Ask The Vet: Lameness Diagnostic and Treatment - July 09

I am not familiar with this particular joint supplement. As a matter of fact, there are no regulations or agency controlling supplements neither for horses nor humans. Recents studies comparing claimed levels of active molecules to what actually is in the product showed very wide disparity.

As veterinarians advising our clients, our major concern is safety of the product and reliability as far as composition goes. Each veterinarian might have preferences and companies she/he is more comfortable with.

It appears that your veterinarian diagnosed/suspects a stress fracture of the tibia. The location is somewhat unusual as they are more often seen at the back of the tibia.

You are lucky this was caught right away, as these injuries can progress to a complete tibial fracture (if the horse keeps working), which in most cases, result in the need for euthanasia.

I completely agree that he needs complete rest for 12 weeks and repeat radiographs before restarting him.

There is a thin line when dealing with these kind of cases. Corrective shoeing to correct some conformations flaws need to be made early enough before the affected growth plate closes.

The decision to do corrective shoeing/trimming will depend on the severity of the epiphysitis. Your veterinarian, by looking at the radiographs, is the best placed person to make that decision.

You may always ask for a second opinion if you have strong reservations.

You did not mention the age, breed and use of your horse. It seems that she has a bilateral lameness isolated to the digit, worse on the right front. My understanding is that radiographs did not show significant pathology.

I would suspect a lesion of the soft tissue in the foot and pastern region. To try to evaluate her further you can have your veterinarian help with:

- more local anesthesia (blocks) (intra synovial blocks such as coffin joint, navicular bursa and digital flexor tendon sheath blocks) to more accurately localize the source of lameness.

-more imaging: ultrasound, and if you have acces and funds for it, advanced imaging modalities such as Contrast Enhanced Computed Tomography ( CE CT) or Magnetic resonnace imaging (MRI) (usually available at larger referral centers).

If you prefer treating her, therapeutic shoeing (correcting her angles, often raising her heels, shortenning and rolling the toe) and potential coffin joint injections (using steroids) will relieve some horses.

From your description, your horse seems to have severe juvenile arthritis of the lower hock joint.

In such severe cases, inducing fusion of the lower hock joints is indicated (once they are completely fused, the pain stops). There are two major ways to fuse these joints: surgically (by drilling the joints spaces) and chemically (by injecting either ethyl alcohol or mono-iodo-acetate -MIA- in the joint spaces). In most cases, I prefer using the alcohol injection as it is the most economical and least painful process, although it is not an option in some cases that are already partially fused or have communications in between the lower joints and the upper one. Chances of getting fusion and a pain-free horse are fair.

If your horse stumbles a lot and has muscle atrophy, it might be beneficial to have your veterinarian reevaluate him to confirm that no major nerve had been severed in the accident.

Depending on the severity of the initial injury, it might take up to more than a year to return to normal function. Physical therapy, including controlled forced exercise, mobilization, massages and potentially electrostimulation might be very helpful.

I would just plan on using your horse normally and see what happens...

There are not enough cases diagnosed to be able to say that tripartite navicular bones will for sure cause a lameness.

If the lameness is still originating from the hocks (which is likely, but could be verified by your veterinarian by the use of nerve blocks and joint blocks), fusing the lower hock joints using either surgical means (drilling the joints) or chemical means (ethyl alcohol injections or MIA) would definitely be indicated.

Fusing the lower hock joints is an option as these joints are "low motion" joints, and once they are fused, the arthritis pain diseappears. My preference would be to use ethyl alcohol intra-articular injections. Horses treated in this way can continue to work/exercise, and pain relief is often evident within a few weeks, although real fusion is not readily achievable (can take a couple years to happen).

This injection could be repeated after a couple of months if needed. In case it does not work, there is always the option of opting for a surgical treatment.

Deep digital flexor tendon is a really useful procedure in horses worsening laminitis with rotation that is non-responsive to therapeutic shoeing/padding, anti-inflammatories and treatment of the initiating cause.

