What is hip dysplasia?
To understand hip dysplasia we must have a basic understanding of the joint that is being affected. The hip joint forms the attachment of the hind leg to the body and is a ball and socket joint. The ball portion is the head of the femur while the socket (acetabulum) is located on the pelvis. In a normal joint the ball rotates freely within the socket. To facilitate movement the bones are shaped to perfectly match each other; with the socket surrounding the ball. To strengthen the joint, the two bones are held together by a strong ligament. The ligament attaches the femoral head directly to the acetabulum. Also, the joint capsule, which is a very strong band of connective tissue, encircles the two bones adding further stability. The area where the bones actually touch each other is called the articular surface. It is perfectly smooth and cushioned with a layer of spongy cartilage. In addition, the joint contains a highly viscous fluid that lubricates the articular surfaces. In a dog with normal hips, all of these factors work together to cause the joint to function smoothly and with stability.
Hip dysplasia is associated with abnormal joint structure and a laxity of the muscles, connective tissue, and ligaments that would normally support the joint. As joint laxity develops, the articular surfaces of the two bones lose contact with each other. This separation of the two bones within the joint is called a subluxation, and this causes a drastic change in the size and shape of the articular surfaces. Most dysplastic dogs are born with normal hips but due to their genetic make-up (and possibly other factors) the soft tissues that surround the joint develop abnormally causing the subluxation. It is this subluxation and the remodeling of the hip that leads to the symptoms we associate with this disease. Hip dysplasia may or may not be bilateral; affecting both the right and/or left hip.
What are the symptoms of hip dysplasia?
Dogs of all ages are subject to hip dysplasia and the resultant osteoarthritis. In severe cases, puppies as young as five months will begin to show pain and discomfort during and after exercise. The condition will worsen until even normal daily activities are painful. Without intervention, these dogs may eventually be unable to walk. In most cases, however, the symptoms do not begin to show until the middle or later years in the dog's life.
The symptoms are similar to those seen with other causes of arthritis in the hip. Dogs often walk or run with an altered gait. They may resist movements that require full extension or flexion of the rear legs. Many times, they run with a 'bunny hopping' gait. They will show stiffness and pain in the rear legs after exercise or first thing in the morning. They may also have difficulty climbing stairs. In milder cases dogs will warm-up out of the stiffness with movement and exercise. Some dogs will limp and many will become less willing to participate in normal daily activities. Many owners attribute the changes to normal aging but after treatment is initiated, they are surprised to see a more normal and pain-free gait return. As the condition progresses, most dogs will lose muscle tone and may even need assistance in getting up.
Who gets hip dysplasia?
Hip dysplasia can be found in dogs, cats, and humans, but for this article we are concentrating only on dogs. In dogs, it is primarily a disease of large and giant breeds. German Shepherds, Labrador Retrievers, Rottweilers, Great Danes, Golden Retrievers, and Saint Bernards appear to have a higher incidence, however, these are all very popular breeds and may be over represented because of their popularity. On the other hand, sighthounds such as the Greyhound or the Borzoi have a very low incidence of the disease. This disease can occur in medium-sized breeds and rarely in small breeds. It is primarily a disease of purebreds although it can happen in mixed breeds, particularly if it is a cross of two dogs that are prone to developing the disease.
What are the risk factors for the development of hip dysplasia?
Hip dysplasia is caused by a subluxation in the hip joint. This creates abnormal wear and erosion of the joint and as a result arthritis and pain develop. The disease process is fairly straightforward; the controversy starts when we try to determine what predisposes animals to contracting the disease.
Genetics: Researchers agree that hip dysplasia is a genetic disease. If a parent has hip dysplasia, then the animal's offspring are at greater risk for developing hip dysplasia. If there are no carriers of hip dysplasia in a dog's lineage, then it is highly unlikely he will not contract the disease. If there are genetic carriers, then he may contract the disease. We can greatly reduce the incidence of hip dysplasia through selective breeding. We can also increase the incidence through selectively breeding. We cannot, however, completely reproduce the disease through selective breeding. In other words, if you breed two dysplastic dogs, the offspring are much more likely to develop the disease but the offspring will not all have the same level of symptoms or even necessarily show any symptoms. The offspring from these dogs will, however, be carriers and the disease will most likely show up in their offspring in later generations. This is why it can be challenging to eradicate the disease from a breed or specific breeding line.
Nutrition: It appears that the amount of calories a dog consumes and when in the dog's life those calories are consumed have the biggest impact on whether or not a dog genetically prone to hip dysplasia will develop the disease.
