Hello. My name is Jane Boswell, and I'm going to, talk today about the magnetic resonance imaging and treatment options for horses with injury to the digital part of the deep digital flex tendon. Deep digital flexor tendon injuries are a frequently diagnosed and often career lifting injury in horses.
These injuries are often associated with chronic pain and prolonged lameness. And certainly, poor foot confirmation, particularly those horses with neutral to Palmer planter angles, so long toe, low heel, foot confirmation. Those horses that are doing high impact athletic work, and also horses with concurrent navicular bone pathology, are associated with.
An increased risk of developing DDFT as higher peak forces are reached in the tendon, which thereby increases the risk of development of tendinopathy. Certainly, the rapid expansion of, diagnostic MRI available now across the globe to equine, sports medicine has massively increased our awareness of this condition. Previously, before the widespread use of MRI.
It, this condition was believed to occur, but the difficulties of, confirming diagnosis at that time, which largely depended upon ultrasound, meant that it was, not frequently diagnosed. But the low field MRI system, particularly the hallmark standing system that is now available. In many countries across the world, providing MRI, at relatively cheaply to the owner, and without the requirement for general anaesthetic, means that we are, much more aware of this condition, and it is much more frequently diagnosed.
Magnetic resonance imaging is, widely used. And, and, and the, beauty of MRI is that we can get exquisite three dimensional, images of the, of the horse's foot, and, or, or the, the, part of the extremity that is, is being scanned. And, and this allows us to, to look at, we can select the plane that we look at, the, area of interest in, and therefore, build up good information, about, about the area that, that we're looking at.
So, here, we've got some examples. Of, different, planes, we can see here that we've got a frontal plane scan, through the, the, the, the foot. And, and this, frontal plane scan is, is just slicing through part of the, the digital flexor tendon with the arrows here pointing towards the lesion, there.
Here, we've got a, a sagittal scan, and, and, and, the encircled area is showing, pathology in, in the navicular bone. Whereas this, image here is looking at a transverse scan, and we can select whether that transverse scan is parallel, to the floor, or, or whether we want it, in a different orthogonal plane, and, and that depends a little bit on, on which area in particular, we're interested in. The other beauty of low field magnetic resonance imaging as opposed to high field high field MRI is that we don't get.
The same problems with magic angle artefacts appearing in the DDFT in the distal portion. So when we're looking at at MRI scans, we not only can select the way that we acquire the slices, so we can build up different, a picture with different orthogonal slicing. But we also can select which type of MR sequence that we want to use.
And there are these, would be the, the most common types of MR sequence that we use when looking at scanning the horse's foot with a low field system. And the, the sequences that, that we commonly use are T1 weighted. T2 weighted, and there can be some subtle different types of T2 weighted.
But essentially, the, we'll, we'll consider those as one group. Proton denseity weighted sequences or stir weighted sequences. And the appearance of different parts of the foot appeared differently according to what, sequence that we are looking at.
In particular, If we, consider the appearance of, fluid, or, so we'll look here at joint fluid. On T1 weighted sequences, fluid, it appears dark or has a low signal. Whereas on T2 weighted and proton density weighted, it has a higher signal intensity, so it appears brighter and white on, on our scans.
And on stir sequences, appears very bright. Now, this can be useful, because in, most of the pathologies that we are dealing with, we are looking for signs of inflammation, haemorrhage, etc. And therefore, to have, fluid or water appearing bright means that it's, it becomes more obvious.
So, If we look here, what we know is that T1 weighted sequences, these have exquisite detail, but. We have a low signal intensity for water or so fluid will appear dark, and that means it can be very hard to appreciate areas of fluid accumulation that are. Occurring in other structures that also have a low signal.
So, when we're considering the deep digital flexor tendon, it's very hard on T1 weighted sequences to, appreciate fluid within the tendon, because both fluid and the tendon have low signal intensity and therefore appeared, dark. Conversely, when we're looking at T2 weighted, proton density weighted, or stir weighted sequences, fluid has a higher signal intensity, so it appears bright on these sequences. And therefore, is much more easy to detect within the tendon, where normal coaginous tendon would expect it to appear dark or to have a low signal intensity.
