Ask the vet: Tendon & Ligament Injuries and Rehabilitation.

Has your horse experienced a tendon or ligament injury? Pose your questions on the topic of tendon and ligament injuries and rehabilitation for our AAEP expert, Dr. Rebecca Linke.

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Question: Our 13-year-old Holsteiner tore his left hind oblique sesamoidian ligament. This was diagnosed in early June following a year long quest to determine the cause of a transitory lameness (and injections to many joints including neck, SI joints, stifles, hocks and coffins). Treatment consisted of two sessions of shockwave therapy that were 2 weeks apart and hand-walking for 6 weeks. Tack-walking was then for an additional 4 weeks and a slow build-up of work. He is now up to a full 45 minutes of flat work including trotting and cantering. How long should it be before we can get back to jumping? He was being used as an equitation horse doing 3'6" to 4' medals. Following an injury like this, can he ever be expected to go back to the same level of competition?
Answer: 
This is a question we hear a lot: "will my horse ever return to the work he was doing prior to his injury?" Unfortunately, there is no way to predict which injuries will recur and which will not. It sounds like you and your veterinarian have done the right thing for your horse so far, combining rest, gradual return to work, and shockwave therapy. Continue to work with your veterinarian to determine when is the best time to reintroduce jumping, starting with ground rails and low cavaletti and working up to a goal determined by your veterinarian. The more gradual the return to jumping, the better for your horse. I haven't been able to find a percentage of these injuries that recur, but unfortunately Ross and Dyson (Lameness in the Horse, 2003) report that "the incidence of recurrence of oblique distal sesamoidean ligament injury is high". Because of this, you and your veterinarian may decide that it is best for your horse not to try to return to his previous level of athleticism, or perhaps even find another job that is less physically demanding.
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Question: I live in South Africa and this morning my veterinarian recommended your site in regards to which boots to use on a horse that had a deep superficial flexor tendon injury on his near fore just over a year ago. He was rested for almost 9 months and given PRP treatments three times. I was told the AAEP recommends a certain type of boot for work after this kind of injury. His tendon is cool to the touch and unless one is an expert one would not see that there had been such a drastic injury. I intend to have him scanned again as the thought is to put him back into racing, or is this a very bad idea? Your comments would be much appreciated. 
Answer: 
I am a member of AAEP but I am not an employee. However, AAEP does not endorse products of any kind. I have merely volunteered to answer questions on this topic because I feel that I have had some experience with these types of injuries during my veterinary career. 

It sounds like you have done everything you could for your horse in the hopes of getting him back to the racetrack. I would absolutely agree with having an ultrasound performed on him before he is cleared for this kind of work. One thing you haven't mentioned in your question is whether your horse is a Thoroughbred or a Standardbred, as this may affect whether he is able to return to racing and how successful he may be there. The majority of my experience is with Standardbreds, and in my experience, they have moderate success in returning to racing, even with as severe an injury as you have described. My other question is whether the injury involves the deep digital flexor tendon as well as the superficial digital flexor tendon; you described it as a "deep superficial flexor tendon injury," which I must interpret as being deep within the superficial digital flexor tendon, although that tendon is not usually very thick. Without seeing the original ultrasounds and also the current scans, I'm afraid I can't tell you what his prognosis is for returning to racing. Equine Sports Medicine and Surgery (Hinchcliff, et all, 2004) recommends Dalmar support boots for use after tendon injuries. These boots are designed for use in the exercising horse, but I don't know if they are compatible with horses that are racing, as that is one of the highest levels of performance. If you choose to try these boots on your horse, I recommend that you investigate how he works in the boots extensively before asking him to race in them.
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Question: My 17-year-old Quarter horse mare bowed the tendon low in her right hind leg in May of this year. Our vet completed a sonogram which revealed an already healing lesion. She has been confined to a small turnout area and separated from the other two horses for the last 5 months. There is some swelling at the fetlock joint, but the leg has never been hot. We applied liniment and polo wraps for 4 weeks. She is showing improvement, especially in the last 3 weeks with being turned out in a small area to graze alone. My vet has suggested re-evaluating in December and proceed from there. Any other suggestions, supplements, treatments we may have missed?
