• LecturehallForefoot Amputations
  • Lecture Transcript
  • TAPE STARTS- [0.00]

    Male Speaker: I can speak about Forefoot Amputations which by far are the most common of all that we do, the most common amputation done in diabetic patients, as well as non-diabetic patients, is toe amputations. So, let’s welcome back to the podium Dr. Suhad Hadi, local girl now.

    Suhad Hadi: So I’m going that just walks through this lecture now that I have been granted more time, but it’s a great talk, Dr. Woo [phonetic], and I think I’ve just learned that I’m a polygamist that indeed we marry our patients. So I’m going to talk about forefoot amputations. Unfortunately, I cut out the part about midfoot amputations that I’ve known, but forefoot amputations, again most common amputations that we probably deal with our patients. My goal with this talk is to help understand the impact of the amputations, which I think we have gathered that from the previous talk and discuss the risk factors for amputations. And I think most importantly how we’re interpreting the amputation outcomes that we’re seeing in the studies that we are seeing now and how they should impact how you perceive with an amputation and amputation level selection for your patients, and then the long-term management of amputations, what we have today in terms of sustaining amputation at particular levels when we perform them. Right now, we know that amputations account for half of over 80,000 diabetes-related amputations per year. We have over 60% of non-traumatic lower-limb amputations, over 60,000 non-traumatic lower-limb amputations and there is about an average of 18 months from initial amputation to any secondary or subsequent amputation in patients. 15% probably more today of amputees are diagnostic diabetes at the time of their amputation and 25% to 30% of foot amputations actually will progress to below-knee amputation or more major amputation, regardless of initial amputation level. And again, average of 18-month interval between first and second amputation. The nice thing that we are seeing now with multidisciplinary teams and more comprehensive foot care and amputee care is that about 70% of below-knee amputations regained functional mobility and I think that we’re going to see a larger trend of salvaging foot-level amputations and giving them a better longevity in regards to how we are able to shoe them and work with prosthesis to keep them functional and again community amputee layers within society. The risk factors, we’ve gone through them pretty much throughout the entire session today, but peripheral neuropathy, altered mechanics, peripheral vascular disease, history of an ulceration and then history of amputation. The biggest indications that push us towards amputation in our patients are in infection, ischemia need to revise to a more functional level if an initial amputation was performed to eradicate infection and then the patients taken back, and then reduction of any deformity that may be resulting in pressure or infection in these patients. I think regardless of amputation level, maybe excluding partial toe amputations, you’re going to find that you’re going to get complications in regards to altered mechanics, instability of the foot and subsequent deformity which can result in new areas of pressure that need to be addressed post-amputation, again to give a greater survival to our amputee patients. In regards to toe amputations, they’re generally well-tolerated, especially when their partial toe amputations are distal amputations. They have little effect on walking speed and contralateral limb weight distribution. They may have a slight compromise to running or jumping activities. And then the risk for secondary deformities of adjacent toes is probably one of the largest factors that we are going to be dealing with, mainly because you lose a digital buttress. So if you have to take a toe back at the base level, at the metatarsophalangeal joint level, you’re creating a large defect between adjacent toes and this can subsequently result in either transverse, sagittal, or multiplanar deformity of those to adjacent toes, which could cause more problems down the road in regards to transfer lesions. Griffin [phonetic] and his group did a study focusing on risk factors for progression to future limb loss after toe amputation. I don’t think they were trying to disregard the success of toe amputations. What they did was a retrospective review of 63 patients, 43 of them which had diabetes and 31 of them which had to undergo lower extremity revascularization, 35 went onto further amputations. So they had an over 50% rate of re-amputations and patients who had toe amputation. What they concluded is that toe amputation itself is a significant predictor of future limb loss. But interestingly enough, what they’ve found was that the diabetic patients were the less likely population to have to undergo subsequent amputation. It was actually the non-diabetic population.


