3D Printing for Lower Limb Salvage

Hello, thank you for allowing me to speak on the 3D printing for limb salvage.

Ankle.

3D printing is also known as Additive manufacturing and can be used to 3D print anything from plastics to ceramics.

And even to living cells, and all the pictures shown here are all items that were printed.

This complex geometric shape could only be created with 3D printing. Standard manufacturing would not allow for such.

To be generated 3D printing has been applied in Medicine for quite some time, with the early uses being anatomic models to allow for understanding of surgeries. The military has employed CT scans on all US military soldiers so that tissue and organ fabrication drug doses for some.

Uh, medications are now 3D printed to allow for a exact dosing of these medications that are patients. And in the orthopedic world, we're using it for custom instruments.

An implant.

If you look at this case here, uh, uh, this is shown by my colleague, a patient who ended up with a 3D, with a, uh, uh, triple arthrodesis, who then had,

Using a CT scan, you can have, uh, jigs created that are,

Which can be applied fairly quickly to the patients.

Allowing for much quicker surgical,

And, uh, and savings of time in the operating room, allowing for a total angle to be placed 18 to 20 minutes faster than without these 3D.

Here's a patient with a bunion that's complex, with a rotational,

And using 3D printed jigs and a 3D printed, you can then create this osteotomy performance fairly quickly in a very exact.

And get the correction that you require and desire to get the patients the way you would like. Here's a patient with ankle Arthritis that's fairly mild, but with a supra malleolar deformity, using 3D printing will allow us to place the osteotomy exactly where we want it, allowing for a 3D printed cage and a plate to be applied to allow for a fixation that's stable. And although it is slightly embarrassed now, it is much better than where it was, allowing for this patient to,

ankle.

Metal implants have been 3D printed for years now, and this allows for complex geometries to be printed with metal to replicate bone. And there are current options that are off the shelf that allow us to do some very, uh, complex surgeries with results. And so, here's a patient who had a flat foot reconstruction with a cotton and Evans wedge to allow,

Deformity to be corrected. Here's patients whose flat foot deformity was so bad.

The subtalar wedge was placed, allowing for that hind foot to be removed out of valgus and allowing for.

The loss to be performed.

But the real beauty of 3D printing is for custom implants, where we can do some very novel things limb salvage. And most of the implants that are currently available take inspiration. This company's implants use a honeycomb pattern that is replicated in the honeycomb bees. This, uh, this company takes in, uh, inspiration from engineering concepts concept.

And this company takes inspiration from the waves of the of the ocean using a wavy body uh on.

Now, uh, using electron beam melting, it's been shown that titanium implants allow for robust, uh, uh, bone ingrowth compatible. And so the real challenge for us in Foot and ankle is to try to span large bony gaps, and we can do this with old techniques of allograft, vascularized grafts, but these custom scaffold metal implants in the game.

And if you look at the literature with cases of non-3D printed trabe implants that have successfully gone on to allow for fusions to occur and uh improve.

but some of these novel 3D printed custom, uh, implants.

So, here's a patient, uh, from the west, uh, eastern part of North Carolina who had multiple surgeries on the midfoot, has, uh, navicular osteomyelitis, uh, and a vascular necrosis, and he comes in with his, uh, telling me that his surgeons have given him the option of amputation, um, a, a vascular pedicle graft with a fusion, and, uh, I offered him. And so, the first step is to go in, put an antibiotic spacer, debridement,

Antibiotics to clear the infection. In the meantime, we start planning the bone void that it needs to be filled, replacing the navicular with a cage, but allowing for, uh, a fusion to occur at a TN and joints. And so we and, uh, we get, uh, the, the, uh, patient back to the operating room, take out the antibiotic,

Uh, this is what the like. Uh, we've decided to make appropriately pack it with, uh, cancelllus bone, uh, infused Bone Marrow aspirate, so that it becomes a very bio,

Applied in the site and, and placed these two screws that have been planned, uh, into, into the ka form and into the talus and he goes on to uh heal on this side is back to providing care to his patients.

And has an active lifestyle in his limb. Here's a 12 year old, uh, here's a child who had shot himself when he was a 12 year old and, uh, take out, took out a chunk of his first metatarsal. Now, as he continued to age, his lesser toes continued to grow, and he ended up.

Uh, a, a, a metatarsalgia type scenario. And so you can see his preoperative films on the left here, um, stage one who went in and, uh, cleaned out the non-union site, placed the spacer, an external fixator, and, and distracted the length.

