Ask The Vet: Orthopedic Surgery - May 08

This depends on which way the leg is crooked. If you look at him from the side and it is crooked then this would be over at the knee or “goat knee”. If you look at him from the front and he is crooked this would be a carpal valgus deformity. I will suspect your problem is the latter but will address both issues.

Carpal valgus is a conformational flaw in which the limb goes outward from the knee down when observed from the front. We have discussed many conformational flaws in this forum and I finally have one that can be surgically corrected. Two questions for you. How old is the colt? And how severe is the limb deformity?

If 2 months of age or less and the degree of angulation is less than 10 degrees, then sit tight and see if it will straighten. If over 4 months of age, have your veterinarian examine the colt and take radiographs. Based on these findings, we can chart a course of therapy.

There are 2 common surgical procedures that can help here. One is periosteal stripping and the other is called transphyseal bridging. Either procedure is helpful to straighten a leg with carpal valgus. I prefer transphyseal bridging but other surgeons may prefer periosteal stripping. Check with your surgeon for their preference. For either of these procedures to work the colt should be less than 6 months of age. If older than 6 months, transphyseal bridging is the best procedure. Bridging surgery requires general anesthesia (as does periosteal stripping). The difference is with bridging you will need to remove implants (screws,wires,staples) when the leg is straight. With stripping surgery, no further surgery is required.

If over at the knee (goat knee), then likely no surgery is required. Sometimes we cut the superior check ligament in severe cases or a tendon in very severe cases. Most of these resolve spontaneously or with the aid of full limb bandaging +/- splints and stall confinement. Time is on your side with this problem. You can do the surgical procedure up to 12 to 18 months of age and have success. The valgus deformity needs to be addressed by 4 to 6 months of age to allow time for the leg to correct.

Have your veterinarian examine the colt and render an opinion regarding surgery. Things can be done. There is a window of opportunity on growing foals in regard to how successful we can be with surgery. Your farrier may be correct. Sometimes they do correct themselves.

This is a good question regarding etiology or what causes medial femoral condyle subchondral bone cysts to occur. This is a Hannoverain that is 7 years old. For years we have considered these cysts as a manifestation of osteochondrosis. In most cases, this is the cause. Osteochondrosis is seen in many joints but in the medial condyle there can be other causes.

Osteochondrosis by definition is a failure of cartilage to ossify during the horses growth period. Typically, it appears by 12 to 24 months of age but can be diagnosed later if no symptoms are present and radiographs of the affected joint have not been performed. Symptoms typically include joint effusion or swelling. Lameness can be present but not always. Medial condyle cysts reliably show more lameness than other joints such as the hock. That said, cystic lesions regardless of affected joint show more lameness than osteochondritis dessicans in which the cartilage surface is disrupted and bone beneath the cartilage is damaged but no bone cyst is seen.

Many researchers have also created bone cysts in the medial femoral condyle by simply lacerating the cartilage with a scalpel blade. Over time, they have seen some of these areas grow into bone cysts such as you have in your horse. The hypothesis is that trauma to the condyle that results in cartilage damage can cause a bone cyst to develop. We think the cyst develops by pressure from the joint fluid pumping up and beneath the damaged cartilage. This is similar to a rock below a waterfall that develops a cavity or dimple in the area where the pressure from the falling water hits the rock. I personally think the “trauma theory” is applicable to other joints where we see bone cysts. If it is osteochondrosis which again is a defect in ossification (bone development) then this should be seen early in life. Your horse is 7 years old and has no arthritic changes. There should be some arthritic change by now if the cystic lesion is a result of osteochondrosis. Therefore, I am going to assume your horse developed the cysts secondary to trauma.

The cause is not so important now. What we need to focus on is treatment. We all as surgeons have seen some of our cases show enlargement of a cyst after surgery. Over the last 20 years we have modified our technique to try and avoid this problem. Nevertheless, we continue to see cystic enlargement post-op on occasion.