Experimentally, it has been shown that obesity can increase the severity of the disease in genetically susceptible animals. It stands to reason that carrying around extra weight will exacerbate the degeneration of the joints in a dog; including the hip. Dogs that may have been born genetically prone to hip dysplasia and are overweight are therefore at a much higher risk of developing hip dysplasia and eventually osteoarthritis.
Another factor that may increase the incidence of hip dysplasia is rapid growth in puppies during the ages from three to ten months. Experimentally, the incidence has been increased in genetically susceptible dogs when they are given free choice food. In one study, Labrador Retriever puppies fed free choice for three years had a much higher incidence of hip dysplasia than their littermates who were fed the same diet but in an amount that was 25% less than that fed to the free-choice group.
Feeding a diet that has too much or too little calcium or other minerals can also have a detrimental effect on the development of the hip joint. However, with today's complete and balanced dog foods this has become a rare occurrence. The practice of feeding home-made dog foods is popular with some dog owners. These diets must be carefully monitored for proper nutritional balance; not only for calcium and the other essential minerals but for all nutrients.
Exercise: Exercise may be another risk factor. It appears that dogs that are genetically susceptible to the disease may have an increased incidence of disease if they over-exercised at a young age. But at the same time, we know that dogs with large and prominent leg muscle mass are less likely to contract the disease than dogs with small muscle mass. So, exercising and maintaining good muscle mass may actually decrease the incidence of the disease. Moderate exercise that strengthens the gluteal muscles, such as running and swimming, is probably a good idea. Whereas, activities that apply a lot of force to the joint are contraindicated. An example would be jumping activities such as playing Frisbee.
How is hip dysplasia diagnosed?
The diagnosis of canine hip dysplasia is typically made by combining: clinical signs of arthritis and pain, a complete physical exam, and radiographs (x-rays). If a dog is showing outward signs of arthritis, there are usually easily recognized changes in the joint that can be seen on radiographs. In addition, the veterinarian may even be able to feel looseness in the joint or may be able to elicit pain through extension and flexion of the rear leg. Regardless, the results are straightforward and usually not difficult to interpret.
However, about half of the animals that come in for a determination on the health of their hip joints are not showing physical signs, but are intended to be used for breeding. The breeder wants to ensure that the animal is not at great risk for transmitting the disease to his or her offspring. There are two different testing methods that can be performed. The traditional is OFA testing. The other relatively newer technique is the PennHip method.
OFA: The method used by the Orthopedic Foundation for Animals (OFA) has been the standard for many years. The OFA was established in 1966, and has become the world's largest all-breed registry. The OFA maintains a database of hip evaluations for hundreds of thousands of dogs. Radiographs are taken by a local veterinarian using specific guidelines and are then submitted to the OFA for evaluation and certification of the dog's hip status. Since the accuracy of radiological diagnosis of hip dysplasia using the OFA technique increases after 24 months of age, the OFA requires that the dog be at least two years of age at the time the radiographs are taken. Because some female dogs experience additional hip subluxation when they are in heat, pregnant or nursing the OFA recommends that the evaluation should not be performed during these times.
To get the correct presentation and ensure that the muscles are relaxed, the OFA recommends that the dog be anesthetized for the radiographs. OFA radiologists evaluate the hip joints for congruity, subluxation, the condition of the acetabulum, and the size, shape, and architecture of the femoral head and femoral neck. The radiographs are reviewed by three radiologists and a consensus score is assigned based on the animal's hip conformation relative to other individuals of the same breed and age. The OFA then places the evaluated dogs into one of seven categories. Normal hips are graded as: excellent, good or fair. If the consensus is unclear the dog is graded as borderline dysplastic. And dogs with obvious radiographic signs of hip dysplasia are graded as: mild, moderate, severely dysplastic. Dogs with hips scored as borderline or dysplastic (mild, moderate, severe) are not eligible to receive OFA breeding numbers.
The OFA will also provide preliminary evaluations (performed by one OFA radiologist) of dogs younger than 24 months of age to help breeders choose breeding stock. Reliability of the preliminary evaluation is between 70 and 100% depending on the breed.
