There's a slight change. The speaker of the next talk is going to be given by Kai Ming-Fu on minimally invasive adult deformity surgery indications and complication avoidance. Thanks, everybody, for having me. I am filling in for Praveen. These are my disclosures. So I think all of us are increasingly recognizing deformity in our practice in some form, especially in patients that are coming for more degenerative problems, and we're looking pretty hard for it, and we're trying to use deformity principles in our practice. And deformity surgery continues to improve and is applicable to more and more patients, older patients, options for patients with low bone density. There's more options now for sagittal plane reconstructions, including osteotomies and now hyperlordotic A-lifts. However, spinal reconstruction can entail significant morbidity and complications. There's significant muscle dissection, lots of blood loss, still complications, postoperatively from the trauma they undergo. Sometimes there's long operating times, higher risk of infection, long hospital stays. And unfortunately, not all patients are candidates for big open procedures. And, you know, we've been told to look at everybody's deformity and to treat everybody's spine, you know, individually and to assess them. But then, you know, we look at a deformity, and not every deformity should be treated the same. So not every deformity should be a T10 to iliac. And even if you have a minor deformity, you know, it should be taken into account in your degenerative planning, but it may not require a big open procedure. MIS has the potential to treat a lot of these more minor deformities or less deformities, but also offers deformity surgery options for patients that may not be able to have them by offering surgeries with less dissection, decreased morbidity, and potentially shorter recovery times and less length of stay. But there's some potential pitfalls with MIS for spinal deformity. First of all, there's surgeon comfort and expertise with the procedure. There has to be sort of an intertwine of deformity practice and MIS practice. I think there's a lot of technology coming into play, especially with navigation that makes that a lot more facile. There's also the concern about achieving arthrodesis over longer segments in deformity constructs. And finally, there's the concern about patient selection. And that's specifically in terms of the sagittal plane deformity. This has been potentially difficult to treat with MIS conventionally. It's often, you know, conventional wisdom that requires osteotomies for correction to near normal. And this is a significant issue in terms of planning whether or not MIS can be applied safely to a deformity patient. However, there's been a lot of advances, and Praveen, Juan, myself, and a number of others tried to come up with an algorithm to help with indications for MIS deformity. And this took into account both coronal and sagittal plane deformity in order to identify which patients may be best suited for an MIS deformity procedure. And this really, if you start at the top, it starts with whether or not your spine is fused or rigid. And if it is, then you basically cascade into the open deformity category. But if it's not, it's based upon different parameters of the sagittal plane, whether or not you can be treated with minimally invasive, really a degenerative procedure, which is class I, or a little bit more advanced MIS procedure in class II, or a really advanced MIS deformity procedure such as an ACR or a mini-open PSO in class III. So class I, this is an example. It's somebody with a very minor deformity with a traditional degenerative problem. And this is somebody that could be treated with an MIS technique. Class II is somebody with a more significant coronal deformity. This is somebody who has normal sagittal plane, does not require a significant amount of sagittal correction. And this is also somebody that could now be considered treated by MIS techniques, if you're comfortable with them and applying them. Class III patients are those patients with a more significant sagittal imbalance, in this case a high SVA, high pelvic tilt, and a significant mismatch between a pelvic incidence and lumbar lerdosis. This is somebody who also isn't fused, and so is somewhat mobile. And this is somebody who could be treated with more advanced techniques for the sagittal plane reconstruction in a less invasive form, such as, if you're facile with it, a lateral with an ALL release. And then finally, there's the class IV patients who have significant deformity that may be fused or rigid, and these are patients that would not best be served with an MIS technique currently, and MIS should be avoided in this situation. But with all the techniques out there for MIS, there are definitely some other complications that can arise. Often in deformity, it's difficult for placement of our instrumentation percutaneously. Navigation has definitely made it better in terms of being able to navigate pedicles that are not in the normal planes, which may also have rotation as well as curvature. This is an example from Praveen of a patient who presented with deformity, and he underwent a two-stage operation, with the first stage being a multilevel ALIF, and followed by percutaneous pedicle screw and rod fixation. So in this case, there was a navigation error with a misplaced screw, and it was caught in time with an intraoperative scan and replaced. But again, this is something that can happen even with navigation. So some things you can do are to maximize your navigation, and this is what I do when I do navigation is I use a CT scan. I do significant stabilization of the patient, so I minimize any motion. I make sure the array is placed properly, and I try to minimize the number of levels between the array and my working level. All this is common sense, but it can be somewhat difficult if you're working at L2 and your array is placed in the iliac. So oftentimes, I'll try to use a spinous process clamp when possible, and this may involve changing my incision from two sort of off-midline incisions to one midline incision with a minimum amount of dissection to be able to place the spinous process clamp. I also minimize the forces when placing my screws. I've changed my technique from my traditional open technique, and I use a more automated technique with a navigated drill and tap. And I also make sure that I plan my skin incision as well, and I start my navigation with the skin incision. And then I also make frequent reconfirmations of my accuracy because each screw can potentially change your overall alignment, so you need to check it relatively frequently to make sure you're not off, especially medial to lateral. And finally, you know, we still have the problem of PJK, and in this case, this is a revision that was done partially MIS. And at the upper levels, without inner body, there was a pseudoarthrosis. And so this is something that is definitely of concern in patients treated with MIS for MIS deformity. And again, I think the one thing to take away is that you need to make sure you optimize your arthrodesis and MIS deformity. If you don't have an inner body as your fusion site, I would recommend, obviously, posterolateral arthrodesis, and that could be done either via tube. We do that navigated in my institution. But we definitely recommend posterolateral in longer constructs when there aren't all inner body cages. So in conclusion, proper indications, planning, and picking your patients will minimize a lot of complications in MIS deformity, as well as I'm a big fan of intraoperative imaging. I think this makes it a lot safer. So if you have that, employ it. You definitely can fix problems before you leave the operating room. Thank you. applause

minimally invasive adult deformity surgery

complication avoidance

MIS deformity procedures

surgeon comfort and expertise

arthrodesis