I think you have multiple treatment options at this point. (1) Continue to inject both stifles as you have. I would use a corticosteroid such as triamcinolone (Vetalog). I do have cases that do not get the option of surgery that respond favorably to this treatment alone. Adding hyaluronic acid can be helpful but the corticosteroid is most important. If you use this treatment, it is not necessary in my opinion to direct the medication directly into the cyst. A simple medial femoral joint injection has worked well for me. (2) You mentioned Tildren treatment. I have discussed this in another question. Tildren is a biphosphonate similar to medications used for osteoporosis in humans. It reduces the resorption of bone by inhibiting osteoclastic activity. Osteoclasts are bone cells that remove bone. It is not approved in the USA but is approved in Europe for the treatment of navicular disease. Trials are going on now in the USA to get approval here. I have used this drug several times but not enough to confidently substantiate efficacy in medial condylar cystic lesions. Side effects have not been an issue with me. The colic you mentioned is a real issue but if the medication is given reasonably slowly and the horse gets Flunixin (Banamine) prior to infusion, I have had no problem. (3) IRAP injections. This is a treatment where blood is drawn from the horse with medically treated glass beads within the collecting syringe. The blood is then processed and placed in 5 ml syringes. The medical term for this is Interleukin-1 Receptor Antagonist Protein. Once the blood is harvested and the serum is processed, a dose of processed serum is injected into the affected joint. The injections are repeated at 2 week intervals for a series of 3 to 4 treatments. This therapy is used for a wide variety of joint ailments from degenerative arthritis to bone cysts. It has also been used in tendon/ligament injuries. Research has shown it to be a useful therapy and it is gaining in popularity. The science behind IRAP is solid and results have been encouraging. Not all veterinarians are able to offer this. Check with yours and find out if this option interests you. Also it is expensive. (4) Repeat arthroscopy to evaluate the lesions and possibly do further debridement or place a bone graft within the cyst. (5) Finally you might try shock wave therapy to the cystic lesion. This has not been useful in my hands but some claim that it aids in healing. The pro on shock wave is that it can be done standing. The negative is that it could take 4 to 6 treatments which is costly.

Bottom line, do not give up yet. Discuss the above options with your veterinarian. He or she has seen the damage in the joint during surgery and also followed healing via radiographs. As listed above, there are many options still available for your horse. I do not think placing a needle in the cyst on the right caused any harm and may have helped the healing process. Continue with follow-up radiographs and lameness exams and determine a treatment strategy based on the above options. If you can, I would suggest IRAP along with Tildren at this time. Remember, Tildren has little data to support use for your horses problem. IRAP does. If I had to choose one therapy, it would be IRAP at this time or Vetalog into both joints. Hope I have not confused the matter.

This is a good question and I am surprised I have not been asked about this more often this month. I am sure as complicated as founder and laminitis is, there likely could be a monthly Q/A for this topic alone.

There is a surgical option for chronic founder. It is called a deep digital flexor tenectomy. It is commonly done in the standing horse at least with me. In fact, I do not think I have ever anesthetized a horse for this procedure. The procedure requires local anesthesia to the upper limb. A small incision is made on the outside of the limb below the check ligament insertion and the deep digital flexor tendon is isolated. After dissecting the tissue around the tendon, an instrument is inserted and the tendon is severed. Cost of surgery largely depends on where you live. I am in Texas and typically charge $200 per leg plus sedation, farm call, etc. Bandaging is involved post-op as well as stall rest. Special shoeing such as reverse shoes or egg bars are commonly employed in my practice.

All above said, if the horse is comfortable and cycling normally reproductively with corrective shoeing alone, then you can pursue breeding without surgery. If pain and rotation is an issue, then deep flexor tenectomy is a viable option. If you commit to deep flexor tenectomy, be prepared for a broodmare forever. I have had some cases go back to the show ring and win, but I never tell anyone to expect showing to happen.

Success rate is very good in horses with the degree of rotation you have. As in most founder cases, the worse the rotation the more difficult to achieve success. I reliably see a significant increase in sole depth and obvious change in rotation or “derotation” as farriers say. I never hesitate to perform this surgery if more conservative treatments are not working. It is simple to perform, inexpensive, and can be performed standing even in a pregnant mare.

This is a good question on many levels. One, the horse is Arabian. This has perplexed me for years, but we rarely see navicular disease in this breed. I work on many high level competitive Arabians and rarely diagnose navicular disease. I have seen some, but compared to other breeds, it is very disproportionate. Two, the horse was diagnosed with lameness in the right front foot when the reason for exam was stumbling on the left front foot. This is not that unusual with navicular cases as most are lame in both forelimbs. Stumbling is frequently associated with navicular disease. We are beginning to build evidence for the dreaded navicular, but further testing needs to be done before hanging the scarlet “N” around his neck. Your veterinarian did this by way of regional anesthesia (nerve blocks) and radiographs. The horse responded to the block on the right foot, but did it then shift to the left foot? Again, navicular is usually in both feet but can be only in the one foot.

It appears that the treatment and shoeing changes have helped the horse but your original complaint was stumbling on the left front foot. The original problem continues to persist. Because of the horses breed and the persistence of the stumbling, I would look deeper. Again, Arabians are not noted for navicular problems. Have a neurologic exam done to make sure there are no neurologic issues. Consider shortening the toes in front and rockering the toe on the front shoes to encourage breakover. This will shorten the stride, which is not necessarily desired in dressage, but it will aid in the stumbling. Also, you mention the hind feet are shod with longer toes. Remember, with egg bar shoes in front, long toes behind may make the horse prone to over striding with the back feet and possibly pull off a front shoe. Monitor his gait closely.