And for that reason, that is why, when we're acquiring a set of MRI scans of the foot or a region of interest, we not only acquire sequences. scans in, in different planes, but also in using these different sequences. Because this allows us then to build up information, about what we're looking at.
So we can get a lot of anatomical detail from T1 weighted sequences, but these are poor at showing. Areas of pathology. Conversely, at the other end of the spectrum, stir sequences are very good at detecting fluid and therefore, very good at detecting areas of fluid accumulation, and in, for example, with inflammation.
But we do, get quite a, a, a decrease in, the, the anatomical detail on, on these. And we're gonna look at some of these as we go through the talk. So these are just some examples of transverse scans with the different weighted different types of sequences.
So here, on the left-hand side, we can see T1 weighted sequence. So on this sequence, if we remember, fluid. Has a low water, has a low signal intensity, so appears dark, but we get good anatomical detail here.
We can see the typical bilobed structure of the deep digital flexor tendon. And these, sections are all taken at the same level. And these are all taken, we're just getting, a glimpse here through the collateral, distal sasmoidid ligaments.
So, we're looking here at the, or naviculpensary ligaments. So, we're just above the level, of, of, the, the proximal recess of the bursa. So here we can see very clearly, this low signal bi lobe structure, the deep flex tendon, and the arrow here is pointing to a clear, split or lesion in this tendon.
The, open arrow, head here is, is showing that we have just got a smaller, less discrete, lesion also evident here in this lobe. Now if we compare the appearance of, of the T1 scan to the proton density weighted scan. The proton density, is also a, a very nice scan, and, and is good for, giving us anatomical detail.
And it's also, it's almost a halfway house between T1 and T2 weighted. So it can be very useful, for, showing lesions and, and, and. Without the, loss of detail that we see in some T2 weighted and stir-weighted sequences.
So, again, the arrow here is, is pointing towards, an obvious lesion, in this lobe here, the deep flex tendon. When we consider this is a T2 weighted sequence. So on T2 weighted sequence, we have got some compromise, some loss of anatomical detail.
But here, fluid is, or water has a bright signal, so a higher signal intensity. So, it's good for detecting. Pathology, it's very easy to appreciate effusions, perhaps in the coffin joint or in the navicular bursa or other synovial cavities.
But it's also now giving us some information, about the fluid content of this, lesion. We'll go on to talk about that in a minute, but that helps us perhaps to tell us whether what we're actually looking at is a, a current active tendinopathy, or whether the lesion that we're looking at, is, is perhaps more chronic, i.e., more sort of fibrous tissue and, and scarring.
And again, here, on, on the stir weighted, again, we can see that we have quite now a, a slightly fuzzy, appearance to the scan. And that's not necessary because this is a poor scan. We do lose anatomical detail on stir weighted sequences.
But you'll also notice here that the fat, that, that is, contained within the medullary cavity, that fat signal has been suppressed. So, if we look here on the T2 and T, and proton density weighted, we have a high fat signal, here within the medullary cavity of the bone, and an intermediate signal here on the T1 weighted. Here on the stern.
The, the cortical bone and the medullary bone both appear to be of low signal, and that's because we've got suppression of the fat signal. And why that is useful is it then allows us to show if we have got, fluid within a bone. So very useful for, demonstrating areas of what are colloquially known as bone bruising, or, or indeed, fractures.
So these are why we have these different types of sequences. And, and, therefore, when we're looking at scanning a horse's foot, we, will acquire, as I say, a number of different sequences. So we'd usually always acquire a minimum of these 4 sequences in at least 3 different orthogonal planes.
So as we recall. Tendon is highly ordered, tightly bound, and a helical structure of collagen fibres. And this, has a low water content and therefore, appears on MR scans as a hypo intense signal, i.e., on all scans, irrespective of the sequence, it appears dark.