Answer: 
Tendon injuries can be frustrating because they take a long time to heal, may or may not resolve ultrasonographically, and may carry the risk of reinjury for a significant time after the original injury. There are a few therapies that are used to try to increase healing and decrease the length of time needed to return to work, but there is really no safe way to rush a tendon injury. Your veterinarian can discuss with you whether your mare is a good candidate for treatments such as stem cell therapy and extracorporeal shock wave therapy. Supplements are available that claim to support tendon and ligament health, and certainly some supplements, such as antioxidants, support the general health of the animal, but supplements are not a substitute for proper veterinary care. Some of these injuries respond best to conservative therapy, such as time off and then slow return to work, with or without nonsteroidal anti-inflammatories, and your veterinarian will be best able to determine the best course for your mare.
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Question: My horse has continued with bouts of reoccurring lameness. I would find swollen hind fetlocks and would commence to ice, bute, wrapping and rest. She would be fine and I would start her back on light work, but after several times of the lameness coming back, I contacted my veterinarian to do a work-up. An ultrasound showed slight tearing with no noticeable difference right to left in the SDFT as far as swelling. She was sent to the paddock for the next two (2) months, to begin hand walking in one month. He administered ace to keep her calm and DMSO on the joint capsule. When I read up on this type of injury, it seems that it can easily reoccur once it has been weakened. We do nothing more than walk, trot, canter in the ring and the mare has five (5) acres of turnout. Would stem cell or some other type of therapy give me a better chance for recovery?
Answer: 
This is also a good question, but more information is needed to be able to answer. First of all, how old is your horse, and how long have the bouts of lameness been going on? How long would the bouts of lameness last? Certainly tendons and ligaments that have been injured or have shown fiber disruption are often prone to reinjury but unfortunately, it is impossible to predict which ones are more likely to reinjure. Certain factors, such as the severity of the original injury and the intensity of the work program that your mare returns to may have an effect on whether or not she may reinjure her tendon. Your veterinarian would be best able to assess this injury both by how lame your mare is and also how much disruption there is in her tendon, and help you decide whether this is a case that would benefit from stem cell therapy or not. Often if there is a small amount of tearing or fiber disruption there may not be a "hole" into which to inject something like stem cells or PRP, and the injury can successfully be managed conservatively, as you're doing.
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Question: I have a 4-year-old mare that sustained a puncture injury to the back of her pastern. It went TO the tendon but not through the tendon. Subsequently, an infection popped an abscess at the top of the tendon sheath, which allowed us to drench the length of the wound and the sheath with antibiotic fluid. We did this for several days in a row until the wound did not open through. She was on stall rest and daily bandage changes with several courses of antibiotic treatments. She apparently had infection off and on for at least 3 or 4 months. During this time she was also on higher doses of bute that tapered off along with Ulcergard since she lost a lot of weight. 

She has been ultrasounded 3 times and one of my vets believes she will make a full recovery. The other vet is hoping for pasture sound and pain free. The ultrasound does not show any significant ligament damage but the last one showed a couple of areas that were still healing deep within her leg. Treatment was to leave her on pasture rest for 6 months and then start light riding. 

My concern is the fetlock is much larger on the injured side and also the pastern angel is steeper. I'm not sure if there is something else I should be doing. The vet thinks the larger fetlock is due to scar tissue and doesn't seem to be worried about it. But it does come and go in size and is not painful when palpated. The entire area seems mostly pain free. She does still slightly favor the leg when trotting or slight loping. She won't lope for a long distance but still does buck on occasion. This horse was being ridden at the time of injury in February 2013. Is there anything else I should try or be doing? 

