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  • 5th Metatarsal Fractures - Jones Fractures
  • Lecture Transcript
  • Dr. Schoenhaus wanted me to talk about Jones fractures. And I will present this to you. I‘ve got some experience with this particular injury. Again, my disclosures, we’re going to first define this, what is this. The medical literature, the orthopedic literature has gone a little sloppy in years distinguishing between a proximal fifth metatarsal fracture and a true Jones type fracture. We want to look at the vascular supply. We know that’s the issue. It really is the problem of this particular type of injury. We’re going to review treatment outcomes and look at the type of fixation. Well, you know this, Robert Jones, he was an English orthopedic surgeon. He was attending a military dance. They had a big dance in this tent and he twisted his foot and eventually wrote about it. The title was “Fractures of the Base of the Fifth Metatarsal by Indirect Violence”. And it was six case reports including himself. And this is the definition. This is what we look at. It’s a transverse or very slightly oblique fracture. The key here is it extends into the metaphyseal-diaphyseal junction between the fourth and fifth metatarsals. Now, it can be 1.5 to 3 centimeters. To me, that’s not as important as the fact that you can see the fracture extend into that articular surface. And this is a Jones fracture. The literature has divided the fifth metatarsal into three zones, among many of that have referred to this. And if you take a look at the purple-shaded area, that’s where the Jones fracture occurs. That red shadow area is proximal to that. That’s where avulsion fractures usually occur. And then, the normal color to the shaft distal to the purple is where stress fractures can occur. They can be transverse. Other types of fractures can occur but it’s not of Jones fracture if it’s up in that area. So, on the right Jones fracture, this is what it looks like. On the left, there’s no articulation there so this is just a proximal fifth metatarsal fracture. Although our treatment may be identical for your boards, I tell you the difference between on the mechanism of injury or Jones himself said he had body pressure on his inverted foot with the raised heel. And this is the best picture I could come up with to show you what the foot look like. And other doctors now had become more sophisticated and said, well, it’s a direct vertical ground force with failure of the foot to invert. It’s certainly is, the foot is fixed in inversion and then adduction of the foot occurs. And then, we have the anatomy that comes into play. For years, everyone thought it was the pull of the peroneus brevis tendon but then it was investigated. And the lateral band of the plantar fascia attaches to the plantar tip of the base of the metatarsal, and that’s felt that’s what really causes avulsion fractures and even the Jones fracture which is certainly a form of an avulsion fracture. And then, when that pulls and the foot is in that position and the lateral band of the fascia pulls, we get the break and the bone failure or the bone in this particular manner. And you can see, this fracture, even though slightly oblique, it is going into the articulation between the fourth and fifth metatarsals. By the way, I wanted to show you this. This is something that can result in the Jones fracture. This is metatarsus adductus foot and all the body weight is on the plantar lateral aspect, fourth and fifth metatarsals. These people get stress fractures all the time. Usually on the fifth, it’s midshaft but I’ve seen them in the area, in the location where a Jones fracture would occur. So here, it’s not an acute trauma so much but a chronic repetitive trauma that can result in this. So, just keep that in the back of your mind. Well, here’s the problem with a fracture in that area and this is why we’re even talking about this today, is the blood supply is not good right at that juncture. Now, this is called the watershed area. And what the heck is a watershed? I’m from Detroit, we know about transmissions and stuff. So, I googled this thing and apparently, it’s a term from geography. And it refers to like a prominent portion of ground where water at the top may flow off on either direction but the top may actually be somewhat dry because the water is gone. And that’s what I have circled for you. The metaphyseal arteries will end roughly at that junction. There are multiple metaphyseal arteries. There’s just a few branches from the nutrient artery so we have that little zone of decreased vascularity. And when we break through there, it takes longer to heal. Outcomes are not as good.