When we get accumulation of, damage, and this is often secondary to repetitive mechanical stress, hypothermia or hypoxia, we start to lose that tissue integrity and start to get, biochemical changes in the content of the tendon and, and its extracellular matrix. And this, basically, well, this, this leads to alterations, not only in the type of, of collagen ratio, but also, in the, it's, it's, The, the collagen cramp, as well as the collagen fibrile, diameter. And all these have impacts on the mobility and content of water within the, within the, tendon.
And therefore, we can then start to appreciate, areas of pathology on MRI scan. Inflammatory infiltrates, edoema, and neovascularization also impact the water content, and therefore, again, this is why we can then use MRI scans in order to detect, tendinopathy. Now there's an extensive overlap of the MRI features that are associated with the different stages of tendinopathy.
Basically, and, and, and simplistically, what we see is an increased signal intensity on our fluid sensitive sequences. So your T2 weighted sequences and your st sequences when you have active pathology, there. And so, that, as I said before, it's because, it's because of this reason that when developing, a musculoskeletal protocol, we it's really important that we, build into that a number of different fluid sensitive sequences so that we can see areas of, of active, and, and, current tendinopathy.
If we just relied on the T1 sequences, which will show, tendon pathology, give us very detailed information, anatomical information about tendon pathology. The, the reason, that we can't just use that is it becomes very hard to stage the, the tendon, injury. So, if we consider the phases of tendon healing and, and what we see, in that very acute inflammatory, phase, which is really within the first few hours or, or, or days, actually, it can, tendon injury can quite easily be missed on an MRI.
So, usually, we're in that proliferative, phase, where, we've, we've now got an increase in, in singularity, and, and, fibreglass, becoming, starting to, to, to, play. An immature, scar formation. This is when we start to see hyperintensity on the T2 and the proton density weighted sequences.
Therefore, allowing us to, to, to be confident in, in stating that we have. A, tendon injury that is, is sort of within the, proliferative phase, that proliferative phase phase usually lasts, somewhere between sort of 2 weeks and, and, and perhaps 3 to 4 months. Once we're through that proliferative phase, we're now into the sort of remodelling phase.
And what we start to see now is a regression, of the fluid signal. What we will see, and, is that you still get a persistent hyperintensivity on T1 weighted and some T2 weighted sequences because we still have abnormal collagen structure. And actually, what we find is that that high, signal on T1 weighted signal, often persists well into, the, the chronic stages of, of healing, and, and can, reflect that, the sort of, basically, what we are looking at is, is, tissue scarring, tendon scarring, if you like, there.
But generally, we're looking at, seeing a decrease in the signal intensity on T2 weighted and stir weighted sequences as a way of, assessing and, and looking at, how these, tendon injuries are, are healing. So let's consider the type of deep flexor tendon injuries we see within the foot. And here, we've got examples of the sort of 4 most common, injuries that we see.
Here, we've got, a core lesion, here that we can see this area of high signal intensity, within the, the, body of the deep digital flexor tendon. So, these are transverse scans, as, as previously. We've got this, what should appear as a, low signal bilobed structure of the deep flex tendon.
And we can see here, across in section, about 40% of the cross-sectional area of this lobe has high signal intensity. And this is a typical appearance of a core lesion. In other horses, we will, may see, more of a split.
So we tend to see sort of parasagittal split. And they can be full thickness or, partial thickness. So, in, in this case, we've got a full thickness parasagittal split that extends from the dorsal surface to the palmar, surface of the deep digital flex tendon.
Dorsal tearing here is, is another frequent, finding, particularly at the, the sort of naviculia, level, or just in the supra-navicular level. And we can see here that we have lost the sort of smooth, dorsal border of the tendon. Got rather sort of irregular, appearance with, with, some signal extending down into the, body of the lobe of the tendon.
So this is a typical appearance of a dorsal tear. Whereas on this scan, we can see, not dissimilar to the dorsal tear, but perhaps just more subtle. So, instead of having a nice smooth contour to the dorsal ward of the lobes of the, tendon, we can see that we have got sort of irregularity, or dorsal fibrillation here.
So these are just some examples. This is a, a, a low field, . MRI scan, showing again, we've got a short dorsal split.