When she was injured in February of 2013, she spent 5 months in a stall with daily dressing changes. It took this long for the initial wound to close. This was up and down period with varying degrees of pain for her with swelling. She was on multiple antibiotics off and on during this time to treat both aerobic and anaerobic bacteria. She was on bute the entire 5 months. Since July she has been pastured. She has responded well to all treatments.The two vets we use are partners in the same practice and both have seen her.
Answer: 
That sounds like a very serious injury and one that may be difficult to recover fully from. My main concerns with this injury are the extensive and lengthy infection and the change in pastern angle. The swelling in the fetlock may be due to either scar tissue or edema caused by decreased circulation, which may be a result of the original injury. It sounds like you and your veterinarians have taken the best possible care of this mare, but it may be difficult to be sure that the infection is completely cleared up, even after all your hard work. I am concerned that the swelling is still changing, rather than just staying one constant size, but the fact that it doesn't seem to bother your mare when you palpate it is a good sign. My concern with the change in pastern angle is that if the fetlock is dropping, it may indicate damage to the suspensory apparatus. With regards to further treatment, it sounds like you and your veterinarians are doing just about everything this mare could need for a successful outcome. Shockwave therapy may help at this point, but without seeing the patient and the ultrasound images, it's difficult to say what her prognosis may be. Conservative treatment sounds like the right way to go. Your veterinarians are absolutely right in advising you to give her six more months turned out before thinking about putting her back in work, and I'm sure they're going to want to reassess her soundness level at that point before they clear her for even light work. I agree, pasture sound is a good goal to work towards, and it is difficult for any of us to say how sound she will be or how long it will take to get there.
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Question: I own a 10-year-old Quarab gelding that presents swelling at the top of the rear pastern, but shows no lameness. The swelling has shown no improvement after two weeks of home treatment. My veterinarian does not own a portable radiograph or clinic radiograph machine for horses. I need to haul him. Should I go direct to the University vet school, or a veterinarian at almost half the distance that has imaging equipment, but is not an "equine hospital"? Or should I give it more time and continue with the home treatment? He was not "in work" when the injury occurred and his job is mostly a pasture ornament with very little trail work.
Answer: 
I'll do my best to answer this question with the limited information given. First of all, is the swelling hard or soft? This will help you and your veterinarian to decide whether it would be better to take xrays first, or to ultrasound it first, although the information that the horse is sound makes me lean towards ultrasound as the first choice for diagnostics, since it is rare for a horse with a bony abnormality to be sound, although it is possible. This is why it is difficult if not impossible to answer these questions without seeing the patient. Is the swelling hot or warm, and is it painful on palpation? Was there any trauma observed that caused the injury, like a kick from another horse, a bad step or trip, or playing rough with pasture buddies? This will help you to decide how recent and how severe the injury is. Frequently, we wait at least three to five days after injury to perform an ultrasonographic exam, as this allows time for the surrounding soft tissue swelling to go down, which lets us get a better view of the structures we're trying to assess. What is the "home treatment" that the horse is getting? There are many options for this, including stall rest and/or handwalking, treatment with nonsteroidal anti-inflammatories such as bute or banamine, cold therapy, and poulticing or other types of wraps and pressure bandages. Has the horse shown any improvement at all after the home treatment? How far of a drive is it to the nearest university vet school, and how far is it to the local clinic? Does the local clinic concentrate on horses even though they are not an equine hospital, as you reported, and are you comfortable with the level of care that your horse would get there? Finally, you must decide what your goals are for this horse and how rapidly you want to achieve them, and to this end how much money and time you are willing to spend. If the horse is sound and comfortable, and you are satisfied to keep him at home and take the "wait and see" approach, if advised by your veterinarian that that is an acceptable option, than certainly do that. If you would rather try to get an answer as to what is causing the swelling and how best to resolve it, then you may want to consider shipping the horse to a facility that can help you get these answers. There are many options for dealing with swellings such as these, and the most important thing to consider first is the health and safety of the horse - above all, we want to make sure that we're not dealing with an injury that may get worse if it is not treated properly. Your veterinarian can discuss with you what is the best option for you and your horse.
