• Lecturehall2nd MPJ Pathology and Treatment
  • Lecture Transcript
  • Host: You know, at this late stage in the meeting we don't have to introduce our [Indiscernible] [0:00:05] of the profession, but Bruce Werber is certainly a continued member of our educational community, both here and all over the US. So, Bruce, you're going to talk about second MPJ pathology and pathophysiology, right?

    Bruce Werber: Absolutely. All right. Well, a small group; feel free to ask any questions as we move along. Second digits probably are the most difficult challenge. I'll take a rearfoot case any day, midfoot, happy; bunions, happy, but second toes, I'm sure you all have the same aggravation. It's difficult to get a perfect result every time, but I think as we learn and we progress here I will add some new techniques to plan a plate repair that I'm going to show you today. This, I think is an advance towards solving the dilemma of the crossover toe, unstable second, chronic metatarsalgia, synovitis, etc. So, I'm just going to go through a little history and some diagnostic tools that we need.

    Certainly, we want to know who the patient is, what are their goals, where are they coming from, are they runner, are they dancer, are they wearing high heels all the time and then, of course, the biomechanical issues, what's the medial column, is there decreased stiffness in the medial column, so they're getting overloading of the second metatarsophalangeal joint, has there been rupture of the plantar plate, is there a positive Thompson test, so we're going to go through some of this. I'm going to show you some of these images and we will go through and then, of course, getting the appropriate imaging to rule out other pathology around the metatarsophalangeal joint that could be contributing to deviation of the digit and instability at the joint itself.

    Most commonly, we see rupture of the lateral collateral ligaments and that's when the toe starts to drift over the great toe and we get a multiplanar deformity. Certainly a differential diagnosis needs to include neuroma, stress fracture, flexor tendonitis, synovial cyst, chronic bursitis with significantly enlarged bursa, avascular necrosis of the second metatarsal and, of course, what we're going to really focus on today is plantar plate rupture.

    So, really, we call it Lachman test, but really, it's Thompson and Hamilton that described the vertical instability and the, you know, as we go through the test, to raise up the proximal phalanx and essentially sublux it off of the metatarsal head and this is an important evaluation that you need to document. They described several stages of this testing of vertical displacement where there is some displacement, but there is very little discomfort and gradually as we move through the three stages, we have increasing levels of deformity and pain. We also, you know, and then Mulder's sign, the compression. Typically if it is localized to the metatarsophalangeal joint, you're not going to get much discomfort with compression from medial to lateral, negative Mulder's, so we want to include all of this. You want to obviously make sure you're documenting all of this.

    We look at the radiographs. Just to repeat, we want to look at the subluxation at the second MPJ, is it drifting medial, is it drifting lateral, is there loss of the joint space, what exactly is happening and, of course, are there any other osseous deformities that we may note on radiograph. Certainly here we can see unstable, subluxed on the left and then on the right dislocated metatarsophalangeal joint and you're all aware of this and I'm going to pretty much run through this diagnostic part and spend a little more time on how we repair it.

    I find ultrasound is a tremendous tool in the office for evaluating forefoot deformity. I think it is really an essential tool we all should be experienced with and learn how to use. You can absolutely assess the flexor tendon, the plantar plate, the integrity of the metatarsophalangeal joint under ultrasound as well as rule in or rule out any soft tissue lesions. So, here is a normal ultrasound of the second MPJ and we can see the flexor tendon, plantar plate, metatarsal head, phalanx and then we can see the rupture right in here of the plantar plate and I'm sorry these don't'it's hard to get these ultrasound images really to translate well to photographs, but you can see the rupture here. It's pretty clear when you're doing it live, that you can see the rupture of the plantar plate on the inferior aspect of the proximal phalanx and it's good. If you don't know ultrasound, help yourself to an ultrasound course. It's a low learning curve and, again, very, very beneficial to your practice and your diagnostic skill set.