And if we look at these, postmortems, so here, this is, we're looking here at the flexor surface of the navicular bone here, which you can see, we've got quite marked concurrent, navicular bone cartilage, lesions with fibrocartilage lesions. But if we look here at the deep digital flexor tendon, which has now been sort of reflected back, so we're opening up, that to, to look at the dorsal surface. You can see this, would be the, the, the gross appearance of these dorsal, border splits.
This is a postmortem examination, of a parasagittal split. So, here we're looking, again, this is the, deep digital flex tendon. So, again, we've opened this out, and sort of, reflected it.
So we're now looking down onto the, the dorsal surface of the deep digital flexor tendon. And we can see, here that our, our forceps are, probing into this, parasagittal split, that we can clearly see here. And this is the appearance of that such a lesion, would appear on, an MRI scan.
So, again, we've got a full thickness, parasatal split shown here by the arrow. Core lesions. So this, is, is a scan that is, is taken in, in a frontal plane here.
So this is just at the level of the insertion or just before, the, tendon inserts onto the disc. Or phalanx. So here, this is the outline of the deep digital flexor tendon.
And we can see very clearly here, in, within, this, lobe at the, insertion of the digital flexor tendon, that we've got this, core lesion, this, large area of high signal within the tendon. This, is, is the appearance of that same, . Area at postmortem, so we're looking at the deep digital flex tendon here, we can appreciate it's enlarged, we can appreciate that, here in our MRI scan, and this is our area of pathology here.
This, lesion actually extended quite a long way, approximately. So we are now above, the level of the navicular bone, and we can still see that, we've, we've got this large core lesion, still filling quite a significant, proportion of this, lobe of the deep digital flexor tendon. And again, if we look here on our er gross specimen, we can, we can see the, the appearance of, of that again at postmortem.
So MRI has really helped us to become much more aware of these lesions and, and we can diagnose them much more readily. But what with this information, what's do we then recommend in way of treatment and what, evidence is there for the different treatment modalities? So, certainly, you know, our, our initial, rationale for treatment should be that we want to, Devise or recommend a system that allows for appropriate mechanical loading of the tendon.
And so, this is certainly, in all cases, going to, as with any tendon injury, involve a period of rest, and then a, a period of controlled exercise and, and rehabilitation. As with any foot, pathology in the horse, it's really important that we optimise the foot balance and consider different types of shoeing, perhaps, to try and decrease, some of the, the tension, through the, the deep digital flexor tendon. We also want to reduce scarring and ideally promote tendon regeneration.
And so this is where the intralesional and the intrathecal use, of injection of biologicals comes into play. And we'll look a little bit more at some of the, evidence and and research for that. Very often, when you have a, deep flexor tendon pathology within the foot, we get concurrent synovitis of, particularly the navicular bursa, sometimes also of the, or often also, actually, the, of the distalinterphalangeal joint.
And certainly, reducing concurrent inflammation in the bursa. Is, is important. And so, this can be, with intrathecal medication of the navicular bursa, or, endoscopic debridement of, damaged tendon, with the aim of, of reducing concurrent inflammation within the navicular bursa, and thereby reducing pain.
And also, analgesia, is, is important, you know, ultimately, these horses are presented to us for lameness. So what can we look at doing, just to, reduce the pain? And we'll have a little bit of, have a look at the, end of this talk about whether Palmer digital neurectomy, has a place in, in, the, the rational treatment for tendon injuries.
So starting with rest and controlled exercise, it's generally considered that a prolonged period of rest is paramount in the treatment of these injuries. How long that period of rest is, is gonna be really determined by the severity of the injury. And, and the type of injuries.
As a general guide, I think that, core and parasagittal lesions are generally, we're gonna be looking at confinement in a stool or a small pen for somewhere in the region of 6 to 12 months. And as with, tendon injuries, more proximately, so, metacarpal tendon injuries, a controlled slowly ascending exercise regime. Is as important, in the rehabilitation phase.
