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Foot & Ankle International
FAI August 2025 Podcast: Trajectory of Recovery Following Total Ankle Arthroplasty Using Patient-Reported Outcome Measurement Information System (PROMIS)
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- [00:03]
A
This is Mark Easley and I have the distinct honor of talking to Dr. Sikoya, Charlton and Thordason. The paper is titled Trajectory of Recovery Following Total Ankle Arthroplasty Using Patient Reported Outcome Measurement Information System, or PROMIS. Dr. Anders Praskoja is in the United States Navy. He's the Division Head of Foot and Ankle Surgery Service at the Naval Medical center in San Diego. He completed his fellowship training at Cedars Sinai Medical Center. Dr. Timothy Charlton is a professor of orthopedic foot and Ankle Surgery at Cedars Sinai Medical Center. He's a native New Yorker, completed his orthopedic residency at St. Luke's Roosevelt Medical center and fellowship at the Hospital for special surgery. Dr. David Thorderson is Chief of the Foot and Ankle Surgery Service and Professor of Orthopedic Surgery at Cedars Sinai Medical Center. He is the current president of the AOFAS and and the former Editor in Chief of Foot and Ankle International. Dr. Saltzman and I selected this article to highlight this study tracking evidence based outcome measures in the assessment of total ankle arthroplasty over the first year following surgery. Welcome to the program. Andrus, Tim and David. So I'll get started and as lead author I'll ask you the first question. Would you please give the listeners a brief summary of your paper and its major findings?
- [01:16]
B
Mark, thank you for the opportunity to be here. We're really excited about this paper. In our study, we looked at the recovery curve of patients undergoing total ankle replacement Using PROMIS scores. We followed patients for up to a year and measured changes in physical function, pain interference and depression. We found that most patients can expect improvement in physical function and pain from pre op as early as three months, with the majority of improvement occurring within the first six months after surgery. By one year, the majority had returned to near normal levels for both pain and function. We also found that patients with worse preoperative scores were more likely to have a slower recovery. I believe these findings help set realistic, realistic expectations for recovery and can support early intervention for those at risk. I think it also helps to better answer key questions that many patients ask before and after surgery. When am I going to feel better?
- [02:08]
C
Great.
- [02:09]
A
Thanks a lot, Tim. I'll turn to you. You conclude the manuscript suggesting that your findings provide surgeons with quote unquote tangible data to set patient expectations. Have the findings of the study indeed changed your message and preoperative patient education for your patients with end stage ankle arthritis for for whom you recommend total ankle arthroplasty?
- [02:29]
D
Yeah. Thanks Mark. First time long Time. Love the show. I will say that it has. The paper is important in the sense of it answers that binary question, hey doc, how long is it going to take? And that's pretty much any preoperative consultation. The purpose of this paper is really to put a number to it and to use metrics to sort of really give a good guidance. I used to say that a total ankle is like a pregnancy takes the first three months in trimester and you go through that. But now you can really sort of say, well, you get pretty good at six months, but you get better at a year. And this is sort of a real tangible metric.
- [03:02]
A
Great. Thanks. Yeah, really. I've enjoyed reading the article. David, I'll turn to you. You and Andres and Tim mentioned that PROMIS scores are validated, but only a few studies have used PROMIS scores in assessing total ankle outcomes. Would you please give the listeners your insights on why investigators studying total ankle outcomes should use PROMIS scores?
- [03:23]
C
Thanks, Mark. Yeah, I'll give you an even more general answer. Yes, investigators should use PROMIS scores for evaluating total ankle arthroplasty, but hopefully they'll use PROMIS scores for evaluating all clinical outcomes. One of the biggest problems with clinical research in general is that there's just nothing really that studies have in common. You know, one study will use a ffi. Another, you know, we use the outdated AOFAS score. Some people use an SF36. And the beauty of the PROMIS scores is there's various subscales, three of which we use in this paper, that will look at things that are really relevant for orthopedic procedures, then you take that beyond that. You know, we've been focusing on patient reported outcomes for years now. But the beauty of the PROMIS scores is, besides being validated, is use computer adaptive testing such that instead of taking upwards of 90 questions to do an AAOS lower extremity and foot and ankle scale which includes an SF36 with five to seven questions the patient can answer with each question leading to a different question about their physical function, their pain interference or depression and get a score on each of those. So it's far easier for the patients, much less burden on the patients, your staff, and it makes studies comparable to one another.