It is definitely a procedure to consider as it can offer serious relief to some horses. From your description it seems that it would be indicated for your mare. I have seen many horses that lived very comfortably after this had been done.

There are several ways to treat locking patellas including exercise, counter-irritant injections and splitting of the medial patellar ligament.

The desmotomy (cutting the medial patellar ligament) is not a preferred way to treat this condition as, especially when a rest period is not respected post operatively, increased risk of patellar fragmentation.

This said, when all the other techniques have failed, it is definitely the procedure of choice. With a good rest and rehabilitation program to follow, it can be quite safe. Your mare could have a completely normal future athletic career.

Using joints supplements never hurts (as long as they are made by reputable companies, and Nutramax is one of them) and could be helpful for your mare.

The fact that your horse was sound after the shoe was replaced can be explained by a few scenarios: a hot nail (nail that penetrates the sensitive lamina), a shoe too tight (placing abnormal stress on the foot) but also a trimming that is somewhat overdone (and that is frequent).

Your farrier did a great job recognizing and addressing the problem. He checked for hot nails, evaluated the foot and came up with a solution that resolved the problem immediately. You should be happy to have such a skilled farrier working with you.

Tripartite navicular bones are extremely rare. They are often found later on in the life of the horse so they do not necessarily cause lameness or decreased performance. That said, the condition is so rare that making reliable predictions is close to impossible.

I have not heard or had any case that developed Cushing's because of Reserpine.

Several injuries might cause a sudden lameness and heat at the back of the fetlock such as a bowed flexor tendon at the level of the annular ligament of the fetlock, a tear in the suspensory ligament and a few others including a foot abscess.

The structure you see taught on the dorsal aspect of the canon bone is the tensed comon digital extensor tendon. You can cold hose your horse, but importantly, call your veterinarian ASAP.

Severe lameness should receive immediate veterinary attention because of the risk of the injury (already severe judging by the lameness) getting worse, but as importantly because of the risk of laminitis (founder) on the opposite limb (from overload).

Lacerations at the back of the fetlock can involve multiple structures such as the skin and subcutaneous tissue, but also the digital flexor tendon sheath, the flexor tendons and the fetlock joint itself.

Involvement of the skin and subcutaneous tissue rarely warrants that much time off and not such a bad prognosis. If one of the synovial structures (such as the digital flexor tendon sheath or the joint) get involved, the prognosis can somewhat be lowered, although the rest period would not be that long. If the tendons have been cut, even partially, the recovery period would be as long and the prognosis reserved.

All that said, your veterinarian is the one who saw the wound and repaired it. He is the better person to offer recommendations and a prognosis. It all depends on what was involved.

Is your horse lame upon lameness examination on hard ground (especially on circles) by your veterinarian?

If your answer is yes, and the lameness is localized to the foot (by nerve blocks), your pony has some chronic foot pain (potentially navicular syndrome) and might benefit, added to the corrective shoeing, of some coffin joint injections.

Ideally, advanced imaging such as Contrast Enhanced Computed Tomography (CE CT) or Magnetic Resonance Imaging (MRI) could be performed to gain information on what exactly is going on and allow for the best possible treatment.

If your pony is not lame, a neurological examination would be indicated as the tripping might be a sign of propriocetive deficit. If this is confirmed, your veterinarian will discuss further testing.

Blocking a nerve means injecting a local anesthetic around a nerve. Nerving a horse is a surgical procedure during which the nerve supply to the foot is cut. Usually this procedure is reserved to cases of chronic foot pain (i.e. navicular syndrome) that does not respond to therapeutic shoeing and potential coffin joint or navicular bursa injections.

Nowadays, when finances allow it, further diagnostics are performed such as Contrast Enhanced Computed Tomography (CECT) or Magnetic resonance imaging (MRI) to evaluate the soft tissue structures of the foot and potentially treat them. The procedure is safe in most cases, and for the appropriate cases, allows soundness and use for several years.