We tend to, very much, I think, generally in equine practise, tend to sort of think of, everything needs to be done within 12 months, because that's often our insurance window, and, and, and often, after 12 months, then, then, you know, insurance, cover is, is, comes to an end. But I think that certainly, some of these more severe deep flex tendon injuries, we should perhaps be, considering laying them off for even longer. And, and some of them, I think, may take, you know, 18 months, possibly even, 2 years, would not be unrealistic to, expect these horses to have as, as time out of competition.
So what, with just rest and rehab alone, what sort of results can we expect? Well, if we look back into the literature. There are a number of, of sort of key papers that, are looked at, outcomes and response to treatment in horses that had.
Deep digital flex tendon diagnosed with MRI. This paper, from the, EVJ. They found that if, when you looked at, of their 199 horses, reviewed in this paper, 47 horses had primary tendon pathology only.
So if we consider those 47 horses, 22 out of 47. So 47%, just under half of these horses came sound. However, when we looked at how many of these horses with a primary DDFT lesion, returned to work, less than a third of these horses, roughly 28% of these horses actually came back to athletic activity.
And certainly, of the, 18 horses which had, combined navicular bone pathology and DDFT injuries, the, results were worse, with only 1 out of 18 horses, actually, that, did not remain persistently or recurrently lame. So quite depressing results. Long time ago now, that, but I, reviewed, the, the data that we had, from the Lipi equine Hospital, for a beaver, presentation.
And, certainly, for that talk, we had, 55 horses where we had follow-up information on those horses which had primary DDFT injury. That was managed just with rest and controlled exercise. So, no other, intervention.
And the, the duration of that rest period, really ranged, from anything from 3 months to 4 years. But when we looked at our results, we found very, very similar results. Just under half of those horses returned to soundness.
So 49% of horses came sound. However, only 25% of those horses returned to their previous level of activity. 9% were mildly lame but still in use, so were able to be used at a lower level.
Another bigger study, from a multicenter study, considered 168 horses with primary tendon injury. Of these, 25% of horses returned to their previous levels of athletic activity. And horses with complete splits or core lesions were much less likely to return to their same level athletic activity than horses with dorsal border splits.
So, these three, studies all actually had very similar results, which I think roughly 50% of horses were coming back to SANA, but really only about 25 to 30% of horses were getting back to their former level of athletic activity. In this study, retrospective study. They are considered 34 horses which had primary DDFT pathology.
Interestingly, in this, in this study, no horse with a lesion more than 3 centimetres or a lesion greater than 10% of the cross-sectional, . A cross sectional area of the tendon, evident on T1 weighted sequences, returned to their previous athletic activity. And not surprisingly, perhaps, horses which had concurrent, pathology.
Maybe with concurrent navicular bone pathology had a worse outcome than with horses with deep flexor tendon pathology or alone. So, certainly the, the outlook with just rest and rehab is, is is not that optimistic. I think with rest and rehab, it's always, important to consider the remedialarry.
It's really important that these horses have a good dorsal palm and lateral medial footing balance, and that this is either corrected and or maintained during that rest and rehab period. Whether or not, the, you elect to use some sort of heel wedge or raised heels, which will help to reduce the strain on the deep distance of flex tendon, I think very much that decision has to be taken on a case by case basis with, Considering the the, the horse's natural for confirmation, the natural size and and structure of the frog. So I think that, that for some horses that have perhaps very low heel con confirmation, very, thin, poorly developed frog and digital cushion, that, that, can be useful, and those horses were perhaps a more upright, more boxy for than, than it may just be that we, just need to get these horses well balanced, well set up, and, and ensure that we optimise the position of breakover.
So, really, as we've said, that the, the, the prognosis is, is not that great with, with rest and, and rehab alone. So, can we, can we improve on this? Can we do any better?
And, gonna look a little bit at, at some of the other, commonly used, treatment modalities and, and some of the evidence around that. Certainly injection of corticosteroids with or without concurrent injection of hyaluronic acid into the navicular bursa. We're gonna consider injection of biologic agents into the bursa or indeed directly into the tendon.
What is the benefit of navicular bursoscopy and debridement of tendon lesions and also consider whether or not, perhaps we might not be better off just neurectomizing these, these cases. So firstly, when we're considering injection of the navicular bursa with corticosteroids. We go back to this study, and, in, in this study, 21 of 35 ft with digital DDFT, injuries had the navicular burst and medicated with trisillo.