    So, here we use a small scope, a 2.8 scope and visualize inside of the joint and we can see and typically with these deformities, quite a bit of synovitis within the second MPJ, we can see some chondral tearing down and it is hard to visualize the tear of the plantar plate here, but this is typically what you would see if you took a scope, if you want to try this before you get fancy and just do this through a small portal, you can do an open arthrotomy and bring in a scope and just have inflow through an 18-gauge needle and you can get a good visualization of the joints and see the pathology to understand what you need to do to fix it.

    So, we can also have MRI and here are some fairly clear images of plantar plate rupture. You can see the metatarsal obviously and we can see the rupture of the plantar plate right in here. Another view. And, so, MRI is great. You need to be able to read this yourself or have a good musculoskeletal radiologist who is willing to take the time and evaluate this area and get good images and we can see it here in the axial fat-suppressed image very clearly. So, a good diagnostic tool and the cost is coming down so that should not be a factor in deciding to use MRI for making this diagnosis. And we can see them very clearly here.

    So, Weil did some diagnostic studies. They did a study and developed some review of the literature as well as developing procedure and then following it up and they looked at MRIs, how specific are they or how sensitive are they? And so they took about 40 some odd patients and they went through over the course of a year and they had the patients undergo MRI and then they had surgical intervention and what they found was 39 cases were read as tear and all 39 were confirmed with a tear. Six cases were read with no tear, in that four of the six were definitively shown not to have a tear in the plantar plate and then two of the six in fact did have tears, so it shows quite a bit of high sensitively, fairly good specificity. It's positive predictive value was 100% and its negative predictive value was 67%. So, it gives MRI very positive, worthwhile time and cost factor is tremendous to justify ordering MRI for this diagnosis. So, it is good for ruling in, not so good for ruling out, may get some false positives, but the number is quite low.

    So, what causes this? What is the etiology? Well, like I started to say in the beginning, we have a biomechanical etiology of the decreased stability of the medial column. First ray, if it has decreased stiffness, we have mobility at the first metatarsal cuneiform articulation because of the peroneus longus not functioning correctly. We need to look at that rearfoot pathology to understand where the instability is coming to the forefoot. Now, this can be accelerated, exacerbated by shoe gear, certainly wearing high heels with very thin soles can add quite a bit of shearing to the forefoot and if the medial column is unstable they are rotating on the second and third metatarsal heads.

    So, that's the biomechanical component. We certainly have the rheumatologic components of gout, seronegative-seropositive arthritides, ligamentous laxity, poor collagen formation and, of course, there is trauma.

    Corrective options, conservative. We can start, if we have it in the early stages, maybe just a partial rupture, we can look at immobilizing the joint, stabilizing the medial column. I do not recommend injecting into the joint, but consider, if you really want to use, a steroid, injecting more proximally. You need to deal with the biomechanical issues, changing the shoe gear to allow this to heal. Sometimes if they come in and it is acute, but it is only a partial rupture, there is not a lot of deformity to the toe itself, then I'll put them in a Darco OrthoWedge shoe, so we're offloading the forefoot, all the weight is on the heal, allowing that forefoot and the capsular tissue to heal. I may put them into an orthotic with a kinetic wedge if they have functional hallux limitus. Look at loading or putting more of a lateral wedge if they have a forefoot valgus, kind of trying to imitate Evans by kind of lengthening the lateral column and putting more biomechanical support there to give an advantage to the peroneus longus and maybe that will allow the medial column to stabilize.

    I need to address the equinus issue. We can consider using cold laser. Again, these are in patients where it is acute, early onset. There has not been a total rupture of the plantar plate and there is not a rigid deformity at the PIPJ, just still in it's early stages. We can use these alternatives. As we move on, maybe they have more instability, but still not a rigid deformity at the PIP joint. I have used the combination of extracorporeal shock wave therapy to create a inflammatory response in the area and then inject in and around the metatarsophalangeal joint with amniotic membrane and fluid and for 10 patients done over the past nine months, all 10 have resolved and we've actually seen the plantar plate partial tear be eliminated. Now, this is following the ESWT and the injection of the AmnioMatrix. I needed to splint. I put them in a OrthoWedge shoe to offload the forefoot and I kept them in offloaded position for two weeks and then put them in running shoes with appropriate orthotic control and so far we've had tremendous success. Again, these were partial tears and not total tears and no rigid deformity or crossover.