- [04:33]
A
Perfect. Thank you. Andres, your study includes PROMIS score data for physical function, pain interference and depression. As you mentioned in the introduction and in your discussion of the paper, you mentioned that depression is underreported in the literature. In your discussion, you also briefly weigh the relative importance of these scores. If you had to Limit this study to reporting on only one of the three components of the promise scores included. Which of the three scores would you emphasize and why?
- [05:03]
B
Yeah, so if I had to emphasize just one of the three promise domains, I would probably focus on physical function. While pain and depression are important, physical function tends to be the most direct and tangible measure of how well a patient is recovering after total ankle replacement. It's also the domain where we saw the clearest trajectory of improvement. Practical terms, patients care deeply about regaining mobility and function and how that impacts their ability to walk, return to activities and perform daily tasks. From a clinical standpoint, physical function is more practical and can help guide rehabilitation, set goals, and identify those who may need additional support. That said, including all three provides a more complete picture, obviously, especially since pain and function can influence recovery. But if I had to pick one, it would be physical function.
- [05:55]
A
Perfect. Thank you. Tim, you touched on this already a bit and Andres just mentioned some of it too. But providing evidence based and objective data to educate patients on what to expect in the first year following total ankle replacement. You know, to me that's particularly useful and I really, I think this is a very important contribution to literature. So great work. The majority of my total ankle patients note improvement of what I think is the deep joint arthritic pain they have. But then during this first year, they focus on the lack of full range of motion when compared to their contralateral healthy ankle and the persistent edema, asking, when will the swelling ever go away? So in your opinion, how much do the lack of physical range of motion or physiologic range of motion and persistent edema influence total ankle outcomes in that first year? After total ankle, I think they do
- [06:45]
D
influence it, but I think a lot of that is preemptive education. If you look at the total ankle range of motion, it's a surgery that keeps what you have, not gains what you lost. So setting that expectation up front is very important. I think the same thing with swelling management is, hey, your ankle is going to be a little thick, a little cankly, that's pretty normal. And I think reassurance of that is in their normal range is important. I think it's all about expectation management. That's sort of a life lesson. If you say, hey, you're going to marry a rich orthopedic doctor who's going to be fantastic to you. And if you told that to my wife, she was like, well, I got you. So I think it's about expectation management.
- [07:28]
A
Well, I'll hope your wife gets a chance to Hear this podcast and very interesting analogy. I like it. Okay, good. Hope she does too. Let me take back to David. In the discussion you acknowledge the concerning attrition in collecting PROMISE scores with only a limited number of patients completing the physical function, pain interference and depression scores at the one year follow up. You also identify the issue in other studies using PROMIS survey. So a recurring theme that there's attrition in these follow up studies for your investigation were the patients lost to follow up or did they return and you simply were unable to collect the promised data? With your extensive experience in research and reviewing manuscripts, what recommendations do you have to optimize data collection?
- [08:16]
C
Well, Mark, you hit the nail on the head with the biggest weakness of this study. But as pointed out in our paper, our ballpark 50% overall follow up is somewhat comparable to many of the other papers that are out there. And I think the bottom line in this paper, the problem with our follow up is that this is prospectively collected data that was retrospectively analyzed. So these patients aren't lost to follow up. I mean, pretty sophisticated patient population. None of them are uninsured. None of them are even Medicaid medical type patients. They all have either private insurance or Medicare. A couple work comp. But what happens is in a busy clinic like mine, the nurses may not be motivated because there's obviously frequently a revolving door about who's actually in clinic and they'll sit the patient down. The patients either have a tablet or a desktop computer in every single exam room. And if the nurse isn't busy, they say, hey, can you do this? Well then the thing is, the patient may or may not actually complete it. Now, with my extensive experience doing research and reviewing manuscripts, the way to do this is do it prospectively because then we focus on this and then every patient comes in for total angle. It's like, hey, did you. I'll walk in and say, hey, did you fill out your questionnaire? Because it's really important we get that because I'll know we're looking at it. Otherwise, every single one of my patients, whether they're coming in for plantar fasciitis or an ingrown toenail, which I don't see, is going to be asked to fill out a promise score. I mean, and it's just impractical, especially when patients have vague pain. So unfortunately it just kind of falls the radar. So what we did was, well, it looked like there are a bunch of patients lost to follow up and I think we included patients up to 15 months after. But if it was after 15 months, we could have called them and found them, but we were past that one year mark, so it wasn't really going to fit in the time frame of the study, so we didn't bother. But I, I bet you I could. We could probably track down almost every patient in the study, right?
