed with stainless steel or titanium, but historically, we've used stainless steel, so that's still the predominant metal used for ankle fractures.

Joey Wahler (Host): How about nickel?

Lance Ho, MD: Stainless steel has a little bit of nickel, but it's less than 5%, and we haven't seen any allergies, really. For the most part, these implants have been put in people for decades and for probably over a billion people, I don't know exactly how many have been put in, but around the world they've been used internationally.

And so the risk of having a nickel allergy is actually, some people don't even believe in it. Actually, I haven't seen it to be honest. I've had some reactions to maybe metal irritating the tendon. Maybe the metal causing some localized swelling. Not sure if it's a metal allergy. Again, some people don't even believe that that's a real thing, but there is that potential that there could be a theoretical possibility of having a nickel allergy with the stainless steel.

But again, it's less than 5% in stainless steel.

Joey Wahler (Host): Gotcha, good to know there. So, how about plastics that are used?

Lance Ho, MD: Well, we touch plastic all the time. So as far as like having a reaction to plastic, it's almost unheard of. But we use plastic for example, when we have tendon repairs there's actually anchors just similar to drywall anchors that we put in. But these anchors have sutures attached to them and the anchors go into the bone and they have sutures that will tie into the tendon and pull the tendon down to the bone.

Anchors for like ACL replacements we'll use a combination of metal, buttons and also plastic anchors to hold the, um, collagen.

Joey Wahler (Host): You mentioned sutures there, Doc, so what should people know, if anything, about the materials used there?

Lance Ho, MD: So sutures come in essentially two varieties. One is absorbable and one's not absorbable. And the application is different. Oftentimes absorbable sutures are placed on the skin surface and that's more, very superficial. The non-absorbable ones are used for tendon repairs. They need to stay there permanently and we don't remove those.

The tendon, and tendons are basically made of collagen so the tendons will heal around that and will actually incorporate the sutures or actually grow around the sutures. So there's no reason to remove those non-absorbable sutures. And they're basically so strong, they're kind of like made of Kevlar like material on some of these sutures. They're basically synthetic, but they're so strong they can actually, as you're tying, you can actually cut your hand, because it's so rigid and stiff that it can actually cut through your skin.

Joey Wahler (Host): Okay, so as an example, one example, let's say someone's going for knee replacement. Typically, what would be the likelihood that they would be using a given material?

Lance Ho, MD: The majority of patients, I'd say probably greater than 80 to 90 percent of the patients, have a cobalt chrome knee that's on the upper part called the femur, which is the part that goes on the thigh bone is made of cobalt chrome. There's another metal in there, a couple other metals, it's basically an alloy for the femur part, the upper part. The lower part, the tibia part, which is on the shin bone, is made of titanium. So it's a combination of different metal that goes into a knee replacement. That's the majority. There are other types of metals. If someone has an allergy to nickel, we're even concerned about any potential allergies, we can go to a non-nickel product, which is all titanium, which does not have nickel. Or there's also another product called zirconium, which is heated metal to the point where the nickel is removed from that metal.

Joey Wahler (Host): Okay, so a surgeon may also use pinning, screws, rods or nails. What should people know about the differences between those?

Lance Ho, MD: So with the orthopedics, as far as the choice of implants, it's kind of like real estate. It's, location. Pins are essentially screws. It's been historically said that pins you know, you get a hip pinning, you're actually getting screws. So another misconception when people say this is more of a side when people say I have a fracture but is it broken is essentially the same meaning fracture broken crack. It's all the same meaning. So when you have a fracture just below the femoral head which is the thigh bone, it's just below where the ball and socket joint, we use screws, which are in layman's term, people call it pins, but we use screws to hold that.

If it's a fracture below the neck, which is that inner troch fracture we mentioned earlier, that gets a rod. And it's oftentimes that's made of titanium. The screws are typically made of stainless steel, but we also now have newer options with titanium as well. Either one would do the work or do the job. 

Joey Wahler (Host): Now, by the way, I think we should point out, Doc, folks, you heard it here first, that a break and a fracture are, in fact, the same thing, kind of like, I would imagine, a bruise and a contusion, right?

Lance Ho, MD: Yes. 

Joey Wahler (Host): Just a fancier way of saying it. A few other things, Doc. First, how about at an airport? Some people may be wondering, listening, if you're going through a building security or an airport checkpoint, will metal implants parts set off a detector?

Lance Ho, MD: I think that depends on two things. I think it depends on how much metal you have. So if you have one screw, it's probably unlikely. And if you have a knee replacement, a hip replacement, very likely it's going to set it off. And it also depends on sensitivity of these detectors. So I think those are the two factors that play in. Historically we used to get prescriptions and letters for people that would fly to warn TSA that they have metal, but now it's so common that people are traveling that have metal in their bodies that we don't even do that anymore.

Most of the time people would just go to TSA. They either get wanded with that wand, or they have to stand in that special scanner where they have to raise both arms, kind of like, holding a diamond shape above their heads. So that's that special scanner.

Joey Wahler (Host): So the bottom line there is not all airports are created equal and that could be a big factor in that scenario. How about, is there ever a time when hardware should be removed from a patient?

Lance Ho, MD: Yeah, I think if there's irritation of local tissues, such as tendons, if they move, for example, if it's in the wrist and they're moving their wrist up and down and they feel the metal, then we can remove it. If there's localized swelling specifically around the metal, sometimes it can happen.

And I don't know if that's related to a reaction to the metal or just the fact that the tissues around it are just not liking having this foreign body. Cause it is a foreign body. We will remove it in those circumstances.

Joey Wahler (Host): And then finally, in summary here, you've done a great job very comprehensively explaining all these materials. What would you say to people listening about the most important thing for patients to know, generally speaking about the materials going into their bodies for a procedure?

Lance Ho, MD: As a previous attending or mentor told me, it's not necessarily the metal or the implant. It's really the surgical technique and the recovery. So part of it is probably 80 percent of it is the surgeon, 10 percent of it is the patient as far as the rehab, and maybe even more than that maybe it's, you know, 60 percent surgeon, 30 percent patient, and then 10 percent of it is the implant.

So I would tell patients don't worry so much about the implant. As long as it's the surgeon's done a good job as far as making sure it's stable, making sure that it's a good construct or that everything is satisfactory, that's really incumbent upon the surgeon to do that.

And then the other part of it is the patient rehabbing and recovering and being compliant and doing everything that's asked. And then, the last part of it, just the choice of implants. So that's, the least part of it.

Joey Wahler (Host): So basically simply put, it sounds like you're saying, Doc, don't sweat the materials, right?

Lance Ho, MD: Exactly.

Joey Wahler (Host): Good advice indeed. Well, folks, we trust you're now more familiar with orthopedic implants. Dr. Lance Ho, very interesting indeed. We've learned, if nothing else, that a break and a fracture are the same. Thanks so much again.

Lance Ho, MD: You are welcome.

Joey Wahler (Host): And for more information, please visit SkagitRegionalHealth.org. Again, that's SkagitRegionalHealth.org. Please check the full podcast library for topics of interest to you. If you found this podcast helpful, please share it on your social media. I'm Joey Wahler. And thanks again for listening to Be Well, the podcast from Skagit Regional Health.