    And they attributed that to, as what’s mentioned earlier by Dr. Woo, that we have more intensive multidisciplinary foot care teams now taking care of these patients and I think we are learning to recognize problems earlier in this population. So I think that was an interesting finding in their study, the toe amps. So when we talk about techniques, classic fish-mouth incision at the level of resection creating an apex, both medially and laterally to reduce the risk of getting dog ears at your flaps and re-approximating them. If you have a lot of dorsoplantar tissue loss in the process of doing the toe amputation, you can rotate that incision and create a medial and lateral flap. If you have to take at the base, again, this is when you are risking losing that buttress effect of the digital stump. I personally don’t do toe amputations at the metatarsophalangeal joint level only. I don’t like leaving that space defect. I do find that you are going to have problems with the adjacent toe. So if I have to take at the metatarsophalangeal joint level, I will talk to the patient about converting that to a partial ray amputation. In my opinion, I’m able to re-approximate the area better if I take a portion of metatarsal stump and bring the incision sites closer together and reducing the space, the deficit between the two adjacent toes as well. Another important factor to remember, too, is to leave -- I can’t see my thing. If you’re able to leave -- this is not working for me. If you’re able to leave tissue on the adjacent side of the toes medially and laterally, that helps you close the space in the web that you create. If you’re too far off into the web space in planning your incision when you’re taking right at the web space, you’re going to have a harder time closing distally. So if that skin is viable, be cognizant in your incision planning and try to leave a medial and lateral portion at the base of the toe, so that helps facilitate your closure long-term so you don’t have to leave an open wound if you don’t have to. Hallux and partial first ray amputations, this is a long-lived slide from my days of residency. I remember when I was attending an UTM [phonetic], the residence came in and we are just freaked out that this patient had this bottle cap on the bottom of his foot. In the mean time, he was denying alcohol and he was denying walking barefoot. So we’re going to talk a little bit about hallux amputations and partial first ray amputation. These are amputation level I think that have been described to be prone to most complication, the lost of that medial column stability, the lost of the first ray or compromised to the first ray. I personally think that we’ve underestimated the success that we can have with partial first ray amputations and hallux amputations. And I think that we’re going to look at couple of studies and I think if you look at how you interpret the studies and look at more the successful outcomes of these studies rather than the failures, you’ll see that this is actually a good procedure to keep in regards to amputation planning. So first of all, you want to understand the natural history when you amputate a hallux or the partial first ray and compromise, you are going to have progressive deformity. I tell every patient who undergoes a hallux amputation or partial first ray, if they don’t already have digital contractors overtime, I let them know that they will develop that because the long extensors are going to take over and work to stabilize the foot because you are losing the stability medially and that this could be a problem in terms of allowing the plantar fat pad to advance internally and then you lose that plantar support that you have and then you can have pressure lesions. But I think we become more effective in shoe gear modifications and sole modifications, amp stump fillers and bracing techniques, which I think are underutilized right now, too. And we will talk about that in a little bit. So with partial first ray amputations, Dr. Labri [phonetic] and his group did a study where they’ve found that there was an increase in plantar pressures once great toe was amputated, that pressures were increased under the lesser metatarsals in the toes, not so much in the heel area, which is an interesting finding. Porkoskhy [phonetic] and Ruckus [phonetic] did a systematic review where they reviewed five studies and gathered information on 435 patients who underwent a partial first ray amputation. Their goal was to try to determine the actual re-amputation rate falling any form of partial first ray amputation. So, what they’ve found was that there was 20% re-amputation rate in patients who underwent a partial first ray amputation when they systematically reviewed these studies and again 435 patients. What they concluded was that one out of five patients undergone a partial first ray amputation are required a more proximal amputation. So that caused them to question the durability, functionality and predictability of partial first ray amputation in regards to a foot-sparing procedure.


    So I take this study with great result. I think it was a great review. But when you look at midfoot amputations studies, you also find that these studies show that there is about 30% chance of more proximal amputation or major amputation such as the below-knee amputation. So for me, at 20% reamputation rate, if I’m doing a partial first ray amputation on five people and four of them have a successful outcome and I’m able to sustain a functional foot and allow them to continue to function in society, I think that’s success. So to me, one out of every five is not a bad outcome. We’d love to all have 100% success rate. But I don’t think that it’s as negative as we’ve come to interpret the results. At here, we find that Kuna [phonetic] and his group did a study where they did a retrospective review of recurring ulcerations after partial first ray amputations. They had 20 patients and what they did was did percutaneous TAL procedures prophylactically in 12 of those patients. Eight of the 12 patients who received the TAL had no recurring ulcerations or complications. Four of the patients had to have further debridement or progress to transmetatarsal amputation. Though they had patients who had to have further debridement, what they’ve found was that the 8 without the TAL all actually developed further ulceration and/or amputation. So this also lets us kind of really consider what adjunctive surgical treatments we heard earlier about potential tendon transfers, to rebalance the foot, to reduce any subsequent deformity or complication that may arise. So I think it’s important for us to also recognize things that we can do prophylactically surgically while we have these patients on the table that will help also sustain their amputations long-term. Another study by Porkoskhy, where he also found that 42% re-amputation rate within about 25 and about two-year follow-up in these patients, and again concluded that the partial first ray level amputation is neither reliable nor durable. Again, I take that with a grain of salt and I still think it’s a good procedure and we’re going to talk a little bit later at the end of the talk about why, because I think we have so much more at our disposal in regards to stabilizing these feet post-partial first ray or hallux amputation. Lesser ray amputations are more commonly tolerated in the central and lateral rays. It’s important to keep a good portion of the metatarsal so that you sustain the midfoot integrity and structure of the foot. And you do have the risk of transfer lesions with this as well, especially when you take the lesser rays and make metatarsal head that’s adjacent to that more prominent, and you risk progressive digital deformities with this as well. Same as with the toe amputations, risk factors are ulceration infection, Gangrene, a failed toe amputation that has to be taken back more proximal, chronic ulceration, or tissue loss, and again trauma pain or malignancy. There are lots of outcome studies that have been done on partial ray amputations dating back from 1984 to ‘99 with varying successful outcomes anywhere from 20% up to 30%. Rezalman [phonetic] and his group in 1999 did a study that was not published but have 60% success rate with partial ray procedures. So I think it varies, I think foot type comes in to play of how you are monitoring these patients long-term. I don’t know that we have one consistent study that is showing us worsening trends in regards to success with foot amputations. I think all the studies in general are showing that we are having more success sustaining amputations at the foot level. Azumi Hartless [phonetic] and Satterfield [phonetic] did a study and published in 2006 where they actually evaluated all foot level amputations, toe, ray, midfoot and major amputation levels. What they’ve found, in 277 patients who underwent a first time lower extremity amputation between 1993 and 1997, that regardless of amputation level, well, 30% of these patients have to have a subsequent amputation in one year. And again, this was regardless of level, whether it was a partial first ray, a TMA or a toe amputation. At three years, it was 40% and at five years it was 50%. So I don’t think that these studies are showing us that there is one amputation foot level that’s better than the other. I think what you have to decide is again, what’s your patient’s function. So if I have a patient who is little more elderly, they don’t ambulate much, they are not going to be very active in society, something like a partial first ray amputation is going to be successful. Why should I take him to TMA or BKA? And I know I can accommodate that in the shoes. So you have to really take patient factors into the consideration and what your success rate and what you have at your disposal in regards to shoeing these patients post procedures. So technique, similar to toe amp at the metatarsophalangeal joint level, dorsal and plantar page, again, trying to maintain some of the skin at the medium and lateral base of the toe so that you can actually bring that web space close if the integrity of the skin forged you that.