PennHIP: The diagnostic method used by the University of Pennsylvania Hip Improvement Program (PennHIP) uses unique radiographic views of the dog's hips to more accurately identify and quantify joint laxity. This program was conceived in 1983 and became a usable system by 1993. To assure quality and repeatability among diagnostic centers using the PennHIP technique, veterinarians must take a special training course to become certified. Radiographs of the hips are taken with the dog under heavy sedation. These radiographs can be taken on a dog as young as 16 weeks. Two views are obtained with the hind limbs in neutral position to maximize joint laxity. These are known as the distraction and compression radiographic views. Weights and an external device are used to help push the head of the femur further into or away from the acetabulum. The amount of femoral head displacement (joint laxity) is quantified using a distraction index or DI. The DI ranges from 0 to 1 and is calculated by measuring the distance the center of the femoral head moves laterally from the center of the acetabulum and dividing it by the radius of the femoral head. A DI of 0 indicates a very tight joint. A DI of 1 indicates complete luxation with little or no coverage of the femoral head. A hip with a distraction index of 0.6 is 60% luxated and is twice as lax as a hip with a DI of 0.3. A third radiographic view is taken using the same positioning as the OFA. The "hip-extended" view is used to obtain additional information regarding the possible presence of degenerative joint disease (DJD) in the hip.
When the PennHIP DI was compared to the OFA scores for 65 dogs, all dogs scored as mildly, moderately, or severely dysplastic by the OFA method had a DI above 0.3.
Hip laxity as measured by the DI is strongly correlated with the future development of osteoarthritis. Hips with a DI below 0.3 rarely develop osteoarthritis. Although hips with a DI above 0.3 are considered "degenerative joint disease susceptible," not all hips with a DI greater than 0.3 will develop osteoarthritis. It is known that some hips with radiographically apparent laxity do not develop osteoarthritis. A means of differentiating lax hips that develop osteoarthritis from those that will not is important in developing a prognosis and making treatment or breeding recommendations. In one study, the DI obtained from dogs at four months of age was a good predictor of later osteoarthritis, though the 6 and 12-month indices were more accurate.
The PennHIP method has gained popularity and more and more veterinarians are becoming certified.
How is hip dysplasia treated surgically?
There are several surgical procedures available to treat hip dysplasia depending on the dog's age, body size, and the severity of the hip joint's degeneration.
Triple Pelvic Osteotomy (TPO): TPO is a procedure used in young dogs usually less than 10 months of age that have radiographs that show severe hip laxity, but have not developed damage to the joints. The procedure involves surgically breaking the pelvic bones and realigning the femoral head and acetabulum restoring the weight-bearing surface area and correcting femoral head subluxation. This is a major surgery and is expensive, but the surgery has been very successful on animals that meet the requirements.
Juvenile Pubic Symphysiodesis: A less invasive surgery for treating hip dysplasia is called Juvenile Pubic Symphysiodesis. This surgery prematurely fuses two pelvic bones together, allowing the other pelvic bones to develop normally. This changes the angle of the hips and improves the articulation of this joint, lessening the likelihood of osteoarthritis. Early diagnosis is critical, since the procedure must be done before 20 weeks of age, preferably 16 weeks, and before any signs of arthritis are evident.
Total Hip Replacement: This may be the best surgical option for dogs that have degenerative joint disease as a result of chronic hip dysplasia. Total hip replacement is a procedure that can produce a functionally normal joint, eliminate degenerative changes, and alleviate joint pain. The procedure involves the removal of the existing joint and replacing it with an artificial joint or prosthesis. To be a candidate for this procedure, the animal must be skeletally mature. With the new micro-prosthetics there is no minimum size limit. In addition, there is no maximum size limit. If both hips need to be replaced, there is a three-month period of rest recommended between the surgeries. As with the TPO surgery, this is an expensive procedure but it produces very good results. Most dogs return to a near normal level of activity without pain.
Femoral Head and Neck Excision: Femoral head and neck excision is a procedure in which the head of the femur is surgically removed and a fibrous pseudo-joint replaces the hip. This procedure is considered a salvage procedure and is used in cases where degenerative joint disease has occurred and total hip replacement is not feasible or if the expense of a total hip replacement is prohibitive. The resulting pseudo-joint will, in most cases, be free from pain and allow the animal to increase his activity, however, full range of motion and joint stability are decreased. For best results, the patient should weigh less than 40 pounds; however, the procedure may be performed on larger dogs.
How is hip dysplasia treated medically?
|Helping a dog maintain his recommended weight may be the single most important thing an owner can do for their pet.|
Medical management of hip dysplasia and osteoarthritis has greatly improved thanks to the introduction and approval of several new drugs. Because hip dysplasia is primarily an inherited condition, there are no products on the market that prevent its development. Through proper diet, exercise, supplements, anti-inflammatories, and pain relief, you may be able to decrease the progression of degenerative joint disease, but the looseness in the joint or bony changes will not change significantly.