There are always risks of fatal complication such as a Deep digital flexor tendon rupture, navicular bone fracture, or osteomyelitis, although those are relatively uncommon. Other complications include neuroma formation (painful nerve proliferation at the cut nerve end) and nerve regrowth (in some cases happens within a year, but in most cases it takes several years to happen).

What you need to be very careful with is having him shod with a pad to prevent injury to his sole (bottom of the foot), and to check his foot everyday for potential foreign body penetration (i.e. nails) as the horse will not feel it.

Overall, buying a nerved horse is not advisable.

if your mare is staying sound and her feet have improved so much over the years, you are certainly doing the right thing. Quarter cracks can be very challenging and require consistent monitoring and careful trimming and shoeing. In some cases, we get the cracks patched too or wired. Your mare, having dealt with this for so long and staying sound, tells me that you and your farrier are doing a great job.

Your horse might be neurologic. For your safety, you need to stop riding her immediately and have a veterinarian evaluate her.

The swelling you are seeing could be either due to excess fluid in the fetlock joint or in the tendon sheath. This is a sign of inflammation in either one of these structures.

Because there is a lameness associated, I would recommend having your veterinarian examine the area using nerve and synovial anesthesia techniques (when the veterinarian numb a structure or a part of the leg and then evaluates the horse to see if the lameness has improved). This will identify what area of the limb is the source of the lameness.

Once this is done, he/she will be able to take either radiographs or ultrasound the particular area and most likely come out with a diagnosis and will give you treatment options.

The rehabilitation programs with stall rest and progressively increasing hand-walking and trotting are superior to pasture turn out in most cases.

Additionnaly, intra-lesionnal injections with biologicals that are thought to enhance healing such as PRP (platelet rich plasma) or stem cells rich products (bone marrow concentrate, fat derived nucleated cell portion, cultured stem cells, etc.) are currently being widely used clinically.

The effects of such injections is under investigations by multiple research groups both on the human and the veterinary sides. Large blinded clinical studies are still lacking, although results obtained in laboratory and small clinical studies are promising. Our clinical impressions are very encouraging.

Upward fixation of the patella (locking stifle) is not an uncommon problem, especially in horses that have been layed off for awhile or have recently lost some weight. It does not usually show any radiographic changes, and does not usually respond to anti-inflammatories such as phenylbutazone (it is more of a mechanical gait abnormality than a pain driven lameness). Realistically, the stifle could be a cause of lameness in your horse, but much more than in any other hind limb lame horse.

Statistically, his hocks are more likely to be the problem, but what you should do is to have your veterinarian come and examine him and perform a lameness evaluation. This might involve watching him move but also flexion tests (when the veterinarian flexes different joints of a horse stressing the particular joint and then watches him move out to help locate the problem), nerve blocks (local anesthesia to numb various parts of the limb of the horse in a systematic fashion, usually from the lower part of the leg moving upward until the lameness stops) and intraarticular blocks to locate the source of the lameness. When an area is located, diagnostic imaging will be performed (X-rays or ultrasonography).

To answer your question about stifle issues' diagnosis, the best way is to combine the veterinarian physical examination, lameness evaluation and local anesthesia (intraarticular anesthesia).

If your horse goes sound after the intraarticular anesthesia, you know for sure the problem is there. After this diagnosis, radiographs and ultrasound, as complementary techniques, will give you the best non-invasive diagnostic set. In select cases where the lameness responds to an intraarticular anesthesia and no problems are found on either X-rays or Ultrasound, diagnostic arthroscopy (surgery done under general anesthesia during which the surgeon introduces through a very small incision a small camera) might be needed.

Most common problems seen in the stifle include upward fixation of the patella (locking stifles), but also OCD lesions (developmental disease more common in youg horses), subchondral bone cyst, meniscal injury and collateral ligament injuries.

From your question, it seems that your mare is having several problems on several limbs(front feet, to hock injections to suspensory...), especially if she has not been worked hard. Have all the attempted treatments and all the suspicions been based on nerve blocks?

If that is not the case, you should go back to the drawing board and have nerve blocks performed to truly localize the origin of the lameness. Once that is done, your veterinarian will be able to offer you the best fitted options for either further diagnostics or treatments.