In the meantime, we planned for a cage that a 3D printed cage that's.

I can, uh, fill the void, pack it with graph just like the Other. This child is now 20 years old, has gone on to successful fusion, plays baseball recreationally, and, uh, walks through the cities of, uh, of the US, uh, with no Pain whatsoever.

Here's a patient who arrived to my office with an infected ankle Fracture, uh, that, uh, went on to a, uh, uh, a nonunion of an ankle fusion that got infected.

And, uh, just like the Other case, we brought him to the, the hardware, placed the antibiotic spacer, cleared out the infection antibiotics. And in the meantime, we created an implant that I call the Death Star,

Which is a, uh, spherical caged implant that allows for an intramedullary nail to be applied through the calcaneus tibia, allows for, uh, some, uh, uh, in the cage.

And we can go on and have these patients have limbs, their limbs salvaged with an ankle fusion that's successfully, uh, performed with this cage, the Death Star, and, uh, we basically wait for these patients to heal their wounds before we weight bear them. We do not need to wait for a full incorporation. So these patients can wait weeks, and that's a game changer. Here's a patient who came into my office, 32-year-old male smoker, 2 years prior to seeing me.

Had an opened, uh, open tibia Fracture that was exfixed, then rotted, then a hardware was removed, and he was discharged from the Other surgeon's practice, stating he could Return to work. Well, he comes in to see me because he can't walk appropriately, and this x-ray looks like he may have a little bit of plantar flexion or flexion at that nonunion site. Look at this more closely and you look at the Other views, you see that he's in a tremendous amount of varus and, uh, he's got some big problems here.

and we remove the, uh, all the hardware, debris the bone, uh, get an antibiotic spacer in there, put on. We have the plastic surgeons put a. Um, we, we actually get him to quit smoking. He, uh, gets 6 weeks of IV antibiotics, gets a 4 weeks, and we create this custom cage, pack it with nail down.

And 4 weeks after Surgery, he is walking. Uh, he is now fully healed. He is approximately 4 years out from Surgery, back to gainful employment, back to an active lifestyle,

Here's a 60 year old female who's 6 months after this hemi implant comes in to see me with a lot of Pain, inability to walk, and, uh, really just wants it taken out. And if you've ever been in this scenario before, you know that doing a bulk allograft, um, an intercalary allograft is very challenging.

Patients. And so what we can do here is plan the Surgery with cutting guides that are custom placed to allow for flat cuts to be placed on the, uh, first MTP.

Holding that joint in proper alignment when we make that, those flat cuts, and then allowing for a 3D printed cage plate to be designed such that it spans the, uh, bone void that we had created and also allows for a plate to be applied over that dorsal aspect of the first MTP allowing for effusion through the cage with the, with the, uh, MTP in appropriate alignment. And this.

Goes on to feel full fusion and is back to an active lifestyle and a bed and breakfast that she owns, allowing her to care.

Here's a 16 year old female who comes in to see me with a history of an ostochondral lesion on the tibia. It's a central lesion affecting her, her ADLs, and this is a challenging place to try to affect, uh, or, or, uh, treat an osteochondral,

So, I took her into the operating room, did a surgical arthroscopy. There was no cartilage disruption that I could appreciate, and extra-articularly did a bone graft, and, uh, the patient did OK for 8 months. But back to see me with increasing Pain with activities of daily living, unable to perform, uh, impact activities with gait. And you see here on her second MRI, there's an evolution and continuation of the process.

Now it's pretty apparent that she's got a, a cartilaginous lesion that, uh, has broken through into the.

So we 3D print a custom guide.

To allow for an allograft reconstruction and replacement of this, of this, uh, osteochondral lesion, creating a, a pie type triangular piece with the apex of the piece ending in that osteochondral lesion. And so, you see on the right hand side, the first jig that allows me to do the, uh, cuts. Um, I make those and put on the next jig. It's, it allows me to make a horizontal cut. I take a guide wire,

Small piece out of the native tibia using a, a fresh frozen allograft. We use the same jigsaw.

The allograft, a piece that needs to be placed into the paper.

We place it in, have a 3D printed.

And here we have a fairly, uh, low profile plate that's almost at the joint, um, that holds the, uh, and this patient goes on to heal and back to playing sports. Here's a military soldier that had a, uh, uh, an officer shoot him accidentally, has an infection.

And we clear the infection, same story, get the wound closed, plan the device. This is what it looks like. It's a very complicated, uh, 3D printed implant,

We, uh, go in, take out the cement spacer, prepare the receiving, uh, bone, in inside the appropriate implant, hold screw, and he's back in the military enlisted.