I think you are on the right track. My concerns are that we do not see much navicular disease in Arabs and the horse continues to stumble. Try a neurologic exam and maybe consider some of the diagnostic tests for EPM, West Nile, or rhinopneumonitis if exam findings support such tests.

One other question for you. This may sound silly, but how deep is the sand in your riding arena? If it is deep, this is a very common cause of stumbling as well as tendon injuries. This said, if footing is an issue, more than one horse should be stumbling.

I will not be much help here. I need to know more specifics regarding the injury. Are the tendons lacerated? Has the fetlock joint been penetrated? Have any bones in the fetlock region been fractured? Any answers you might have would be helpful.

In short, your veterinarian has probably done a thorough examination and performed any diagnostic tests needed to assess the situation. Realy heavily on him or her in regard to treatment vs euthanasia. Believe me, none of us in this profession take euthanasia lightly. If your veterinarian recommends this, it is probably wise. If you are uncomfortable with the recommendation then get a second opinion.

If you pursue treatment then ask about cost, recovery time and prognosis for use in whatever riding discipline you compete.

With all the ringbone discussion this month we should define your particular question. Low ringbone is arthritis of the coffin joint between the short pastern bone and coffin bone. High ringbone is arthritis of the pastern joint between the long and short pastern bones. There is another question similar to this that I have addressed previously. The treatment options for low ringbone are different than high ringbone. Good balanced shoeing, sometimes mimicking that for navicular disease, and coffin joint injections with corticosteroids +/- hyaluronic acid are the mainstay. Bute therapy can be used when needed.

There are reports of cases of low ringbone that have been treated surgically by fusing the coffin joint. This requires going through the bottom of the foot and placing screws across the coffin joint. This commits the horse to broodmare or pasture soundness and has not gained popularity.

If shoeing and the above medical treatments fail, consider neurectomy. This does not treat the condition and only alleviates the pain. Try shoeing him balanced medial to lateral. Consider raising the heel and rockering the toe if the foot is underslung. Try coffin joint injections. Do not forget the injectable and oral supplements available (see previous responses). If all fail, neurectomy surgery is an option. I do not think joint fusion is a good option in horses with low ringbone. You have not scratched the surface yet in regard to treatment options available.

Be patient with the joint injection. I often have to inject this type of case 2 weeks after the initial injection before seeing a positive response. If lameness persists after 2 injections, consider changing the corticosteroid to triamcinalone or adding hyaluronic acid to the injection.

Does the horse have abnormal foot conformation? Is he shod and balanced? If there are issues here, shoeing changes may be in order. Good medial to lateral balance is important and sometimes elevating the heel is of value if he has underslung heels. If the horse has a more club foot conformation this usually means the condition has persisted for over a year and the foot is changing shape in response to the pain. This is similar to what horses with navicular syndrome do. Navicular type shoeing such as raising the heel and rockering the toe can be helpful along with the coffin joint injections. Also consider an injectable medication such as Polyglycan, Legend or Adequan to prolong the interval between joint injections. You may already give oral joint supplements now. These can also be helpful in reducing joint pain and prolonging the joint injection interval.

Neurectomy is certainly an option. You have not exhausted more conservative treatments yet. With failure after only one joint injection, I would not give up and jump to a neurectomy. Try some of the above additional treatments before you send him to the OR. Remember, in order to be a good candidate for neurectomy he (1) must be lame, (2) must go sound after a posterior digital nerve block, and (3) not have any radiographic changes that would jeopardize his future as a show horse.

Outside of this forum I have had some people ask me if they can show a “nerved” horse. Rules are different with all disciplines so always check with your particular discipline before commiting to surgery. You have a dressage horse. FEI rules do allow horses that have been “nerved” to show. So to all who read this, dressage, eventers, jumpers, western, etc., before commiting to neurectomy surgery, make sure your breed or show association allows these horses to perform.

Long term prognosis. Expect 2 to 4 years soundness after surgery at a competitive level. As a pleasure horse they can go 4 to 8 years.

Ringbone has been popular this month. If he is an extreme case, pastern arthrodesis (surgery) may be your only option. Neurectomy, as you have tried, can work on some horses. You typically have to do the surgery high or just below the fetlock joint to provide significant pain relief to the pastern region. Depending on the technique used, regrowth of nerve tissue can occur and therefore sensation returns to the area. If you have not tried pastern joint injections with corticosteroids +/- hyaluronic acid, I would consider this first. Some advanced cases of ringbone are too difficult to inject as the mineralization around the joint makes needle penetration difficult. With surgery, as mentioned in other questions, the long pastern bone and short pastern bone are fused with bone screws or bone plates and screws. This essentially creates one bone and motion ceases in the affected pastern joint. The motion in an arthritic joint that has significant cartilage loss is what causes the pain. Neurectomy does not accomplish fusion, but it does take pain away from the joint if performed high enough to incorporate the pastern region. Eventually, some horses will fuse on their own (ankylosis) and pain and lameness will improve significantly.