- [10:10]
A
Yeah. We follow our total ankle patients pretty carefully and run into some of the same issues. So I certainly was curious to see your answer and I agree with you trying to do it prospectively probably the best way, but it does a lot of work and a lot of extra work for your staff that's already busy. So I understand. Andres, you are the division head of the Foot and Ankle Surgery Service at the Naval Medical center in San Diego. Would you please share with the listeners, many of whom may not have a military background, what you consider the most rewarding aspects of your leadership responsibilities and, and your foot and ankle practice at the Naval Medical Center?
- [10:43]
B
Yeah, so I was recently appointed to this position. So it's a great opportunity and definitely still a lot to learn. But I would say one of the most rewarding aspects of my job is being able to care for those who serve our country. Our population of patients face incredible physical demands and make tremendous personal sacrifices. So being able to help them regain their function, needed to not only return to duty, but return to spending quality time with their family is especially meaningful from a leadership perspective. I've had a lot of great mentors in my training, two of them who are here today. So it's really a great opportunity for me to pass on all the mentorship I've benefited from to the next generation of surgeons. And there's really a deep sense of camaraderie and unity in military medicine that's hard to replicate elsewhere. So I'm just glad to be a part of it.
- [11:34]
A
Thanks for sharing your insights. That's a good always. I'm curious, so thanks for taking the time. Tim, you shared your post operative protocol with one month of non weight bearing, one month of advancing weight bearing in a boot, and then transitioning the total ankle patients to a lace up ankle brace. I don't routinely prescribe physical therapy for my total ankle patients, but as you suggested it in your discussion, I may consider PT for patients who appear to have a slower recovery. With that said, do you think that routine physical therapy may be useful in optimizing outcomes after total ankle? And if so, do you believe that PROMIS scores may be improved with routine physical therapy once the incision is stable?
- [12:16]
D
That's a good question. I think it's not necessarily a thing that's required. I think every patient in some degree wants to feel like they're empowered and they're doing something. My personal belief is in that second trimester month, 4, 5, 6, that walking in the pool, if they have access to a pool in Southern California, that they do often, I find it's like a poor man's altered G. If I can get them in the pool, and that's with Achilles or post hip tendons or anything like that, really, really helps from a rehab perspective. Early on I'm a little bit wimpier than Dave is. I'm trying to sort of, I'm more paranoid about the porous ingrowth, so I'm trying to optimize the bone ingrowth. So I'm not really rushing patients in a shear force. I'll let them axial load in a boot, but I'm trying to avoid shear because I'm thinking that it's going to sort of tear off that porous in growth a little bit. But if I'm going to initiate therapy in the first trimester of the recovery pool is the way to go and it really is helpful.
- [13:19]
A
Great. Yeah, thanks. I debate about that too, but I think we follow the same plan. Now. I don't routinely do it, so that's helpful. David, as former editor of Foot and Ankle International, you have a unique perspective on submission and acceptance of manuscripts. One obvious feature of this study is that it directly challenges the total ankle submission requirements of a two year minimum follow up for Foot and Ankle International and Foot and Ankle Orthopedics. Remember that Charlie Saltzman is the current editor in chief. He may have a very high curiosity on your answer here, but do you still support the 2 year minimum follow up requirement? And then also for this investigation, you discontinued collection of PROMIS data at one year. Based on your experience with total ankle, what do you anticipate the promise data would show at 2 years follow up?