Here's a 19 year old female with CML, exposure to prednisone, develops a vascular necrosis of the talus and complains of Pain. And if you look at this sagittal MRI, you can see that she has quite a bit of AVN, both in the tibia calcaneus and the talus.

Collapse. And so what we can do is plan for a 3D printed, uh, um, articulate that will allow us to replace that entire talus. And so here we take out the talus, uh, with the tailor neck first, followed by the tailor head, and then the body. We have a large void. You see it here on the left-hand side. And using scisors, we can place talus on the right-hand side. Um, and we get different size taluses that are, uh, provided to us by the vendor. We pick the appropriate size, we close it up.

And it's quite remarkable the amount of motion you can get both in the plantar flexion, dorsal flexion, abduction, abduction, and inverse.

Perspective, and you know that you affect patients' lives when the, uh, father calls you that holiday, uh, very thankful because her daughter, his daughter's back to the malls during the shopping. So, the question is how do these patients do? And we looked at our 1st 14 patients with 6 total and we showed that the total tails replacement does restore Taylor,

It also restores tailor tilt, that makes sense, and these are significantly uh.

And our conclusion was 3D printed total taillight can restore the height and tailor tilt in the setting of ABM.

And so then we were interested in looking at our function. So, this is 15 patients a follow up, and we found that all preoperative, uh, scores improved using AOFS scores in terms of Pain symptoms and,

And we concluded from this that treatment, uh, option for Taylor AVN, um, that, that total viable option here. And so, here's a patient with a total tals replacement three months out. She's actually box jumping against medical advice because she feels so good.

Into her life. And so, we get more complicated cases as time goes on. Here's a patient with AVN after a motor vehicle accident, complex ankle Arthritis. We can do a total talus replacement. Here's a patient with ankle Arthritis, talar AVN Arthritis, and we can do a subtalar fusion with a total talus and a total ankle. These are our,

Total ankle replacements. Here's a patient with, uh, cavari foot deformity with AVN, a large amount of ankle Arthritis and subtalar joint.

So, stage one, we put an external fixator on, put an antibiotic spacer, and then put this total ankle in with the subtalar fusion.

Go on to do well. Here's a patient who I took care of with a triple Arthritis,

Went on to a ankle Arthritis, had, uh, a total ankle replacement, uh, was, came back after follow up. That talus has collapsed, hastor AVN, didn't want to, so, we three printed a talus replacement, uh, allowing this patient to maintain their total ankle with a talus that was on top of a triple,

He's back to playing golf. Here's a patient, uh, who sustained a motor vehicle accident. This is her actual,

She's seen down in Atlanta and has a talus that's fully gone. Uh, it was extruded. The media mouth is extruded. She's limb salvage. And what we do is we perform, uh, uh, uh, a planning for a,

Replacement.

And this patient is back, uh, two years out, has, uh, returned to her life, has limb salvage and is having, uh, 1 to 2 of Pain. Here's a patient with a motor vehicle accident with a, uh, complex, uh, ankle Fracture dislocation. It was placed, although over time developing dissolution of the bone, osteomyelitis. We, we take this case on and, uh, we, we bring him to the operating room, clean out the bone. He's growing up.

And we plan for a total talus with an, uh, subtal and navicular,

So you see that we get more complicated as time goes on. He's gone, gone on to, uh, to gain full employment. So the question is, how are they doing? Well, we just, uh, looked at our 22 month follow up in 27 patients. There's no significant change in ankle range of motion preoperative compared to post-op, but their VAS scores are significantly improved. Their FAOS Pain scores, ADL scores, quality of life scores are all significantly improved. Their sports scores improved, but that was not statistically.

And so these patients overall are doing well. I have, uh, most of these patients are living at 1 to 2 level of Pain. I've got a firefighter who's back on the force, a patient who's playing 18 holes of golf 3 times a week, a patient who, who's won the senior games, and you've seen the video of the patient who is.

Um, the future for 3D printing is cells and organs, and that is not too far off in the future. We'll see that in our careers. So, in summary, 3D printing is the tip of the iceberg. Metal 3D printing is at the tip of the iceberg. We're, uh, uh, creating limb salvage for the patients who otherwise would have lost their limbs or been significantly affected morbid, uh, morbidity wise through standard old fashioned, traditional surgical approaches.

The, the possibilities are limitless and really just limited imagination. Thanks.