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Question: I have a 13-year-old, 14.2 hand pony on rehabilitation following a tear in her left hind annular ligament (fetlock area) during August. She was only ever lame at a trot. She has recovered very well and has been on walk road exercise for one month and some trot work for two weeks. We are just starting to introduce a little canter work. She is still on box stall rest to avoid injury in the field but I am hoping to get her out during the day anytime soon. Are there any specific exercises that would benefit her return to jumping and anything to avoid?
Answer: 
With any type of soft tissue injury, slow and steady return to work is the key. As you've probably discussed with your veterinarian, your pony should not be turned out in a big field where she can re-injure herself until she's almost back to full work. You can talk to your veterinarian about possibly turning her out in a small paddock or round pen, especially if she's quiet and doesn't usually run or play much, to get a little more exercise in a somewhat controlled setting. You probably started the trot work on the straightaways and gradually added turns, and tried to keep her on a firmer surface and out of any deep footing or sand, which would put more strain on her tendons, ligaments, and other soft tissue. I often advise owners to add either one minute of trot work per day, or five minutes per week, so you gradually work up to thirty minutes of trot work per session, and begin canter work when you have reached thirty minutes of trot work. Avoid sharp turns, especially at higher speeds. It's a tedious process, but necessary to allow the structures to heal while reducing the risk of re-injury.
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Question: Are there any supplements that can help with rehabilitation? We have tried homeopathy and different types of physiotherapy, which have worked, but maybe there could be supplements, (except C and collagen, and devil's claw) that could help during the first weeks?
Answer: 
There are many supplements available that are intended to support tendon and ligament health. As you noted, antioxidants like vitamin C and vitamin E are important, as well as collagen and other building blocks such as MSM. Amino acids, L-carnitine, and creatine may help support muscle function, which may take some of the strain off of other soft tissue structures. Hyaluronin, polyglycan, glucosamine, and chondroitin may help support joint health. There are also Chinese herbal supplements available to support certain tissues within the body, including tendons and ligaments. As with any dietary supplement, these are not a substitute for a good feeding program, and they should not be used as a substitute for veterinary care, but rather used in conjunction with regular visits from your veterinarian they can help support a program that addresses your horse's needs. Consult your veterinarian and remember that supplements are not proven to treat any conditions, but may be part of a protocol that ultimately benefits your horse.
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Question: With a suspensory injury, does the lesion ever fill in or look normal on ultrasound after rehabilitation? What are the chances of re-injury?
Answer: 
Both of these are excellent questions, and unfortunately both vary depending on the individual case. It is possible for a suspensory lesion to fill in, given enough time, but sometimes they persist on ultrasound even a year or more after the original injury. Certain therapies, such as the injection of PRP, can cause a lesion to fill in ultrasonographically, although the ligament may still not be as strong as it was prior to the injury. Sometimes the lesion may fill in with slightly different tissue fibers, which causes it to remain visible on ultrasound. In certain cases, the ligament may contain muscle fibers interspersed throughout the structure, which may make interpretation of the ultrasound difficult, both before and after injury and rest and rehab time. This is more commonly found in hind suspensory ligaments. The potential for re-injury depends on many factors, such as severity of the injury, therapies used during rehabilitation, length of time before return to full athletic function, and intensity of training.
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Question: I have a 14-year-old Quarter horse gelding that I use for English flat and western pleasure along with horsemanship lessons and show him. He came up lame on his right front beginning last January. Radiographs showed he had bone chips in front of his fetlock joint, which we thought needed to be removed. After diagnostics, the veterinarian did not feel the bone fragments were the problem. The MRI showed soft tissue damage including the ligament that attaches to the coffin joint was enlarged three times it's usual size and there was swelling of the navicular bursa. To date, he has had radiographs, ultrasound and a MRI. The fetlock joint was injected and the navicular bursa and coffin joint were also injected with no results. We have tried stall rest, and bar shoes neither of which have worked. Any suggestions?