    [05:04]So, treatment. Bear with me a little bit here because I’m trying to demonstrate something to you. So, look at the activity level of the patient. Look at the age of the patient or occupation or their functional demands, you know, is this somebody who needs to get back on their foot quickly? Is this an athlete under contract who has to return to competitions quickly as possible? Or a factory worker who needs to get back to work? Or is this somebody who is retired and maybe taken life easy? The other thing, the literature shows, we’re looking at 68 weeks in theoretically a nonweight-bearing cast, maybe another 68 weeks in a weight-bearing cast. So, these take a long time to heal. So, if we look at the study by Clapper, this is almost a classic study. He had a group of patients that he followed. And there was no medullary sclerosis and by that, no evidence that the patients’ fractures were going on to nonunion. And he monitored them, 72% healed at 21 weeks. Well, that’s a long time. But he had 28% failures who eventually had the surgery to fix this. So, I think this is a real good article to keep in mind when you’re evaluating your patients. I don’t know how to pronounce this gentleman’s name. Goefferson, I believe, 66 Jones fractures, 27 acute, 39 chronic. One-quarter of the cast patients had surgery because of nonunion or refracture. And refracture is a problem with this Jones fracture. So, we’re picking up a pattern now. Fernandez, 50% of his patients treated in the cast healed at 12 weeks. Patients treated with bones bruise healed at 9.5 weeks. And I question that 12 weeks. I’d personally like to see those records. I put this in just to perk you up a little bit. Take a look at this, Goefferson again. After 17 years, the range 11 years to 26 years, 33 fractures have healed. Seven cases have delayed healing. So in my case, I’m in trouble because I’m not going to be around in the 17 years so I’d have to pass this on to you guys to follow. This is showing you though that if your patient is healthy and young, you’re starting to lean towards surgical stabilization and repair. Refracture, I told you that’s a problem. One-third of all the Jones fractures treated with immobilization in Quill study had refractured. And in Porter study, no incidence of refracture in athletes treated with screw fixation. So, you see where I’m kind of going with this for you. Dameron, again, another classic study, 25% nonunion with just immobilization. Cast versus surgery, another one, 18 patients with cast, he had eight failures, five nonunions, one delayed union, two refractures that took 14.5 weeks to heal. He’s grouped with 4.5-millimeter malleolar screws, one failure in nonunion, 7.5 weeks to nonunion, 8 weeks returned to sports. So, I think of all things are equal. We’re going to repair these fractures. Now, how do we do that? There are many ways and K-wires, tension band wire, neutralization plates, hook plates, bicortical bone screws, intramedullary bones screws. Right now, the intramedullary screws seemed to be the most popular type of fixation both in our specialty and in orthopedics. And they have a lot of advantages and they’re percutaneous. You only need to make about a centimeter incision. We don’t disrupt the periosteum. I do think this results in faster healing, no, reduced surgery time. If you’re skilled, you know, yes, it is. Within minutes, you can have the screw in place. Sometimes, for new residents, it takes a while for them to run the K-wire up there for cannulated screw. There’s minimal postoperative pain because you only have a little incision. Do you achieve interfragmentary compression? Well, some think you do if you use the right size screw with this. And I’ll show you what I’m talking about the study by Kelly, a cadaver study. He compared 5.0 with 6.5 screws and determined that the 6.5 millimeter screw had greater pullout strength because of the bigger thread pattern. This is [indecipherable] [09:38] study. And if you take a look at this, there’s two things that catch my attention. One is the very prominent head on the screw. And the other is the thread pattern biting into the inter surface of the cortex. Now, you know, you don’t want this. I’ll show you what you want in a minute but this is cutting it close. And so you see what happened in this study.