    And here we are. I have a little'hopefully it will work. Can you click on'? No? It's not working. Movie is not going. Well, this was, I was using'so for a more significant deformity here, I would be arthroscopically visualizing the MP joint, that's a Topaz wand radiofrequency Coblation to resolve the synovitis and actually in some cases, just by using this, clearing up the synovitis, doing a Weil osteotomy and doing an arthrodesis with a flexor transfer, we're able to get quite good success in stabilizing, but there was always a risk of a floating toe after its lack of toe purchase and I'm sorry the video doesn't work cause it really shows the plantar plate tear with synovitis around it, but we'll have to move on.

    So, that's one alternative, is to use Topaz while osteotomy, reestablish the parabola, stabilize the medial column and do a traditional arthrodesis at the PIPJ with a flexor transfer. That seems to be a lot. There is not a lot of'at least for me it's not always 100% successful and it took a lot of time to get a floating toe, so what else can we do? Well, why can't we just go and repair the plantar plate? So, I started just taking some fiber wire and suturing through the medial and lateral portions of the plantar plate and plantar capsule actually is what I started with and bringing it up and having a drill holed through the proximal phalanx and I was having pretty good success, but then I was talking to Dr. Weil and he had an advance over this and he would drill two holes through the proximal phalanx and then suture and bring the suture up through both holes and tie it over the proximal phalanx and this certainly has given a significant improvement in how it can control the position of the second toe. It has reduced the incidence of floating toe and I'm not doing as many arthrodesis and I'm not doing the flexor transfer when I do this. I seem to be getting great stability.

    So, now we move on and this was described by Weil in Techniques in Foot & Ankle Surgery in March 2011, so now, kind of moved on to a modification of that and Arthrex is coming out with a little device that I think will make this procedure much easier. Doing a Weil osteotomy, you can take a McGlamry elevator. I don't typically do that. I just bring the head back, distract it quite a bit to give myself as much room in the joint space and you're going to be able to take this little grabber'has anybody ever used the'if you've used the OPUS anchors. There is a Mini Magnum. It has a little suture. It's like a mattress suture as well. Well, Arthrex has one called the Scorpion and they've miniaturized it to allow us to get into the metatarsophalangeal joint and this creates a little mattress stitch, which you put on either side of the plantar plate, you're grabbing that plantar capsule and the plantar plate. You could free hand it. You could use the OPUS Mini Magnum, but it's a little large. You need more dissection to get it in there. I typically use just some fiber wire. It works out fairly well for me, but now that we have the Scorpion, this makes it much easier. So, you just take the Scorpion, you put a stitch through it, you bring the stitches up through the proximal phalanx and you couldn't see the holes, but I kind of tried to emphasized in there, bring it up through the proximal phalanx and you just sew it down and you get a very stable construct, very stable repair at the metatarsophalangeal joint and a nice straight toe with toe purchase and here it is. It is knotted and'then you fixate your metatarsal head back in position. A standard way of approaching a Weil osteotomy and putting in a'typically it's a 12-mm long screw and I use a 2.0 cannulated. I like this brace that Weil's group has developed. It allows the toe to be splinted and I have the patient exercising, using the flexor tendon as much as possible. I send them to therapy. I have a couple of therapists I use and they know to focus on strengthening the flexor tendon and rehabilitating. I have them walk around in this for about four to six weeks. They use it inside their shoe with an orthotic after about two to three weeks. And this is Weil's study. His group, they presented it at the summer meeting and they showed quite a bit of success with this procedure as you can see here. Very, very successful, minimal complications and absolutely great outcome and I'm running out of time. So, this is a great procedure. There is a bit of a learning curve, but not much, just you can practice in the cadaver lab and you get really spectacular outcome. Many, many authors have described this over the time, but this seems to be the best procedure to date in repairing the second metatarsophalangeal joint and in giving us a fairly reliable outcome and I'll finish up.