Because of the high cost involved with corrective surgeries, medical management is many times the only realistic option for pet owners. Medical management is multifaceted. For the best results, several of the following modalities should be instituted.
Weight Management: Helping a dog maintain his recommended weight may be the single most important thing owner scan do for their pets. Surgical procedures and medical therapies will be far more successful if the animal is not overweight. You, as the owner, have control over what your dog eats. If you feed a quality food in an amount appropriate for your dog's size, breed and activity level and keep treats to a minimum, your dog should be able to maintain an ideal weight. Considering that more than half of the pets in the U.S. are overweight, there is a fair chance that many of the dogs with hip dysplasia/osteoarthritis are also overweight. If your dog is overweight, seek the advice of your veterinarian concerning a lower calorie dog food and an exercise program.
Exercise: Exercise is equally important in losing and/or maintaining the appropriate weight. Exercise that provides good range of motion and muscle building as well as limiting wear and tear on the joints is best. Leash walks, swimming, walking on treadmills, and slow jogging are excellent low-impact exercises. Bear in mind that an exercise program needs to be individualized for each dog based on the severity of the osteoarthritis, his weight, age, and physical condition. In general, too little exercise can be more detrimental than too much, however the wrong type of exercise can actually cause harm. While playing Frisbee can be very enjoyable and fun for the dog, it is extremely hard on his joints.
Remember, it is important to exercise daily; only exercising on weekends, for example, may cause more harm than good. Regular exercise in shorter sessions is always better than long work-outs on weekends. Warming the muscles prior to exercise and following exercise with a "warm-down" period are beneficial. Consult with your veterinarian regarding an exercise program appropriate for your dog.
Warmth and good sleeping areas: Most people with arthritis find that the symptoms tend to worsen in cold, damp weather. Keeping your pet warm, may help him be more comfortable. A pet sweater will help keep joints warmer. In addition, you may want to consider keeping the temperature in your home a little warmer.
Providing an orthopedic foam bed helps many dogs with arthritis. Beds with dome-shaped, orthopedic foam distribute weight evenly and reduce pressure on joints. They are also much easier for the pet to get out of. Place the bed in a warm spot away from drafts.
Massage and physical therapy: Your veterinarian or the veterinary staff can show you how to perform physical therapy and massage on your dog to help relax stiff muscles and promote a good range of motion in the joints. Remember, your dog is in pain, so start slowly and build trust. Begin by petting the area and work up to gently kneading the muscles around the joint with your fingertips using small, circular motions. Gradually work your way out to the surrounding muscles. Moist heat may also be beneficial.
Making daily activities less painful: Going up and down stairs is often difficult for arthritic dogs; it can make going outside to urinate and defecate very difficult. Many people build or buy ramps, especially on stairs leading to their yard, to make it easier for their dogs to go outside. Ramps also make car travel easier for arthritic dogs.
Glucosamine and Chondroitin: Glucosamine and chondroitin are two compounds that have been widely used to help manage osteoarthritis in both animals and humans.
Glucosamine is the major sugar found in glycosaminoglycans and hyaluronate, which are important building blocks in the synthesis and maintenance of joint cartilage in the joint. Chondroitin enhances the synthesis of glycosaminoglycans and inhibits damaging enzymes within the joint.
When a dog has hip dysplasia, the joint wears abnormally and the protective cartilage on the surface of the joint gets worn away and the resultant bone-to-bone contact creates pain. Glucosamine and chondroitin give the cartilage-forming cells (chondrocytes) the building blocks they need to synthesize new cartilage and to repair the existing damaged cartilage. These products are not painkillers; they work by actually healing the damage that has been done. These products generally take at least six weeks to begin to help heal the cartilage and most animals need to be maintained on these products the rest of their lives. These products are safe and show very few side effects. There are many different glucosamine/chondroitin products on the market, but they are not all created equal. Drs. Foster and Smith's line of Joint Care products or Cosequin are recommended.
Perna Mussels: Perna canaliculus, or green-lipped mussel, is an edible shellfish found off the shores of New Zealand. The soft tissue is separated from the shell, washed several times, frozen, and freeze-dried. It is then processed into a fine powder and added to joint care products. It is made up of 61% protein, 13% carbohydrates, 12% glycosaminoglycans (GAGs-an important component of connective tissue), 5% lipids, 5% minerals, and 4% water. It also contains glucosamine, a GAG precursor and one of the building blocks of cartilage. Glucosamine and GAGs are the compounds in the mussel believed to contribute to its beneficial effects.
