Navicular Syndrome Diagnosis
Late Stage Navicular Syndrome Diagnosis is Typical
Navicular Syndrome Diagnosis in Horses is made by an equine veterinarian. Although a horse can have Navicular Syndrome in hind feet, usually a horse presents with lameness in a front hoof or both front feet which has become chronic hoof pain for the horse, and which came on gradually. Generally, Navicular Syndrome is not an accute lameness of the hoof of a horse, but rather Navicular Syndrome pain developed over time and the owner may not notice early Navicular Sydrome Symptoms for diagnosis since the pain tends to present with work and self-resolve with rest in the early stages of Navicular Syndrome.
Navicular Syndrome Diagnosis is therefore oftem made after the horse has suffered quietly for many weeks, months, or in some cases, even years. When Navicular Syndrome has been left untreated for a long time, the damage to the horse's hoof may be significant and even irreversable. This is why early Navicular Syndrome Diagnosis is important and knowing the Navicular Sydrome Symptoms is critical for horse owners to diagnose Navicular Syndrome.
Navicular Syndrome Diagnosis - Visual Examination of Standing Horse
The first step to diagnose Navicular Syndrome is to observe how the horse stands. While "pointing" a hoof is one common indicator of most hoof lameness in a horse, a horse with Navicular Syndrome may stand with the painful hoof curled in order to release as much pressure from the Navicular Fulcrum as possible. By curling the hoof under (see diagram below) the horse removes all pressure from the DDFT on the Navicular area. This is the point of pain in Navicular Syndrome.
If the horse will not stand still (dances) or sways back and forth, shifting weight from one hoof to the other and seems stressed, perhaps the horse may even do tail swishing for no apparent reason, the probable diagnosis will be Navicular Syndrome in both feet, either fore or hind. The behavior of the horse afficted with Navicular Syndrome in both feet in front or back is due to the horse not being able to find any comfortable way to stand.
Navicular Syndrome Diagnosis - Visual Examination of Horse Hoof
The second step to diagnose Navicular Syndrome is to look at the hoof, and using no special tools, note if any of the common attributes of Navicular Syndrome are present to include in your diagnosis. One of the most commonly overlooked indicators for Navicular Syndrom diagnosis is a hoof with any WHITE ( non-pigmented area ) in the SHELL of the hoof. This can be a "streak" or an all-white hoof shell.
Angle of Horse Hoof in Navicular Syndrome Diagnosis
The first observation in Navicular Syndrome Diagnosis is the angle of the hoof, or more correctly, how much heel is present versus how much toe. For a horse with very short heels (or with the hairy bulbs nearly or actually touching the ground) or with a very long toe, it is not a question of "if" it will develop Navicular Syndrome pain, but a question of "when" it will be diagnosed with Navicular Syndrome.
In almost all diagnosed cases of Mechanical Navicular Syndrome (as differentiated from Navicular Disease which indicates pathology, Mechanical Navicular Syndrome is caused by force & pressure acting on the navicular area) a long toe and/or a low heel was not only present, but a contributing factor, if not "the" cuprit" which led to a Navicular Syndrome diagnosis.
The primary cause of the pain in Mechanical Navicular Syndrome is from the abnormally high pressure on the Navicular area from the Deep Digital Flexor Tendon (DDFT) when the horse's hoof heel is too low, or the horse's hoof toe is too long and causes delay in breakover; resulting in increased pressure on the Navicular Bone before breakover and even when the horse is standing. The Navicular Fulcrum is the pressure point from the Deep Digital Flexor Tendon (DDFT) where it contacts the Navicular Bursa and bends over the Navicular Bone.
Generally, Navicular Syndrome can be diagnosed when the lameness seems to dissappear after resting after work because the intense pain in the horse's hoof from the high pressure during forced breakover at speed and bearling the load of a rider during work is gone during rest.
Sole & Frog of Horse Hoof in Navicular Syndrome Diagnosis
The second observation in Navicular Syndrome diagnosis is the sole and frog.
If the sole and frog have been pared with a hoof knife and the frog appears dried and shrivelled (wrinkled & contracted) it is an indication that the frog of the horse's hoof is not being stimulated with contact from the ground. Alternatively, if the frog is touching the ground or has less than 1/8" ( one eigth of an inch ) clearance, there may be continual pressure on the horse's frog which will be translated directly to the Navicular area which is directly above it.
The ground clearance of the frog should be no more than one half an inch, and no less than one quarter inch. This allows for no continuous pressure on the frog (and thus no pressure on the Navicular area) while the horse is standing on a hard surface, for instance, a stall, trailer, hard-packed paddock, etc. - but the frog will touch the ground and be stimulated when the horse takes steps and the hoof expands, or when the horse is on soft ground.
Navicular Syndrome Diagnosis - Testing of Hoof for Navicular Syndrome Pain Response
Use of THUMB in Navicular Syndrome Diagnosis
If Navicular Syndrome symptoms are severe, probable diagnosis of Late Stage Navicular Syndrome is easy and requires no special tools. Verify isolation of the pain of Navicular Syndrome by pressing your thumb between the bulbs of the horse's hoof heel as shown in the diagram below with the red line.