- [14:11]
C
Great questions, Mark. So the bottom line is not only do I still support the 2 year minimum follow up requirement for ankle arthroplasty papers, but ideally. But it would really limit the submissions. It should be five years because when things start going sideways with ankle replacements, oftentimes it's two, five or obviously, as you know, ten plus years after the implants put in. The reason why I think it was permissible to accept our paper is that's not really what we're looking at. We're not looking at ankle arthroplasty outcome in total. What we're looking at is just the initial recovery following it. And what we found is these patients have really plateaued almost by six months, but certainly by a year. And it's certainly my clinical experience because I for my first probably 10 years of doing, I started doing ankle replacements again about 2007, somewhat routinely and do a lot of them now and I would have them come every single year. And I found that after a year they just didn't change, they were fine. And so I started saying well I'll see in two years. And then a lot of patients don't show up and I don't bother trying to track them down. But if problems are going to develop, for the most part I believe they'll come back and still see me. So absolutely two year minimum follow up. This was a very special subset. We were just looking at how do they do in that initial period after surgery. And since it basically is a done deal by a year, we just didn't bother going beyond that. Now my experience pop to your question though is what would I expect the tiers I would bet you that to your follow up data would be basically identical to one year. I really don't think there's an incremental improvement in the patient reported outcomes between those two time periods.
- [15:46]
A
Got it. All right, well thanks. Yeah, I know that's important question just because we like to think two year minimum is important, absolutely essential. But in this case I do agree with you that the information provided in that first year, that's really what we want to know and it's valuable to have that even though it may not meet that requirement. So thanks for taking the time and answering that. Andres, I have a tougher question for you. I don't want to burden you with it too much, but I'm just always curious about this because I don't have a background in statistics but I suspect that many of our listeners also lack dedicated training and statistical analysis. So in your methods you state to account for missing postoperative promise data, we performed a sensitivity analysis using a conservative approach of caring for the patient's preoperative promise score. Additionally, we compared patients who did and did not complete the one year follow up using a Wilcox and rank sum test for age and BMI and a chi square test for gender and laterality in simple terms that even I can understand. Could you please explain how the sensitivity analysis Wilcoxon rank sum test and the chi square test allows you with confidence to compensate for missing post op promise data?
- [16:57]
B
Mark, that's an excellent question and I'll try to break it down in a way that's hopefully accessible to all listeners. So when you do any kind of study like this, not every patient comes back for every follow up or not all data is collected at every follow up appointment, which obviously creates some gaps in the data. So in order to minimize how those gaps can skew the results, we ran what's called a sensitivity analysis, which basically assumes the most conservative outcome. If a patient either missed follow up or data wasn't collected at the time, we assume they didn't improve at all and carry forward their last recorded score. So if our raw data still held up under that assumption, and it did, then it gives us confidence that our findings are valid. As for the Wilcoxon rank test, it's really just a simple way of checking whether patients who followed up at one year were significantly different in age or BMI from those who didn't. So it really helps us make sure we're comparing apples to apples. And the Chi square test does the same thing, but for categories like gender or whether surgery was done on the left or right ankle. I think the takeaway point is we use these tools to sort of double check that patients who didn't complete follow up or promise scores weren't dramatically different from those who did. And this strengthens the reliability of the conclusions we drew from the data we had.
- [18:21]
A
Perfect. That's the best explanation I've ever heard of that. So thanks a lot. Yeah, that's very helpful because I'm always curious because the same thing, when we do our studies, we lose patients. So now I know what to do. I like it. Tim, correct me if I'm wrong, but I believe that you are originally from New York City and you now have been in Los Angeles for many years. So share with the listeners where is the place to be? New York City or la. And then also just a second question with that. After having trained with Bill Hamilton while in New York and carrying on his passion for dance medicine while in la, could you share with the listeners a favorite Bill Hamilton story?