Omega-3 Fatty Acids: Omega-3 fatty acids are often used for the management of the signs of atopy in dogs. Because of their anti-inflammatory properties, some have advocated their use in dogs with osteoarthritis.
Avocado/Soybean Unsaponifiables (ASUs): ASU's are an extract of avocados and soybeans. There is some very promising research that indicates that ASU's can help protect cartilage, support cartilage repair, and decrease the discomfort associated with osteoarthritis. ASU's are thought to enhance the action of glucosamine and chondroitin. ASU's are found in Doctors Foster and Smith Premium Joint Care 3.
Duralactin: Duralactin is a patented product obtained from the milk of grass-fed cows. It has been studied and marketed for the management of musculoskeletal disorders in dogs. This compound has anti-inflammatory properties and is available without a prescription.
It may be used as a primary supportive nutritional aid to help manage inflammation or in conjunction with non-steroidal anti-inflammatory drugs (NSAIDs) or corticosteroids.
Methyl-sulfonyl-methane (MSM): MSM is a natural, sulfur-containing compound produced by kelp. Sulfur is necessary for the production of collagen, glucosamine, and chondroitin. MSM is reported to enhance the structural integrity of connective tissue, and help reduce scar tissue by altering components that contribute to scar formation. MSM has been promoted as having powerful anti-inflammatory and pain reducing properties, and is thought to work by blocking the pain perception in certain nerve fibers before the pain impulse reaches the brain.
S-Adenosyl-L-methionine (SAMe, Denosyl SD4): A recent product, Denosyl SD4, has been advocated for the management of osteoarthritis in people. The efficacy of this product for the management of osteoarthritis in animals has not been fully determined; however it is being used as a treatment for liver disease in dogs and cats. It has both anti-inflammatory and pain relieving properties.
Injectable Disease-Modifying Osteoarthritis Agents:
Polysulfated Glycosaminoglycan (Adequan): Adequan is a product that is administered as an intramuscular injection. A series of shots are given over four weeks and very often this product produces favorable results. This product helps prevent the breakdown of cartilage and may help with the synthesis of new cartilage. The complete mechanism of action of this product is not completely understood, but appears to work on several different areas in cartilage protection and synthesis. The cost and the inconvenience of twice weekly injections are a deterrent to some owners, especially with the ease of giving oral glucosamine products.
Hyaluronic Acid (Legend): Hyaluronic acid is an important component of joint fluid. Including it in the management of osteoarthritis may protect the joint by increasing the viscosity of the joint fluid, reducing inflammation and scavenging free radicals. Most of the research on hyaluronic acid has been done in people and horses, but it may also be beneficial in dogs. Because this product is injected directly into the joint and it is not labeled for dogs its use must be under the direct supervision of a veterinarian.
|Never give human NSAID's to your pet without consulting your veterinarian.|
Carprofen (Rimadyl), etodolac (EtoGesic), deracoxib (Deramaxx), firocoxib (Previcox), tepoxalin (Zubrin) meloxicam (Metacam): These are non-steroidal anti-inflammatory drugs (NSAIDs) developed for use in dogs with osteoarthritis. They are very effective painkillers that also reduce inflammation. They are prescription products and because of potential side effects, careful adherence to dosing quantity and frequency must be followed. The manufacturers recommend that patients taking these medications have a thorough physical examination along with appropriate blood-work (especially tests for liver health) performed before starting these medications. In addition, patients taking these products should be periodically monitored to make sure that they are tolerating the medication. These products are often used initially with glucosamine therapy and then as the glucosamine product begins to work, the NSAID dose may be reduced or even eliminated. NSAID's (including aspirin) should never be combined unless directed by your veterinarian. Acetaminophen (Tylenol), and ibuprofen (Advil) have many potential side effects and are not recommended without veterinary guidance.
Buffered Aspirin: Buffered aspirin is also an anti-inflammatory and painkiller used in dogs. It can be used along with glucosamine/chondroitin products. With all aspirin products used in dogs, there is a risk of intestinal upset or in rare cases, gastric ulceration. Using buffered aspirin formulated for dogs makes dosage and administration much easier. Do NOT give your cat aspirin unless prescribed by your veterinarian.