Neurectomy and rocker toed shoes are more commonly employed for navicular disease. If he has been treated for navicular disease, pastern arthrodesis is of no value. Have your veterinarian evaluate the horse and take radiographs. He or she will be able to discern if pastern arthrodesis is useful. If there are concerns with the navicular bones, arthrodesis is not a treatment option.

In summary, pastern artrhodesis is an effective remedy to ringbone. Be prepared as it is expensive and requires diligent aftercare. This includes stall confinement, cast monitoring and anywhere from 4 to 12 months to return to work. If this horse is retired, joint injections (if possible), bute treatment, as needed, and patiently waiting for ankylosis may be a more practical option. Obviously, if the horse is in severe pain, surgery may be your treatment of choice. Again, consult your veterinarian and he or she can advise you based on lameness examination and radiographs.

Stem cell or no stem cell. This is the question. Let’s start by acknowledging that stem cell treatment is expensive and invasive to the horse. Therefore, make sure the diagnosis is correct. You did not mention in your question as to whether the horse had an ultrasound exam on the affected limb. This is paramount if you are considering stem cell therapy. We have to know exactly where the lesion is in order to deposit the stem cells appropriately.

Before you consider stem cell treatment, make sure you have accurately localized the lameness. Was swelling present at the sight? Was nerve or joint anesthesia done to localize the lameness? And, again was ultrasound performed?

There is not a tendon that attaches to the bone on the back of the limb in the middle of the cannon bone. You may be referring to a strained inferior check ligament or a bowed tendon. Maybe it is an avulsion fracture at the top of the bone where the suspensory ligament attaches. If this is the case, ultrasound exam is definitely warranted. MRI exam can be done, but depending on where you live, this diagnostic tool may be hard to find.

Since you mentioned stem cell therapy, let’s discuss it. “Stem cell” has become a buzzword in both human and veterinary medicine. We use it more than physicians simply due to political ramifications. In horses, there are different types of stem cell therapy. The two most commonly employed are cells that are harvested from the bone marrow or from adipose (fat) tissue from the buttock region. Do not forget about platelet rich plasma and A-cell, which is not a stem cell but an allograft (substance derived from another species, pig bladder in this case) that are frequently used in tendon injuries. Some utilize shock wave therapy, tendon splitting, etc. In short, there are multiple treatment options out there. It is reported that bone marrow stem cells are superior to adipose stem cells. Platelet rich plasma is reported to heal tendon/ligament injuries equally as well and only requires harvesting blood. Collecting stem cells requires collecting cells from the sternum (bone marrow) or making an incision over the tail head region and collecting fat. Also, as you said, sometimes rest with controlled exercise can adequately heal tendon lesions.

What you need to do is accurately find the source of lameness. This will include regional anesthesia (nerve blocks) and ultrasound if tendon or ligament damage is suspected. If tendon injury is confirmed, then treatment depends somewhat on your pocket book. Rest and physical therapy is cheap. Stem cells are expensive. Stem cell therapy is the rage now and research supports its use. What is the saying, you get what you pay for? I have had success with all of the above therapies. I also have failures with them. Tendon injuries are somewhat unforgiving and recurrence is common. That said, who knows, without nerve blocks you may have foot lameness that shoeing and joint injections may help.

I am trying to visualize this swelling and there is not a typical musculoskeletal injury I can equate with the swelling. I suggest you ultrasound the area and see if there is muscle tissue damage or is it simply edema and swelling confined to the skin. The area (Biceps femoris and semitendinosis) is an area we see a condition called fibrotic myopathy. In simple terms, this is compatible with a pulled hamstring. This condition causes lameness that is most easily recognized at the walk. The horse will have a shortened anterior phase of the stride and firmly land the foot on the ground. It often is referred to as “goose stepping” in reference to the way the Germans marched during WW2. Reliably you can feel a firm or fibrotic muscle in the semitendinosis. Physical exam +/- ultrasound will confirm this if it is present.

To your question regarding picking up the right lead. This typically indicates an issue in the left hind limb as you have. Most commonly it is lower hock joint lameness. What discipline does the horse perform? I am going to suspect western pleasure, reining or cutting.

My advice is to have your veterinarian examine the horse and localize the lameness. If it is in the hock joints then joint injections and joint supplements may be the treatment of choice. If the “hamstring is pulled” then surgical therapy to cut the tendon of insertion of the semitendinosis or shock wave therapy may be in order.