Answer: 
As you have found, this can be a very frustrating problem, and yours is complicated by the fact that there were bone chips found on x-ray. It is not uncommon to find bone chips in the fetlock joint that are occurring coincidentally and are not actually the problem, which is sometimes disappointing because the owner and the veterinarian both want to be able to remove the chips and solve the problem, but the chips are not the cause of the lameness, so the search must continue. There are many small but important structures in the foot that can often be the cause of the problem, and I'm glad that you and your veterinarian pursued so many imaging modalities to get a good idea of what the actual cause of the lameness is. You're probably talking about either the impar ligament of the navicular bone, the medial collateral ligament of the coffin bone, or the collateral ligament of the coffin bone - in any case, as you have found, these structures are difficult to image without MRI and just as difficult to treat, since they are, to some extent, enclosed within the hoof capsule. They are also, unfortunately, slow to heal in most cases. Stall rest, bar shoes, and NSAID (bute, etc.) treatment are all good therapies for this type of injury. Your veterinarian may also want to suggest extracorporeal shock wave therapy, and possibly therapeutic shoeing to raise the horse's heels. In severe cases where further degeneration is less of a concern, a last ditch treatment may be to cut the palmar digital nerves ("nerving"), but this should only be done when all other treatment methods have been exhausted because of the potential for complications.
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Question: My 18-year-old horse tore 60% of his deep flexor tendon. We are five months into recovery. Will he ever be able to jump again or do these injuries have a tendency to tear again?
Answer: 
This is an excellent question and one I often get from my clients. Unfortunately, each case is individual and there is no way to predict which injuries will recur and which will not. It is widely accepted that stall rest, "active rest", and a slow return to work are all very important in cases like this. The larger the lesion, the worse the prognosis is and the more likely the horse will re-injure the tendon when he resumes work. Front limb injuries have a better prognosis than hind limb injuries, but adding extracorporeal shock wave therapy during the rehabilitation period may improve the prognosis in hind limb injuries. Traditional support bandages like polo wraps don't actually help support the tendons during exercise, but there are new support boots on the market that may in fact help support the tendons during and after the rehab period, which could help prevent re-injury. These cases can sometimes be "heartbreakers", because it is possible to give the horse all the time he needs, bring him back to work very gradually, and still experience a re-injury, despite taking all possible precautions.
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Question: My horse currently has swelling on the outside of her carpal joint and advanced arthritis in the radiocarpal joint. The swelling was diagnosed as 'Carpal Tunnel Syndrome,' and following a scan, the Superficial ligament was thought to be the problem. The swelling frequently comes and goes and my horse is only walked out a couple of times a week - any schooling results in noticeable lameness. On light work, the veterinarian confirms she is sound (she was rested for 7 months and is on monthly injections of Carprofen). My question is what are your experiences of Carpal Tunnel in horses and is this frequently seen in horses with arthritic changes in the joint?
Answer: 
You're probably referring to an accumulation of fluid within your mare's carpal canal, which is a structure that surrounds the superficial and deep digital flexor tendons at the area of the horse's carpus, or knee. There are many potential causes of this swelling, but unfortunately without viewing your mare's radiographs and ultrasound images, it's impossible to say exactly what is the cause here. In her case, it sounds like she has two potential issues: her arthritic changes, and the 'problem' with her superficial digital flexor tendon. Either one of these issues may cause lameness on their own, as well as causing fluid to build up within the carpal canal, which could potentially contribute to her lameness. Your veterinarian will be best able to determine which is the most likely cause of the accumulation of fluid, and how best to address it. Arthritic changes are usually changes on the articular surfaces of bones, which would be treated differently from tendon damage, since in general mild arthritis is treated with mild to moderate amounts of exercise, while horses with tendon or ligament damage are frequently rested. Carprofen is one non-steroidal anti-inflammatory drug used to treat pain and inflammation caused by arthritis and/or tendon and ligament damage. Another commonly used anti-inflammatory is phenylbutazone, or "bute". Your veterinarian may also recommend injecting the carpal canal with hyaluronic acid and/or corticosteroids, which can often alleviate joint effusion and the inflammation that causes it.