    [10:00] As he put in a screw that was too large, he sustained a fracture, medial wall blowout with that. And I think he did use a 7-millimeter screw here. So, we know that’s not the right size to use. And so, here’s the other thing. We just talked about the diameter. Now, look at the length. If there’s lateral bowing, you have to stop the screw before the fifth metatarsal starts to bend or bow because if you hit that distal medial surface, it’s going to displace the metatarsal. And you see here, you see the fracture before. Notice, it was reduced but as the screw went in, the screw displaced it. Now, yes, this eventually healed but, you know, you’d like to put in the screw a little bit shorter so you don’t have to deal with an issue like that. So, this is the study by Scott, actually Chris Hyre, 20 cadaver limbs. He did measurements inside diameter or the fifth metatarsal at the narrowest point and the average height was 6.475 millimeters, the width 4.6 millimeters. You have to measure this yourself on each patient because it varies. Conclusion was you shouldn’t use a screw smaller than a 4.5-millimeter screw. And here’s how we do it. If you take a look at this x-ray, we measure the inside diameter of the cortex and we looked at the configuration of the metatarsal. Is it a straight metatarsal? Is it lateral bowing? Is there any deviation? That helps us determine the length that we want to insert as well. So, now with this, you’ve got information to go into the case with. If you use a screw that’s too loose, you can have displacement. Too big, you can break through the cortex like I’ve shown you. You need a screw that’s just going to snug up against the inner surface of the cortical walls. And the theory is by doing that, you achieve some degree of interfragmentary compression, usually 4.5, 5, or 6-millimeter diameter screws. And this is how we do it for our residents. We don’t have them load the wire on to the handle. First, we will bring in C-arm like this. I want them to get a feel for where they’re at before we start with the handle and start drilling multiple holes in the metatarsal base. Many times, I’ll take a skin marker and I’ll mark the outline. And what I see, the tendency is for the resident to lift his hand so that he’s going to go into the base and he's going to come out the plantar surface. Sometimes, it has to do with the position he’s in. He just can’t visualize this well because C-arm is in the way and everything but that’s where we use the other people in the room to help guide him in. So, now once you have that in, usually you can just advance this K-wire for cannulated screw or for solid screw, whatever you’re doing. But if you come up against the cortex, if you gun it, you know, you can drive it right through the cortical wall. So many times, we’ll switch over to this and we’ll just tap it in and the wire will follow the medullary canal. And then we’ll tap or we’ll drill. In here, we have to tap the area and we’re inserting a shorter bone screw. This is the solid bone screw. And notice, I’m ending short of the lateral band. And this is a 5.5-millimeter Jones screw. This has worked beautifully. And if you take a look at those distal threads, they’re snugged up against the inner cortical walls, strong, stable and this is ideal if we can do this. And you can even use a cannulated screw but sometimes, they’ll break but that is usually much easier for people to insert. Just use a larger screw that you can safely use in that metatarsal. Real fast, I got a few minutes left, how do we repair them? This is very simple technique, the nonunions. I tend to use bone graft although there’s other products you can use and I like autogenous bone graft a little bit better. So here, I’m using a trephine and I’m trephining a hole right through the nonunion site. And I can either go to the distal tibial metaphysis, that’s beautiful, rich cancellous bone. Or I can go into the calcaneus, same thing, it’s just a perfect bone for something like this. And we’ll get a nice plug like this. And I’ll usually leave the periosteum intact. We insert it, tamp it in. In here, it’s a simple neutralization plate. A little bit tough to get an interfragmentary screw in the fifth metatarsal that is a transverse fracture because you just don’t have much bone to bite on to. It can be done but sometimes, it’s just the effort is not worth the result. And so, it’s a simple technique to fix this.

    [15:01] If I need adjunct fixation, I can use a metatarsal cage like I have here. And I might use it if it’s a painful nonunion that I’m repairing and somebody who has some degree of osteoporosis, somebody who is heavy, somebody I know that cannot stay off of it, I’ll do something like this. We can even double plate if we need to. Usually, a quarter-tubular plate or we might use a straight plate or even another quarter-tubular plate. See, these are little like backup tricks. So, you can use them. So whatever fixation you use as long as it's applied appropriately and you have stable construction outcomes. They should be very good with that. So, consider the requirements of your patient. This lady wouldn’t necessarily need surgery, you know, she is not doing too much. But these guys absolutely without a doubt I wouldn’t hesitate to fix the Jones fracture on them. If you use a beam, use the largest screw that the canal can accept. And, you know, you’re essentially beaming the fifth metatarsal and actually give you a good experience for when you start beaming for the Charcot reconstructions as well. Questions about anything? I'm finishing about 11 minutes early. I hope you enjoy the talks. Thank you very much for having me.