They found that 66% of their horses returned to work in 2 to 4 weeks with no recurrence of lameness for three months. So on the face of it, that is a considerable improvement, compared to some of the, the other, retrospective studies that we were looking at. However, What they actually, when we look closer into that paper, we found that the mean duration of, soundness was only about 7, just over 7, months.
And there was a very high recurrence rate of, lameness in those horses. So I think that whilst using, steroids may thickly into the bs and may be useful if a horse has a particular event or competition that they want to try to get to that season. Actually, the, studies would suggest that in, in the long term, that, that horse, is, is very likely to, have a recurrence of lameness.
And I guess that's not really altogether surprising. If we, consider bursoscopy and endososcopic debridement of, the torn fibres, . Basically, it was, suggested on, on the premise that actually, the, the, body has very poor capacity to, to, to repair or to heal, torn fibres in a synovial environment.
And these torn fibres are less, contributing to persistent synovial irritation and inflammation, and therefore, pain. Really due to this lack of any sort of intrinsic repair mechanism. And so therefore proposed that by debriding these torn and extruded collagen fibres, we are suppressing synovial inflammation.
And Susan, initially, the results, that, that were presented, by, Matt Smith and, and Ian Wright, they, looked, certainly looked very encouraging. They found that, of, 92 horses treated with full up on 65 horses. That about 54% of those horses went back to their previous level of work.
But, and, with 9%, coming sound and back to a reduced level of work. But still, following surgery, in their study, about a third of those horses remained la. I think that, this study led to a lot of, people advocating, this surgery, and it became very popular.
I think that, generally, experience has found that, perhaps the results are not as, optimal as, as, that this might suggest. And actually, if you look down at this, many of the lesions that were treated in this study are, were incredibly subtle cases, of fibrillation. A retrospective study of, the versoscopy, of the horses, where this was performed, on horses with DDFT lesion at the leper equine Hospital, was, was done.
And, this was, was a, a, a, a short study, that, was put together by, one of my colleagues, Tom Hughes, the horse is undergoing, navicularbustoscopy. And, Sorry, those dates should read June 2014 to December 2015, so 20 horses over an 18 month period. And in this study, again, we found that, 6 out of 16 remained lame.
10 out of 16, so 62% of these horses, returned, to work. In one horse, lameness, recurred, and in two horses, lameness occurred in the contralateral limb. So, again, in this population, slightly better, outcome than, than, with rest and rehab alone, but still not brilliant.
That, then I think, people have, have begun to turn to, asking whether we can use stem cells or other biologics, with the rationale of improving the quality of, of tendon, regeneration or, or tendon repair. So, with the, rationale for using stem cells is to aim to promote scar-free healing. Of the injured tendon and therefore preserve normal tendon elasticity, which is, is, obviously not the case when we, get a fibrous scar.
And a number of different, mechanisms of delivering, stem cells into the required region have been, looked at and tried and recommended. So that could be in tenderness, injection of stem cells under arthroscopic control. In tenderness injection, done under CT control.
Some people have tried, intratenderness, injection using radiographic control or transcuneal, ultrasound, control to, ensure that injection is, is, occurring into the, right place. And indeed, some people have looked at regional, tried regional perfusion. But as I think with a lot of biologics, there is a very limited amount of of good data as to the efficacy of this.
So, Michael Schrammer, during his time, at North Carolina, did a retrospective study of the use of stem cells and 29 horses. We do DFT tests. And 23 of these horses underwent basoscopy, and then treatment of the lesion with stem cells.
In 17 horses, the stem cells were introduced inlegally, and 6 they were, deposited into the, navicular bursa. The majority were bone marrow, derived stem cells, although fat-derived stem cells were used in 5 horses. And this study encompassed a range of lesions with core lesions, predominating, but also some horses with dorsal lesions or what were termed mixed lesions.