Bottom line, get an accurate diagnosis and then treatment can be advised. I suspect the swelling will go away without therapy but the right lead canter problem may persist. May need hock joint treatment but I cannot say for sure without a good lameness exam. Hock joint lameness reliably will cause problems at the canter. Fibrotic myopathy rarely causes problems at the canter and again is best seen at the walk.

This is a good question to discuss the variety of joint therapies out there. Honestly, I think the equine or veterinary community has more options available than human medicine. The injectable medications (Adequan, Legend, Polyglycan, etc) are more effective than oral supplements. The main reason for this is they do not have to survive digestion. In rats, it has been shown that only 20 percent of the oral supplement survives digestion and makes it into the bloodstream. In horses, most of the studies show clinical benefit with oral supplements in pain or arthritis induced models. Oral supplements have become very popular and there are many on the market to choose from. With their popularity, they have also become more expensive. Sometimes, if you do the math, it is as cheap or cheaper to go with injectable medications twice monthly and get more medication into the joint where it belongs.

To address your question specifically, horses with the lesions you describe do very well. The one that may give some trouble is the plantar P1 fragment in the hind fetlock. It is not usually joint pain from plantar P1 surgery but soft tissue irritation from the surgical approach to remove the fragment. I see more plantar P1 fragments in the hindlimb (as in your horse) and this is typical across the nation. This is good as hindlimb fractures have a better prognosis than forelimb plantar fractures. For those reading who do not understand the terminology, plantar means on the rear or backside of the joint. Dorsal means on the front side of the joint. The dorsal proximal P1 fracture on the front limb should do well and these carry an excellent prognosis. All surgeons have their preferences for post-op management of these cases. I can only tell you what I do but follow the directions of the surgeon as he or she knows best what things looked like in the joint.

I inject the operated joints with hyaluronic acid (Hyvisc, Hylartin, Legend, etc) three weeks after surgery. I will mix a corticosteroid such as triamcinolone in the joint injection if there is pain to flexion or lameness at the 3-week post-op exam. I recommend 30 days stall rest with hand walking 10 to 20 minutes daily followed by small paddock turnout (1/2 acre or less) for an additional 30 days. Two months after surgery the horse should be evaluated to determine if it can go back into light training.

With multiple joints affected on this horse I do think regular joint maintenance will be required. In my practice we have some clients that give the above injectables twice monthly or give it once monthly and a daily oral supplement. I prefer to manage these cases with injectables, as I know a higher concentration of product is getting to the joint where it belongs. If you choose an oral supplement the paste is probably better as you can feel more assured it is being swallowed. How many times do you look in your feed tub and find a powdery residue that is suspiciously the same color as your supplement. Paste or powder is not so much the question. It is how confident are you the horse actually ingested the supplement.

Now for the question re Surpass. A recent study has shown that using Surpass post-op on horses with experimental osteoarthritis model did better than horses given phenylbutazone (bute) alone. I still use phenylbutazone and likely always will post-op. I am not sure when the Surpass was placed over the joint in the study and wonder if it would attract dust and dirt while the sutures are in place. With that said, there is good evidence to support the use of Surpass in chip fracture patients. Since you have already removed sutures I think Surpass can be used any time. I would use it when back in training if the horse were stiff or lame.

Bench knees is a conformational flaw in which the knees are offset to the outside of the limb. It occurs in the forelimbs and is noticeable when viewed from the front. What you see is that the cannon bone is not straight with the upper forelimb and is positioned lateral or outside of the upper limb. The limb can still appear to be straight but simply offset. Often times, pigeon toe or toe in conformation accompanies this conformational flaw.

This is a conformational defect and it cannot be corrected surgically. These horses are more likely to develop splints on the medial (inside) splint bone as the concussion and load is increased. The inside of the limb always carries more of the load, but just more so if the horse is bench kneed. If this is a Quarter horse then you might watch for pigeon toed or toe in conformation as the horse ages. At 14 months you may notice this now but by 18 to 24 months it should be obvious if it is going to develop.

Conformational flaws have been a lively topic of discussion this month. Some can be corrected and some cannot. This is why care and consideration should be taken into your breeding program. I am sure you thought long and hard about what stallion would service your mare. You might have 10 other foals by the same sire that are all perfect. If you know the sire, and he has produced many foals, contact the owner and find out if this conformational flaw is a problem. If it comes from the mare, it is more difficult. She may have 10 to 12 foals in her breeding career while the stallion can have 3 to 4 times that many in one year.

In short, nothing you can do. Enjoy the horse but be ready do deal with medial (inside) splints and other common ailments on the inside of the leg. The horse should be fine. There are worse conformational flaws you could deal with.