Begin applying pressure GENTLY at the top of the area indicated by the red line in the horse hoof image above. If the horse tries to move his foot to escape the pain, there is high probability of STAGE 4 Navicular Syndrome symptoms diagnosis. If the horse ignores the pressure, slowly apply as much pressure as possible with just your thumb until either the horse responds or you can't press any harder. If you get any reponse from just the pressure from your thumb, the horse has pain there. If you do not get a pain response, move further down the red line and begin applying pressure with thumb in a new area.
If you get no pain response from the horse using your thumb on the Navicular area between the bulbs of the horse's heel, move to testing the sole and frog with thumb, and then with caliper hoof testers if no pain response.CAUTION: Keep your head and face well away from the horse's hoof when applying a pain response pressure test for Navicular Syndrome and increase pressure gradually to each new area, starting with "barely touching". Alternatively, if the test is positive, the horse's foot may come off the ground LIKE A ROCKET and injure you. The horse may totally ignore hard pressure in one area and respond suddenly to even light pressure in an area just a half inch away.
Next, pick up the horse's foot and apply pressure to the frog with your thumb. If the horse tries to pull his foot away from you, there is a pain response from the Navicular area and Navicular Syndrome diagnosis is probable. If there is no pain response from just the pressure of your thumb, use caliper hoof testers on the horse's frog.
image Navicular Syndrome Diagnosis - Pressure Testing for Navicular Syndrome on horse hoof frog with thumb and caliper hoof testers.
Before using caliper hoof testers on the horse's frog, you are advised to first use your thumb. The thumb offers a more gentle pressure, and if the horse responds to pressure from your thumb, using the caliper hoof testers will certainly cause undue pain and upset the horse quite a bit and the horse may be in pain for quite some time afterward and be unco-operative.
Navicular Syndrome Diagnosis - Veterinarian Testing for Navicular Syndrome
Veterinarians have other tools for diagnosing Navicular Syndrome in horses
The Navicular Syndrome diagnosis tests above can be done by any horse owner and give good cause for a call to a veterinarian to ensure they cannot find another reason for the pain. This is critical because there may be other things that are the cause.
Navicular Syndrome Diagnosis Tool #1 - Low Palmar Digital Nerve Block
Palmar Digital Nerve is associated with the navicular area, and a Low Palmar Digital Nerve Block employs an injection of anesthetic to numb the area. This is an easy and inexpensive test. If after the application of anesthetics to the horse goes sound and/or no longer responds to pressure with a pain response, the pain is isolated to the Navicular Area and Coffin Bone. This may mean that there is a problem with the coffin bone or surrounding tissue, so other testing is advised, however if the horse continues to be unsound or responds to pressure, the diagnosis of Navicular Syndrome alone may not be sufficient.
Navicular Syndrome Diagnosis Tool #2 - Diagnostic Imaging - Radiograph / X-Ray / Thermal / MRI
Radiographs (X-Rays) Thermal and Magnetic Resonance Imaging of the foot are expensive but can tell you what the problem is not (can rule-out fracture, for instance) or help discover what the problem is if (proper) treatment for Navicular Syndrome has not been successful.
image Navicular Syndrome Diagnosis - Tools - Thermal Imaging and Magnetic Resonance Imaging MRI
Many equine veterinarians carry a portable Thermal Imaging Camera. It is most useful to derminine where swelling (heat) is occurring in the limb ( how far up the leg the abnormal heat pattern goes ) especially when the condition is affecting only one foot so that the heat maps of the two feet can be compared.
Magnetic Resonance Imaging (M.R.I.) machines are large and expensive and generally only large vet clinics and universities have one for large animals such as horses. Of all three imaging tests, it is usually the most expensive, but can give important insight into soft tissue damage in the late stages of Navicular Syndrome.
image Navicular Syndrome Diagnosis - Tools - Xray Radiograph of Horse Hoof with Navicular Syndrome showing cause of pain is Low Heel
The high quality X-Ray / Radiograph above of the horse hoof shows a clear indicator of Navicular Syndrome which would be noticed with the eye and no special equipement.
Generally, if Navicular Syndrome is suspected, because it does no harm and usually resolves the problem (since the problem is usually Navicular Syndrome ) simply beginning Navicular Syndrome Treatment is the fastest, easiest and cheapest thing to do, and is THE MOST SENSIBLE since it is the only action that can bring about a RESULT.
Many owners spend THOUSANDS on testing ( when considering the time lost from work, miles travelled, accommodations, vet referral fees, actual testing fees, etc. ) and still have no SOLUTION...or even a definitive diagnosis. Vets today prefer to say "Caudal Heel Pain" or "Caudal Heel Syndrome" - which is just fancy vet talk for "Now you can't sue mem but you still owe me for my time".
When Navicular Syndrome Diagnosis is suspected, save yourself hundreds of dollars and save your horse a lot of pain with...