In 6 of the horses, they had me stem, mesocarnal stem cell injection without surgery. And, this was these equal mixture, 3 horses with bone marrow derived stem cells, and 3 with fat derived stem cells. Again, quite a mixture of lesions.
All horses then had 6 months of box dress, followed by a gradual controlled return to exercise. So, if we, look at these, horses, we had 29 horses in the study, that, follow-up time was somewhere between 6 months and, and, 5 years. So in horses, here we had, .
Horses that had, stem cell treatment. We had 3 horses that were sound for intended use. One horse was sound, but came back to a lower level of use.
2 horses that remained persistently lame. Well, a stem cell was combined with basoscopy. 28% of those horses were sound.
38% of those horses returned to a lower level of use, and a third of those horses remained lame, so roughly 1/3, 1/3, 13. So, really on the basis of that, not good convincing evidence that actually the use of stem cells can be recommended in these horses. We're looking, so, actually, what we're beginning to see again is rather a disappointing prognosis in all of, these cases.
So should we just, be considering neurectomizing these horses as a way of, getting them back to athletic activity? This is a study that looked at the outcome of using neurectomy in horses, in 50 cases, sorry, in, in 50 horses. And in this study, they found that lameness recurred much earlier in horses, which had a core lesion or a linear lesion of the deep digital flexor tendon.
Usually, lameness recurred with a median time around a year. And that, recurrence was earlier in those horses compared to horses with dorsal border fray. Where the median time for occurrence of lameness was, was 2 years.
Or in horses, indeed, that had other foot pathologies, so no DDFT lesion. Again, that was just under a year, median time. And what they found, was that when looking at these with MRI scan, that there was a progression of the DDFT lesion once, ridden activity was resumed.
So, a little bit, like a ladder extending up a A pair of tights. They found that, when these horses were neurectomized and therefore ridden, that at, and, and, and, ridden that without, if you like, the protective vector pain that ongoing, tendon damage ensued, and, and, and these lesions were extending, which I guess is, is really of no surprise. So, what is the best way of, of, of, you know, what do we recommend for, for treating these?
I think when we diagnose any deep flex tendon injury, that, we, it is important, firstly, to look at the foot, to trim the foot and to ensure that we maintain good foot balance. So, we're getting good biomechanical, set up there. I think then, depending on the nature of the lesion and the extent of the lesion, will slightly depend upon, our, our recommendations.
But with the more severe lesions, the core lesions, and the parasagittal splits, I think that essentially we are looking at a prolonged period of rest with controlled walking exercise. Possibly, with some intralesional, biologics, but I think the evidence is poor for that, and, and certainly, the, the cost-benefit ratio, it, it is quite difficult to, recommend that. Whilst intra, faecal injection of, Corticosteroids may help to get these horses back for the short term.
I think, again, if we're looking at trying to, get these horses long term sound, that, that there is probably little benefit of intraversal medication. Dorsal tears and, and fraying or fibrillation, I think these are, generally, considered perhaps to be the less severe. I think these are cases where perhaps, there is a role for, intraversal medication.
Burs bursoscopic debridement, again, there is a rationale for its use. I think the, there is some suggestion that there may be limited benefit, to, surgery. And, and certainly this is, you, with, with phangal fibrillation and persistent lameness, those would be the horses that would be considered to be better candidates for a neurectomy, than compared to the, the horses with core lesions or parasagittal splits.
So in conclusion, I think the overall, the prognosis for return to former athletic use for horses with DGFT injuries in the foot is still poor, particularly those horses with core lesions and full thickness splits. Burstoscopy may have a role in horses, with dorsal splits, but there's no currently, sound evidence that, that mesenchymal stem cells will improve the outcome. I think, as with many of these studies, much bigger multi-center studies are needed to best, evaluate treatment protocols, and particularly when considering use of, of, of the biologics.
I think that is a rationale for repeated MRI examinations in order to monitor, tendon healing in much the same way that we would use ultrasound scanning in order to monitor tendon healing for metacarpal, tendon injuries. And, and I think that by Doing that, we can then adapt the horse's rest, and then, and then it's exercise programme on a case by case basis. Thank you very much for your attention.