Corticosteroids: Corticosteroids have been used for many years to treat the pain and inflammation associated with osteoarthritis, however, their use is controversial. Corticosteroids act as a potent anti-inflammatory, but unfortunately, they have many undesirable short and long-term side effects. Because of these side effects and the advent of newer, more specific drugs, corticosteroids are generally only used in older animals with flare-ups where all other pain control products have failed. Corticosteroids are a prescription product and come in both a pill and injectable form.
|When it comes to preventing the formation of hip dysplasia, there is only one thing researchers agree on; selective breeding is crucial.|
How do we prevent hip dysplasia?
When it comes to preventing hip dysplasia, there is only one thing that researchers agree on; selective breeding is crucial. We know that through selectively breeding animals with certified hips, we can significantly reduce the incidence of hip dysplasia. We also know that we can increase the incidence of hip dysplasia if we choose to use dysplastic animals for breeding. Breeding two animals with excellent hips does not guarantee that all of the offspring will be free of hip dysplasia, but there will be a much lower incidence than if we breed two animals with fair or poor hips. If we only bred animals with excellent hips it would not take long to make hip dysplasia a rare occurrence. If owners insisted on only purchasing an animal that had parents and grandparents with certified good or excellent hips, or if breeders only bred these excellent animals, then the majority of the problems caused by hip dysplasia would be eliminated. For someone looking to purchase a dog, the best way to lower the possibility of getting an animal that develops hip dysplasia is to examine the incidence of hip dysplasia in the litter's lineage. It is best to examine the parents and grandparents out to three or four generations.
There are many different theories on how to prevent the progression of hip dysplasia. As discussed earlier, poor nutrition, inadequate or improper exercise, and increased body weight may all contribute to the severity of osteoarthritis after the hip dysplasia has developed. Following solid recommendations for exercise and nutrition may help, but will never come close to controlling or eliminating the disease if stricter requirements for certified hips are not instituted or demanded.
Hip dysplasia is a widespread condition that primarily affects large and giant breeds of dogs. There is a strong genetic link between parents that have hip dysplasia and the incidence in their offspring. There are probably other factors that contribute to the severity of the disease.
Osteoarthritis of the hip is the result of the degeneration of the joint due to a laxity caused by hip dysplasia. Surgical and medical treatments are targeted to prevent and treat the resulting osteoarthritis. The best way to prevent hip dysplasia is through selection of offspring whose parents and grandparents have been certified to have excellent hip conformation.
Elbow dysplasia, more commonly seen in fast-growing large breed puppies, is not a simple condition to understand nor easy to explain. Elbow dysplasia is really a syndrome in which one or more of the following conditions are present:
- Fragmentation of the coronoid process
- Ununited anconeal process
- Elbow incongruity
Normal bone growth
Many bones in a newborn puppy are not just one piece of bone, but several different pieces of bone with cartilage in between. This is especially true of long bones of the limbs. As the puppy grows, the cartilage changes into bone and several pieces of a bone fuse together forming one entire bone. For instance, the ulna, a bone in the forearm starts out as 4 pieces of bone that eventually fuse into one.
Normal elbow anatomy
In the healthy dog, the elbow joint itself is fairly complicated. The elbow of the dog corresponds to ours anatomically but rests relatively closer to the chest wall than it does in man. The bones that form the joint are the humerus, ulna, and radius. The lower end of the humerus has two rounded knobs (the lateral and medial condyles) on it with a hole between them that extends completely through the bone (the supratrochlear foramen). The radius and ulna bones basically act as one bone as they are held tightly together by several ligaments. They move together at all times. The upper end of the ulna has a hook-like process that fits neatly into the supratrochlear foramen of the humerus and a curved ridge called the trochlear notch that fits against and rotates between the medial and lateral condyles. At the base of this notch and on either side of it are the medial and lateral coronoid processes that the condyles of the humerus rest on, therefore supporting the weight of the dog. Finally, there is the upper end of the radius that also lies between the coronoid processes of the ulna and it also helps support the weight of the animal as it is transmitted down through the humerus. In the normal dog, all of these surfaces that rub or articulate against each other are covered with cartilage and are perfectly smooth. They are constantly lubricated by the joint fluid that is contained by the capsule that surrounds the joint.
In osteochondrosis, there is an abnormality of the cartilage and the bone underneath it. In the elbow joint, this most commonly occurs on the medial condyle of the humerus. The cause of osteochondrosis may include genetic factors, trauma, and nutrition. The signs of this abnormal bone growth usually develop between 6 and 9 months of age, and generally appear as lameness. Osteochondrosisis is more common in rapidly growing, large breed puppies. In the condition termed osteochondrosis dessicans, a portion of cartilage loosens from the underlying bone. It may break loose and float free in the joint, or remain partially attached to the bone like a flap. In either case, this is an extremely painful situation.