This horse is lame based on your comments. If you notice a hip hike at the trot then your concern about showing a lame horse is valid. You likely would be politely excused from the ring. If the injury is truly to the superficial flexor tendon/muscle or the gastrocnemius tendon (Achilles) then this is not caused by hyper-extension but by hyper-flexion. Hyper-extension causes strain to the front part of the limb and most commonly causes a strain or tear in the peroneus tertius. This is a dense ligament that runs from the stifle to the hock and causes the hock and stifle to move in tandem. This is known as the reciprocal apparatus. This is easily diagnosed by flexing the hind limb and with the stifle flexed attempt to extend the hock. If the peroneus tertius is ruptured, you will be able to fully extend the hock while the stifle is flexed. This is not normal. This said, I think the cause of injury may be hyper-flexion. Second, there appears to be an old scar on the tip of the right hock. By the way, your pic’s are excellent. You mentioned some prior drainage from the hock. Was there a traumatic wound that invaded the calcaneal bursa (what is commonly called a capped hock)?

You have waited now for 7 months. The hock is still capped and the horse is still showing lameness at the trot. A good work-up has been done with digital x-rays and ultrasound. My thought would be to ultrasound the bursa again. If fluid is present in the bursa, I would drain it and inject with a corticosteroid if there is no sign of infection. You can also add an antibiotic (most use Amikacin) to your injection to help avoid infection. Granted, the fluid may return, but you have not made much progress in 7 months. Second, I would consider shock wave therapy to the posterior hock region for 3 to 4 treatments 2 weeks apart. Third, have the front portion of the tibia (stifle to hock) evaluated and maybe even ultrasound to evaluate the integrity of the peroneus tertius. If the horse truly had a hyper-extension injury, this is the structure most commonly damaged.

Always remember that something else may be causing the lameness. We all often focus on the previous ailment to find the hock joint to have distal tarsal arthritis or bone spavin.

Re-evaluate the horse and consider the above suggestions. If there is damage to the superficial flexor or gastrocnemius or peroneus tertius, these injuries can take 6 to 12 months to recover depending on severity. Will it get better? I think so. Some of the therapies above may help to hasten the recovery.

The first thing you need to do is to have your veterinarian come out and take radiographs (x-rays) of the affected foot. It might be good to take pictures of both feet for comparison. The concave appearance and “clubby” posture are suggestive that the coffin bone may have rotated. This is easily diagnosed with x-rays. The pictures will also show you if there is persistent infection or white line still within the hoof capsule. Once you have the radiographs you can make a decision on the type of shoeing that would be best. Your veterinarian may also advise medical or surgical therapy again depending on the findings on the radiographs. One thing you did not mention is whether the horse is lame at this time. If no lameness, then shoeing alone will likely do the job. If lame, then your veterinarian can advise on treatment options.
If there is still infection in the foot, another hoof resection would be appropriate and applying a topical medication such as copper sulfate or merthiolate to destroy the offending bacteria or fungus. I know this is hard as you have already endured one regrowth period. If rotation is present, a support shoe such as a heart bar or egg bar would be suggested. Some farriers prefer to use a conventional shoe and fill the back half or the entire sole with a substance such as “Equipak”. The type of shoeing, however, is dictated by findings on radiographs.

So, the first step is to see what is inside the hoof capsule. Once the films are evaluated, an appropriate course of therapy can be prescribed. Also know, if you perform a hoof wall resection, once you are certain the infection is gone, you can fill the defect with acrylic. If no lameness is present, you can ride and compete the horse. The acrylic will grow out with hoof growth so you do not have to wait to grow a new foot.

The surgery for ringbone is called a pastern arthrodesis. This entails placing bone screws or bone plates and screws to fuse the pastern joint. Cost will vary depending on the region of the country you are in. In my practice (Texas) the cost is typically $3,500 for the surgery and you will incur another $1,500 in post-op expenses (board, drugs, cast change, etc.)

Unfortunately it is expensive. Do not forget, you will have 4 to 6 months lay-off if all goes well and maybe longer if there are complications. Also, ringbone can be bilateral meaning both forelimbs or hindlimbs may be affected. This will increase your cost. If both forelimbs are affected and we have a good patient, I try to do both limbs at the same time. Some surgeons elect to do two separate procedures.

Talk to your surgeon and get an estimate.

This is an excellent question. You have done everything right. Your veterinarian started with conservative therapy and gradually got more aggressive with treatments until he or she ultimately cut the medial patellar ligament(s) as a last resort. Do not let this worry you as to whether or not you should have done the surgery. You tried other remedies to no avail. Also, the ligament does heal back together over 3 to 6 months with scar tissue.