- [18:59]
D
Yeah. You shared the script in preparation of this. That was the most enjoyable question to think about regarding Andres answer. I was told there'd be no math on this test, so I'm going to move forward. I do love New York. The coldest I've ever been and the hottest I've ever been is in New York City. I self identify as an upstate New Yorker, but after two decades in Los Angeles, it really is a pretty amazing city. It's a great food culture, great ethnic culture. There's tons to do. Everyone complains about the traffic, but that's pretty much because there's nothing else to complain about. And it really is a great city. I want to keep it as a hidden gem because everyone's going to move out here. But it's pretty great. Get to look at the ocean every day, but it's pretty great. As far as Bill Hamilton goes, it's sort of what's my favorite Bill Hamilton story? It's sort of who's my favorite child? There are so many and it just speaks to a long lasting legacy. And I was sort of asking Andres, I said, hey, what Bill Hamilton story? Do you remember me telling you? So his response was the Latin phrase. So here it goes. On day one of your fellowship, he'll sit you down before he goes into clinic and he'll tell you, I'm going to say something. Ut aliquid fieri videatur. Which in a Louisiana accent, you don't expect Latin. And ut aloquid fieri videatur means make it appear as if something's being done. And the lesson behind that is like, if you have a patient coming in and they have pain in the back of their heel and a big bump, it's insertional calcific tendonitis. You don't need an X ray. You can tell them what to do right before. But they expect a show and they expected a show. They traveled to see the show of King Bill Hamilton. So he would always say, listen, I'm going to give him the show, but I'm going to make it appear as if something's being done. So he would tell that and he'd say, in short, he goes, if you hear me say ut aliquid, then that means I'm just sort of making it up for the show. So he, you know, he'd have him walking. Your tippy toes, you see that Aliquid. And you'd have to sort of nod knowingly as a fellow and genuflect. And he would try to, try to get you to laugh because I mean, he'd be like, turn around, walk on your hands, spin in three ways. And you just, you have to play the straight guy. And he's like, see that? Eloquent. And you, yeah, sure, I noticed that. So that's probably, I mean, again, one of many. But the late Bill Hamilton, it's like a telling legacy. If people are still asking questions of what's your favorite story and you can't really decide, that's great.
- [21:38]
A
Well, thank you for the time. I know it's a little aside, but it's always good to hear. David Charlie appointed me as Foot and Ankle International Podcast editor, and I've really, really enjoyed this role, keeping in mind that I have a particular bias in favor of the Foot and Ankle International podcast. As former FAI Editor in chief, do you see value in the FAI podcast complementing each month's FAI lead article?
- [22:05]
C
Mark I can honestly tell you that the starting the podcast when I was editor in chief was probably my single biggest surprise as journal editor because I'd heard about these things called podcasts. I don't do any social media and I'm tech savvy at all, but it's like, okay, podcasts, we gotta appeal to younger people. Okay, we'll do a podcast and probably if you take an article like this, like we've done here today, and we delve into it, which is really cool, so you get a quick summary like Andres gave earlier, and then you really get to delve into some of the details. The paper that's really great. And probably, you know, 50, 75 people maybe will eventually log into it. So I was on the managerial board even for a while after I was editor in chief, and the bottom line is monthly. Eventually about 2,000 people download each podcast. So it is immensely popular. And I think it's an amazing addition for that one article, which when I did it, I'm not exactly sure what exactly Charlie does, but I always picked what I thought was the best clinical article because that's where our core readership, the OFS members, really want to hear about. And I think it's a fantastic thing. I think you're doing a good job too.
- [23:10]
D
Oh, geez.
- [23:10]
A
Well, well, there's a lot of pressure now. I didn't realize 2,000 people logged on. Holy cow. All right, I'll try to keep. Keep it as good as I can make it. Andres, back to the paper. In your discussion, you, Tim and David suggest that a potential study limitation is not including radiographic data. With your focus on PROMISE outcome scores, how would you include radiographic data in assessing the trajectory of recovery in the first year following total ankle arthroplasty? And moreover, aside from implant failures, do you think that radiographic data is really important?
- [23:44]
B
Yeah, that's a great point. And while our study focused on PROMISE scores to capture patients perspective on recovery, I recognize the value of radiographic data. If I were to integrate X rays, we'd likely use serial imaging both preoperatively and postoperatively at key time points. To evaluate for things like preoperative deformity, but also postoperative alignment, component positioning, evidence of bone integration and lucency. And so pairing that with PROMIS scores could help us explore correlations between radiographic findings and functional or pain outcomes. I think subtle issues like progressive subsidence, osteolysis or impingement may not immediately present as clinical failure, but could explain persistent symptoms or delayed recovery trajectory. So I think including that data would probably help us better understand why some patients don't progress as expected.
- [24:42]
A
Perfect. All right, thanks for elaborating on that, Tim. Little bit more involved question, but I love the tables you put in the different, you know, I'm kind of a picture worth a thousand words kind of guy. Some of your tables are even more complex, but it includes a lot of very important data. So table five to me is really well presented, beautifully presented, and it details the comparison of demographics preoperative promise scores of patients in the bottom quintile at three months. In the results, you emphasize that the patients in the bottom quintile for all three promise score measures at three months had corresponding low pre op scores. You suggest that identifying these patients with low pre op scores that most likely will carry lower scores into their early recovery may benefit from proactive interventions such as pt. And we touched on that earlier. I'm sure that you addressed this in the manuscript, but could you clarify that if such early intervention allowed these patients with low pre op scores and low scores at 3 months to reach 1 year outcomes similar to the rest of the cohort, or should we just consider not performing total ankles on patients with low pre op promise scores?