Fragmentation of the medial coronoid process (FMCP)
Fragmentation means that the bone in this area of the ulna starts breaking up or degenerating. This occurs very early in the life of the dog, oftentimes before six months of age. We see it mostly in the larger breeds such as the German Shepherd, Golden Retriever, Rottweiler, Doberman, and the giant breeds. However, as we become better at diagnosing this disorder, it is being recorded in more and more breeds even some of the smaller ones such as the Springer Spaniel, Cocker Spaniel, and German Shorthair. Although the exact cause is unknown, it is thought to have strong genetic transmission, as it has been found to be passed from generation to generation in certain lines of several breeds. Osteochondrosis and a fragmented coronoid process frequently occur in the same joint.
Ununited anconeal process (UAP)
Generally, by 20-24 weeks of age, the anconeal process should have fused with the ulna. In UAP, the hook, or anconeal process, never attaches correctly to the rest of the ulna as the puppy is developing, but rather floats loose. It is held fairly close to where it should be by ligaments between it and other portions of the bone, but it is not solid enough to remain exactly where it should. This leads to joint instability, preventing the humerus and ulna from interacting correctly. Additionally, the loose anconeal process is often caught abnormally between the ends of the ulna and humerus thus irritating and bruising the articular surfaces. An ununited anconeal process is commonly found by itself with the elbow dysplasia syndrome, although it larger breeds it is often seen with fragmentation of the medial coronoid process.
If the radius and ulna do not grow at the same rate of speed, a condition called elbow incongruity can occur. This causes wear and tear on the cartilage as the humerus does not meet the appropriate surfaces on the radius and ulna. Thus some points of contact are overloaded and this can lead to fragmentation of the medial coronoid process and other abnormalities.
Symptoms of elbow dysplasia
Patients with elbow dysplasia will usually display an obvious limp, may hold the leg out from the body while walking, or even attempt to carry the front leg completely, putting no weight on it at all. Signs may be noted as early as four months of age. Many affected animals will go through a period between six and about twelve months of age, during which the clinical signs will be the worst. After this period, most will show some signs occasionally, but they will not be as severe. As these dogs continue to mature, there will probably be permanent arthritic changes occurring in the joint. This will cause many obvious problems and it may become necessary to utilize oral or injectable medications to make the animal more comfortable. Elbow dysplasia is therefore a lifelong problem for the affected animals. Some of these patients can be helped with surgery. In some, surgery can even eliminate the problem totally.
Diagnosis of elbow dysplasia
Many dogs will have more than one of the conditions that may contribute to elbow dysplasia. In addition, both elbows may be involved. The symptoms of front leg lameness and pain in the elbow lead us to think about elbow dysplasia as a diagnosis. However, there are other conditions that can affect the front leg of a young dog that will mimic the signs of elbow dysplasia very closely. Therefore, it is necessary to take radiographs (x-rays) of the elbow(s) to verify the diagnosis.
Of the above three, an ununited anconeal process is by far and away the easiest to show with x-rays. The fragmentation of the medial coronoid process and the osteochondrosis can be more difficult. The dog generally needs to be heavily sedated or anesthetized to obtain good x-rays, since the limb needs to be manipulated and positioned in ways that are often painful. High quality radiographs are a must. In addition, it may be necessary to have the radiographs sent to an expert veterinary radiologist who can discern the very minor changes that may appear in a dog with elbow dysplasia.
Treatment of elbow dysplasia
Treatment of elbow dysplasia varies with what distinct abnormalities are present. Fragmented coronoid process and osteochondrosis are often treated medically, without surgery. The young dog is placed on a regular, low-impact, exercise program (swimming is often preferred). Weight is managed carefully. Medications such as nonsteroidal anti-inflammatory drugs (NSAIDS) are given to decrease pain and inflammation. Depending on the severity of the condition, surgery may be performed to remove the fragmented process or cartilage flap.
United anconeal process is usually treated with surgery in which the ununited process is removed. In some instances, small pins or screws may be used to join the process with the rest of the ulnar bone.
Usually, after the dog is 12 to 18 months of age, the lameness will have become less severe and some dogs will function very well. The long-term prognosis (outlook), however, is guarded. Usually, degenerative joint disease (arthritis) will occur as the animal ages, regardless of the type of treatment.
