actually given me a lecture that was supposed to be entitled Failures of Navigation. And actually, my colleague who's not here, Terry Kim, said, you can't give a talk about failures. He said, we don't have failures. And I said, well, we have misfires sometimes. You can call them different ways. But yeah, we have failures and we have complications and things like that. And this is me, the cowboy surgeon, in a lot of ways. We have some navigation workflow research work we do. Actually, I'm just going to go to some of these things. You've seen some of this when I gave that talk. But here's another one, is that when we do some of this human factors analysis, when you've got a lot of people in an operating room, and this is a cardiac room, which our operating rooms aren't much different, you know, here's what happens. Put the screw in the wrong place. Why do failures happen in spine surgery and why do failures happen in image-guided spine surgery? And why do you end up with cases that look like this, that clearly are in the wrong place? Okay. So I'll go over some of these. Here's another case. I'm going to go back over these, but I'm just going to kind of flash by these things, because I can guarantee you we have complications and we take patients back. In fact, I had an incredible day in the operating room yesterday. I was supposed to have two cases turned into four, because two of my cases from Tuesday I brought back. What a great day. One's a thoracoscopic image-guided case that had a CSF leak. Okay, that's the surgeon. And the other one was an anterior cervical for an artificial disc, and the patient came back with a hematoma. That's bad luck. So anyway, so these are just some cases, okay, that I want you to look at these things. And the reason that this case shows a pedicle screw in the patient and it shows a wire is because this was one of these little MIS cases. I had done ALIFs. This is a rabbi from Los Angeles that I've known for years and taken care of some other spine problems, and he finally came up with a fusion, a need for a fusion, because he was collapsed and he had a foot drop and severe back pain, and so we did ALIFs on him, because I'd previously decompressed him, but he basically had one of these vertebrae that the pedicle is so big and the foramen is so small, when he collapses the disc, it squashes his nerver, okay? So it's an ALIF case. We ALIF him, that complete indirect decompression. I turned him over and we said we're going to do this real slick operation with bilateral wilts incisions, like I talked about for the MIS T-LIF case, and when I was putting the screws in him, a couple of them went in good and then something just didn't feel right, okay? Like I was breaking out of a pedicle or something wasn't right. So I said I'm going to leave these wires in and I'm going to do a CT scan and I want to see where the heck I am. So here you can see, here's a wire that's not in the pedicle. This one actually doesn't look too bad. Here's another one that's outside the pedicle. It's like, I don't know what's wrong. There's some of these things. You ever have a problem with this little device? Okay? It's supposed to be reliable, right? That's what this technology is. It's supposed to be reliable. It's supposed to work. But do you ever have to just boot the thing? I don't mean kick it, but do you ever have to just turn it on and off and it resets? I believe some of that stuff does happen with this, but I'm not blaming the technology. What are the causes of navigation errors? I think registration, that's complicated because you're relying on this whole system and I can tell you that measurements on CT scans are not always reliable. I've had cases where I've done measurements for various different reasons and then I've done things like put an artificial disc into a patient down at C7 who's got big shoulders and I relied on it and I put in the wrong size implant because you can't get the accurate measurements you think on CT scans. So don't rely on those things completely, okay? So you can register these things. The reference frame, we've talked about that. The reference frame is, I mean, that's probably 90% of all problems, but it really comes down to the surgeon, okay? The surgeon is the problem. He doesn't manage these other things right, okay? Especially the reference frame. It's where do you put this thing and how do you put it on and I can show you some of these other cases. How much time do we have? I don't want to take everybody's time. I've got a couple minutes? Okay, I better talk quick and then I'll shut up. Biggest problem in navigation is phase shift, okay? Here's a case, here's another case, okay? And this was that, and it all comes down to something wrong with your reference frame. That's what it is. We've got unintentional ones, we've got intentional ones. I mean, we correct deformity, we do osteotomies, we do corpectomies, we do all this inner body trialing and things like that, but these are reference frame, line of sight, instrumentation, patient movement, spine deflection or joysticking of it. I mean, we have lots of reasons that we can screw things up. That's really what it comes down to. Loss of tracking accuracy, misplaced instrumentation, free hand, do a repeat spin. There's all kinds of reasons, but it's surgeon frustration, yeah, we have that, too. This is a case that actually, it's a patient that had low back problems, she needed a fusion and she was going to get an A-LIF, and this was actually one of my partners had done it, and I'll just go through this case quickly, but it's one I've already shown you a little bit about. Is that, here's a PERC pin. This was back when we used PERC pins all the time. And so this is the problem, is that we had a PERC pin problem, and navigated, okay, we put all the screws in, and something, it actually felt good. Okay? It felt good. That's what I was told about this case, is that each of these screws goes into Kambon's triangle and goes into the disk space. So all three of them on one side, but something, the surgeon just said, something doesn't quite feel right, so he got a fluoro. So what happened here is that there was a rotation of, you'll see that there's a change in the end, and it makes for good novels, but I'm going to tell you the answer is the PERC pin was not the problem, but it was actually the attachment of the reference frame to the PERC pin. So we took the screws out, no problems, everything went well, we did the procedure, but here's a screw hole right here through this lamina. This patient never blinked, never had a problem. So anyway, counseled the family, went back, did the procedure, it's all done. Patient factors, don't blame it on the obesity of the patient. Inexperience of the surgeon, that's probably the main thing. But here's really what it is, is that the incision probably was too midline, and here's the PERC pin, and these are all the things, we tried to analyze why this went wrong, but this picture right here, okay, this picture right here shows you that there are two different orientations of the reference frame here, because it had those little ratcheting teeth on it that spring loaded, and so one of those somehow had been bumped in, it didn't change the trajectory of the PERC pin, but it changed the reference frame, and so that's why all three of these things came off. So what do we do now? We put a steristrip on that attachment where it can't be rotated. That's where the problem is. It's this thing, just simply how it was attached. So anyway, check the hex. So here's what I'm going to leave here. I looked up in PubMed, image guided spine complications. There were 300 articles about spine surgery, but not one of them said anything about complications. And so here's the best matches for image guided complications. Danielle, our paper was in that. Image guided spine, which was another group. And then there's one, Yang et al. So I looked at each of these, and none of them said anything about anything, even ours. But the only one that said we can predict medical complications in spine surgery, we can blame other people about medical complications, we're not medical doctors, but the take-home message is all about predicting medical complications. But here's my last. I'm going to close my talk here. This is our image guidance program that we do up in Seattle at the Seattle Science Foundation in November, and it's got all cadavers with every kind of technology you can imagine. So not to compete with the AANS, but we have a great talk and program that's in November. Thank you.

spine surgery

complications

navigation errors

CT scans

image guidance program