- [25:53]
D
That's a great question and thanks for taking the time to look into that table because it's pretty busy. The short answer is I think you can do total ankles on these patients who start out low, but they're going to climb that mountain and hit the same peak on the mountain as the high performers, if you will. It's just the valley is a lot longer to climb out of. So if you identify these low promise score people, your recovery roadmap is going to be slower. You have a bigger hole to climb out of, you got a longer mountain to climb up. It's still valuable. But that's sort of setting expectation management for these cohort, which is like, yeah, you're starting pretty bad, so just set expectations, keep on it, don't worry about it. You got to keep on working hard. I think that physical therapy for that group could help because I think they're probably chronically deconditioned anyway, and that's what got them that low promise score. But I think it can be done on patients who start even lower.
- [26:57]
A
Great answer. Yeah, thanks. I think that's an important part of the paper. So thanks for taking the time to give more detail. David, I have been leaning on you a little bit for more broad questions that deviate a little bit from the paper, but still can be applied. I'll do it one more time. I promise it'll be the last time. As the current AOFAS President and former FAI Editor in Chief, what actions, if any, do the AOFAS leadership and membership need to take to ensure the continued growth of Foot and Ankle International? And feel free to answer in general terms, one that may be applied to other foot and ankle societies in their respective journals.
- [27:35]
C
Well, great question. The bottom line is, I can tell you the FAI is basically owned by aofas. However, it's run essentially completely independently. So there's a separate managerial board that makes the business decisions for the journal. The editorial board for the FAI is Charlie's deal, and they control the actual content of the paper. But from a business perspective, decisions on money and things such as that, that's done by the managerial board. Now, what can we do as a fas? Well, the important thing we need to do is we need to create good content. And we're doing that. So by having an outstanding annual meeting and winter meeting every year, we give an opportunity for researchers to showcase their papers at our meetings and therefore encourage them to be able to publish their papers in fai. And then also as Foot and Ankle Society, with our, basically our foundation, where we have our fundraising, we can fund research. And this last year, again, we funded over $250,000 in foot and ankle research projects and all those, we do have a first right of refusal with regard to publication, with regard to FAI or fao. So that's what we're doing. Bottom line is, as AOFAS members and as the board, we need to just keep producing advances in orthopedic foot and ankle surgery so we can publish about it.
- [28:53]
A
Great. Thanks for taking the time. That's a great insight too. Well, we'll wrap up here. Tim, excellent work. Again, as our podcast comes to its conclusion, as senior author for this manuscript, is there anything else you would like to share with the listeners?
- [29:09]
D
Yeah, thanks for the opportunity to talk. First of all, the thing I want to share about the listeners is not about paper, though. I think it's about the process. I sort of, tongue in cheek, tell people that I'm in the top four foot and ankle surgeons here at Cedars because there's only four. So I know I'm in that window. And you're very generous to call me the senior author. But I have to say, and this is sort of speaking to the mid career people or early researchers. In my whole experience in two decades, Dave Thorderson has never put himself as lead author. He's always celebrated other people, he's always tried to promote other people. He's nodding his head because he doesn't want it. He's too humble to admit it. But I really just want to reach out and say, hey, if you want to be a researcher, you want to inspire people, make them the stars of the show, your ship will rise. Everyone knows who the senior author is and it's really sort of a testimonial to humility and excellence that you don't have to toot your own horn. And I really tip my cap to Dave.
- [30:10]
A
Well, that is a great message and good one to conclude with. So I would like to thank Dr. Spiscoia, Dalton and Thordason for sharing their insights on their and their co investors. Foot and Ankle Publication Foot and Ankle International Publication Trajectory of Recovery Following Total Ankle Arthroplasty Using Patient Reported Outcome Measurement Information System or promis. And I would like to thank everyone for participating this month's FAI podcast. This is Mark Easley and I look forward to next month's podcast.