Ideally, you can have your veterinarian perform nerve blocks (where we anesthetize various parts of the limb in a systematic fashion from the ground up) to definitively localize the source of the lameness. This procedure is not always easy to do in the field as it is time consuming, and might need to be done at a referral hospital.

Alternatively, because roping horses often get stifle and pastern issues, those two areas could be radiographed for a start.

From my understanding, your horse is lame on a hindlimb and back sore. I am not sure how much the initial shoeing has to do with the current lameness, but it is always a possibility. The fact that he did not respond to hock and stifle injection might be indicative of a problem elsewhere. I would recommend having your veterinarian either perform nerve blocks to localize the source of the lameness or refer you to a referral hospital to have this done.

Once the lameness source has been identified, more would be done to image it (eg. X-rays, Ultrasound, etc.), and come up with a plan to treat or manage it.

If your veterinarian can see your horse lame at the trot on a straight line, he is right grading his lameness 3/5.

What I would recommend, with no hesitation, is to have your veterinarian perform nerve blocks and localise the lameness.

Due to the breed and age of your horse, it is likely in the foot, but the nerve blocks will definitely justify investing money in imaging (of the foot or whatever region the lameness is localised to).

Buying a horse is always a gamble. It is important in your situation to try to collect as much information about the horse as possible, especially his work history (has he had to be layed up from work, etc.).

You can also request, from the current owner, a copy of his medical records to be released to you.

It is good that you have the opportunity to keep the horse for a period of time and use him. If there is any doubt you can ask for that period to be extended.

The most important step is to have, like you have planned, a complete pre-purchase examination performed by your veterinarian. Inform your veterinarian of your concerns before the prepurchase examination.

This will obviously include a lameness evaluation on both hard and soft ground, straight lines and circles and including flexion tests. Potentially, radiographs and also blood collection for drug testing (either to test or to hold, particularly to try to detect traces of drugs from joint injections) may also be performed during this procedure.

A pre-purchase examination will give you much information, and in most cases, will detect an eventual problem. Nonetheless, a pre-purchase examination only reflects the status of the horse on that particular day, and in some cases (relatively rare) something could be missed.

Ultimately, it is your decision to proceed or not with the purchase. Having your veterinarian's report will help you make that decision. If you are not comfortable and suspect foul play, you could keep the horse for another three to four weeks after the purchase examination and have the vet take another look at him before making a final decision.

Navicular disease refers to a group of symptoms associated with foot pain in horses. With the advances of equine imaging abilities (especially Contrast Enhanced Computed Tomography -CECT- and Magnetic Resonance Imaging -MRI) the veterinary community has come to learn that there are many different causes for foot pain in horses and many different "navicular disease".

For your horse, I would recommend to have your veterinarian come and examine him. He/she will probably do a physical examination, then watch him move (usually in a straight line, but also on a lunge line, preferably on a harder surface), and if your horse is showing any evidence of lameness, he will discuss with you the need of confirming that the feet are the source of the lameness. This is done by applying hoof testers and performing a nerve block. If your horse has indeed some foot pain, he will proceed with imaging modalities such as radiographs and potentially ultrasound, which is most common. Also when available, affordable and needed, advanced imaging techniques such as CECT and MRI provide a plethora of information that are extremely helpful for the formulation of a treatment plan.

If your horse is not lame but you are still concerned, radiographs might still be helpful to gain information and potentially get some additional guidance for shoeing.

This is going to be pretty challenging, I understand your veterinarian's reserves.

The concerns with applying casts to foals that young include the possibility (almost certainty) of getting cast sores, but also the risk if the baby favors the leg to end up with some angular deformation of the "healthy leg". Finally, ligament and tendon laxity can also become a problem (the tendons and ligament that are shielded from stresses end up getting looser and weaker).

Realistically, I agree with your veterinarian's plan.

If the fetlock is truly luxated, and the bones are not mishaped, I believe that casting for a very short period and following up with splints and ideally articulated splints might give you a good chance to get him back.