Momentary upward fixation of the patella is a condition where the patella (knee cap) cannot disengage from the medial trochlear ridge of the femur. Persistent fixation results in a horse that drags the limb behind them. At a gait faster than the walk, it will carry the limb almost as a flag pole in hyper-extension. You mention two things in your question we should discuss.

One, the horse had a long and difficult recovery from surgery. This is unusual. Generally, these horses are “instantly” fixed and are encouraged to exercise when the suture(s) come out in 10 to 12 days. Sometimes pain medication, such as phenylbutazone (bute), is needed in post-op to alleviate pain but this is a relatively minor standing surgery. In the long term, and why many veterinarians use this procedure as a last resort, is that small chip fractures can develop on the patella that require arthroscopic surgery to alleviate. You had very little choice as conservative therapy did not help much.

Two, you say the horse lifts the leg quite a lot when taking the first step forward. This is not typical of upward fixation but more like a horse with stringhalt. These two conditions are sometimes hard to differentiate. Stringhalt is a condition of the extensor muscles of the hindlimb and causes an exaggerated forward phase of the stride. Some severely affected horses will even hit themselves in the abdomen with the affected hind limb.

Stringhalt is most commonly caused by trauma to the front of the hind limb and severance of the extensor tendon(s). The tendon then scars down to the cannon bone and there is an abnormal hyper-flexion in the hind limb. Singletary pea toxicity has been reported as causing stringhalt and is easily treated by removing the horse from pasture that may have this plant in it. Some cases may have a neurologic component.

All said, your horse should come back from this. You might try injecting the stifle joints again with corticosteroids. Also know, one of the best therapies for momentary upward fixation of the patella is exercise. Make the horse work at the trot, particularly up hills if you have them. This will strengthen the quadriceps and encourage the patella to disengage.

Sounds like this horse has been thoroughly worked up and Tildren therapy has been equivocal. I don’t know if you know how Tildren works. It is a biphosphonate. This class of drug is primarily used for osteoporosis in humans and is approved in Europe in horses for treatment of navicular disease. The goal is to reduce enlargement of the invaginations in the navicular bone by reducing osteoclastic activity. Osteoclasts are cells within bone that cause breakdown of bone. Hence the popularity in human medicine. One treatment you did not mention is coffin joint injection or navicular bursa injection. With the deep flexor tear, using IRAP therapy in the navicular bursa is also an option.

Now to your question regarding neurectomy. If the horse goes sound with a foot block (anesthesia of the palmar digital nerves) then neurectomy is an option. Secondly, there must not be excessive radiographic or MRI change to the flexor surface of the navicular bone. This may be very important in your horse as it has sustained a deep flexor tear. What happens if there is excessive change is that the bone will literally tear through the deep flexor and, if totally severed, could require euthanasia. We typically use neurectomy after all other treatments fail. If this is the case with your horse and it meets the above criteria, then neurectomy is an option. The surgery requires general anesthesia and 3 to 4 weeks recovery time. There are many different surgical techniques and your surgeon can advise you of these. Basically, he or she will use the technique they are comfortable with. The surgery does not cure the condition. It simply permanently alleviates pain in the foot. It is advised to continue to shoe the horse with heel elevation and shorten the breakover to ease stress on the deep flexor tendon.

I perform many of these and have had very good success. It is reasonable to expect 2 to 4 years of performace after surgery. Remember, the above criteria should be met to ensure safety and success.

Neurectomy gets a bad rap sometimes. I see many horses go on and do well after the procedure. I would encourage you to pursue the surgery if all other treatments have failed and it meets the criteria above. I think you will be surprised as to how well the horse does. On the other side, it is difficult to sell a “nerved” horse. Be prepared to be the last owner or if selling, the horse will sell on its merits in the show ring.

Any time screws break means the joint had some motion post-op. This is called cyclic loading and is similar to when you bend a coat hanger until it breaks. Once the first 2 screws broke, it is not surprising that others followed as the joint is becoming more unstable.

This does not mean that the horse cannot heal. It does mean that it will heal with a larger bone callous and will require a longer time to be riding sound. The 2 major things that delay healing, whether in bone or soft tissue, are infection and motion. At this time, it is obvious there is no infection, but I do suspect there is motion in the joint. Until the joint fuses the horse will continue to be lame. To reduce motion now, placing a lower limb fiberglass cast is an option. I do not recommend this at this time as the horse seems reasonably comfortable in the paddock.

I am with you in that I would not ride him until sound at walk and trot. He may have gone “ballistic” from pain. He can be hand walked or ponied at the walk until sound, then pony at the trot. An x- racehorse should remember how to pony.

In short, it will likely take 8 to 10 months from surgery for the horse to be riding sound. Obviously, your barometer will be soundness while working in hand or ponying at the trot. Once that is accomplished, then it is time to mount up.