    Again you want to bevel the metatarsal resection, examine all the tissue plains and decide whether or not delayed or primary closure would be necessary. That’s more. So again, with partial ray amputations and especially first ray, you can compromise the medial column integrity versus medial arch collapse, adjacent toe, you lose the digital buttress that we talked about, you can have development of progressive digital deformities down the road and increase the plantar prominences. So this is another one. I am still always amazed as to what we’ll walk into the clinic. Just when you think you have seen it all, this is a patient who when I pulled the piece of candy office foot [phonetic] that he told us he was looking for that piece of candy and didn’t know where it went. But you know, don’t undermine what you’re going to see in your clinic. Ultimately, I think every amputation level’s success comes to how we’re managing these amputations once the amputations are done. So I think this is the key to the successful outcome of your amputation. Shoe gear and soles with appropriate modifications, advanced bracing techniques, and adjunctive surgical treatment. When we talk about shoes, shoes have become a lot more attractive for our diabetic patients. They have become more accommodative. They’re more willing to wear them. And I think this is going to add to our success with the different amputations levels. Know what you are prescribing when you are prescribing insole, and the modification, and the filler, when you prescribe a rock replacement, make sure you’re offloading the area that you want to offload, make sure you’re putting it at the correct level. If you question that, communicate with your prostheses and make sure that this is being done appropriately for the patient and you’re going to be able to sustain all the work you’ve done to get this patient heeled at the amputation level. When I do a midfoot amputation or I do a partial first ray amputation, I’m a little more aggressive in the post-management of them. I will do something like metal hybrid shoe brace or double upright, I’ll do an AFO, something that will reduce that forward propulsion moment in their gait and not allow them to put so much pressure on their forefoot and help them to roll off of it. So the nice thing about the metal hybrid shoe brace is the variable joints of the ankle, you can actually lock the motion of the ankle and give them the less of a propulsive gait or you can actually allow some of the motion into the ankle and you can dictate how much of that you permit, allows for axial loading via molded plastic [indecipherable] [17:37] and it’s less likely to give you a skin breakdown because there is less contact on the skin of the lower leg as oppose to that of an AFO. The role of the AFO again, especially in TMAs, but I find very successful also with my partial first rays, it replaces a lost lever arm, allows for offloading, helps stabilize the deformity that is now created with the amputation. And most of my experience has been with the BlueROCKER AFO. We worked with that one a lot when I was in Seattle with the amputee rehab team that was out there with Rock. And so keys to success is knowing what your patient’s vascular supply is, that’s going to have your greatest impact, like I mentioned earlier in one of my earlier talks, I think we in general have become more adept at recognizing this in our patient populations. Eradicate infection, make sure you get rid of infection. I think a lot of studies have re-amputation rates because initial amputations have been done to eradicate infection than subsequent debridement, subsequent amputation is being done and this adds to the re-amputation rates that we see. Functional capacity, make sure that you are sustaining an acceptable level of function for your patient and a reasonable expectation for both you and your patient. Shoe bracing, long-term foot care program was mentioned earlier in talks and Dr. Woo recently have these long-term foot care programs, have really come full circle in helping these patients and again patients’ expectations and function and don’t downplay the role of adjunctive surgical treatments. A couple of these studies that I mentioned earlier, the TAL study even Porkoskhy and Ruckus’ study said they could not account for how aggressive bracing was or was not done for patients and what the role of adjunctive surgical treatments could have been and how they could have been beneficial for the patients even a pan metatarsal head resection, the TAL. So don’t downplay the role of these in making your amputation successful. So again, understand the impact of amputations discussing the risk factors, interpret your amputation outcomes, be critical, try to focus more on the success. And if the success numbers are pretty high, I think it still allows for that procedure to be one that should be utilized and then long-term management of your amputations. Thank you.

    TAPE ENDS – [20:05]