The type of shoeing largely depends on which tendon was injured. There are 3 structures on the back of the leg. The superficial digital flexor tendon (SDF), the deep digital flexor tendon (DDF) and the suspensory ligament (SL). If the injury is high, it is most likely the SDF or SL.

The only tendon you can really relieve stress from with shoeing is the DDF. A good test you can do is to feel these structures with the horse weight bearing and try to move them side to side. Then place a wedge pad or a ¾ inch block of wood under the heel and again feel the tendons. Then place the block of wood under the toe (or turn the wedge pad around) and again feel the tendons. This mimics the effects of raising or lowering the heel with corrective shoeing.

What you will find is that there is noticeable changes in the DDF, but the SDF and SL are not really changed.

Now, if it is a DDF problem, shoeing with a wedge pad and set the shoe back and extend the heels is appropriate. If it is the SDF or SL (as I suspect) then shoe the horse balanced at the normal angle and set it back off the toe and I would use an egg bar. The egg bar will lend support to the tendons and SL. The key to correct shoeing for this horse is knowing which structure is affected.

This is a difficult question to answer. The amount of exercise largely depends first and foremost on soundness after the surgery. Secondly, it depends on the size of the bone cyst and what was done at surgery. Some surgeons simply debride the bone cyst while others may apply a bone graft or chondral (cartilage) graft at surgery.

If the cyst was debrided and no graft was placed, I would suggest lunging the horse at a trot, 10 minutes each direction 3 to 4 days a week for 2 weeks. If all is well, then go to 20 minutes each direction for 2 weeks or begin riding at the walk and trot for the same amount of time.

All this said, your surgeon will be better to advise you based on X-rays and the horse's soundness at the time of the exam. He or she may wish to inject the joint again. We usually do this if the joint carries excessive fluid or if lameness is present.

These cases can require 6 to 8 months to heal. It is reported than there is only a 60 to 65 percent success rate with medial condylar bone cysts. Success largely depends on the size of the cyst at time of surgery and evaluation of post-op x-rays. I have done every technique from debridement, bone graft, chondral graft, drilling the cyst and conservative management such as joint injections. My experience is that the size of the cyst dictates the prognosis. In other words, the larger the cyst the poorer the prognosis.

Exercise can be useful for recovery from bone cysts so I would encourage you to begin the training I have outlined. That said, always follow the instructions your surgeon gives you after he or she evaluates the horse and takes X-rays.

This is a good question, and in short, there is not a surgical option. I am going to assume that as a foal, the horse had normal forelimb conformation. Particularly as a Quarter horse, they grow and mature, and the chest will widen and push the elbows out. This causes the limbs to rotate inward and create a “pigeon toed” conformation. I suspect the condition originates higher than the knees and is in the elbow or chest region. They usually “paddle” with the feet swinging out in the back phase of the stride and swinging in during the forward phase of the stride.

Many farriers try to correct this by lowering the inside half of the foot and encouraging breakover at the toe to the outside of the foot. If the conformational flaw occurs above the fetlock (ankle) joint, it is difficult for farriers to help with the condition. In fact, trying to correct the flaw can create abnormal stress on the joints and ligaments and can create a situation that predisposes the horse to injury.

I suggest you shoe the horse in a balanced fashion and not get to worried about making him travel straight. Many good horses and Derby winners have conformational flaws in the forelimbs. It usually is best to recognize the flaw, practice good balance shoeing and compete. Trying to change conformational flaws at 4 years of age rarely works and sometimes causes more harm than good.

There is a surgical option for ringbone. Whether to operate depends on the degree of radiographic changes and lameness. If recently diagnosed, and radiographic changes are minimal, you might try injecting the pastern joint with corticosteroids +/- hyaluronic acid.

Surgical treatment has a very good success rate. Surgery is done to arthrodese (fuse) the pastern joint. Basically, you fuse the long pastern bone to the short pastern bone and essentially make it one bone. We use surgery on horses that have significant radiographic change and are not responsive to joint injection.

The procedure is placing bone screws or bone plates and screws across the joint after removing the cartilage in the joint. Some surgeons prefer to also add a bone graft in the joint at the time of surgery. The horse is then placed in a cast for 3 to 6 weeks and stall confined. After cast removal, radiographs are taken to assess healing and fusion. Typically, the horse is allowed paddock turn-out for an additional 60 days and then light exercise can begin. Full training and competition can usually resume 6 to 12 months after surgery depending on the horses discipline.

The risks of surgery are typical of all surgery. Anesthetic complications, infection of the bone implants and cast sores are the most common concerns. With the implants we have today and the casting material, complications are not common. The concern most owners face is the cost of surgery and the down time before you can continue training and showing. The good news is, if you invest in the surgery and be patient, these horses typically can go back to work.