Veterinarians who limit their practice to dogs and cats see a lot of skin problems. There are numerous conditions that cause problems with a dog or cat's skin, but the most common, by far, is allergies.
Symptoms of allergies
Dogs with allergies may show the following symptoms:
- Chewing on feet
- Rubbing the face on the carpet
- Scratching the body
- Recurrent ear infections
- Hair loss
- Mutilated skin
|A dog who is allergic to something will usually have skin problems and itching.|
A dog who is allergic to something will show it through skin problems and itching, i.e., pruritus. It may seem logical that if a dog is allergic to something he inhales (atopy) like certain pollen grains, he will have a runny nose; if he is allergic to something he eats (food allergy) such as beef, he may vomit; or if allergic to an insect bite (urticaria or hives), he may develop a swelling at the site of the bite. In reality, the dog will seldom have these signs. Instead, he will have a mild to severe itching sensation over his body and maybe a chronic ear infection.
In addition, allergic dogs will often chew on their feet until they are irritated and red. They may rub their faces on the carpet or couch, or scratch their sides and belly. Because the wax-producing glands of the ear overproduce as a response to the allergy, they get ear infections. Bacteria and yeast often "over grow" in the excessive wax and debris.
The skin lesions seen in an allergic dog are usually the result of him mutilating his skin through chewing and scratching. Sometimes there is hair loss, which can be patchy or inconsistent over the body leaving a mottled appearance. The skin itself may be dry and crusty, reddened, or oily depending on the dog. It is very common to get secondary bacterial infections of the skin due to these self-inflicted lesions.
When a dog is allergic to something, his body is reacting to certain molecules called 'allergens.' These allergens may come from:
- Weed pollens
- Fabrics such as wool or nylon
- Rubber and plastic materials
- Foods and food additives such as individual meats, grains, or colorings
- Milk products
- House dust and dust mites
- Flea bites
The body's response to an allergen
The reason that all these allergens cause itchy skin is that, simplistically, when allergens are inhaled, ingested, or come in contact with the dog's body, they cause the immune system to produce a protein referred to as IgE. This protein then fixes itself to cells called 'tissue mast cells' that are located in the skin. When IgE attaches to these mast cells, it causes the release of various irritating chemicals such as histamine. In dogs, these chemical reactions and cell types occur in appreciable amounts only within the skin.
Genetic factors and time influence allergies
Remember that dogs must be exposed to the allergen for some time before the allergy develops. Exceptions may occur such as an allergy to insect bites, which may develop after only a few exposures. The dog's body must learn to react to the allergen. It is a learned phenomenon of the immune system that is genetically programmed and passed from generation to generation in several breeds. Allergies are especially common in certain terriers such as the Scottish, West Highland White, Cairn, and Wire Haired Fox; Lhasa Apsos; and larger breeds such as the English and Irish Setters, Retrievers, and the Dalmatian. Allergies are also well documented in the Pug, Miniature Schnauzer, and English Bulldog.
|In pets, allergies usually start to develop between one and three years of age.|
In pets, allergies usually start to develop between one and three years of age. They may start as late as age six or eight, but over 80% start earlier. To make matters worse, as the animal ages, he usually develops allergies to additional things and the response to any one allergen becomes more severe.
Most allergies are the inhalant type and are seasonal (at least at first). The dog may be allergic to a certain tree pollen that is only present in the environment for three weeks out of the year, or the allergy may be to house dust mites which are in the environment year round.
A definitive diagnosis of an allergy and determination of exactly what the animal is allergic to can be made in two ways:
Allergy testing (intradermal or blood testing)
Eliminating things individually from the animal's environment until the culprit is isolated (this method is most often used when food allergies are suspected)
For example, a dog may start chewing his feet, scratching his sides, and rubbing his face on furniture every year for three weeks during the same month. These are often the signs of a seasonal allergy to something such as ragweed or tree pollen. In this case, the veterinarian may choose either tablets and/or a single injection that will suppress the allergy for the 3-4 weeks necessary when that allergen is in the environment. After a short treatment period, the animal is back to normal and only has to wait until the following year when he or she will be returned to the veterinarian with the same problem.
This can be a very important part of managing atopy. While it may be impossible to completely eliminate all of the offending agents, many can be reduced with minimal effort on the part of the owner. For avoidance therapy to have any benefit, the offending agents must be identified through intradermal skin testing. Avoidance is rarely a complete treatment in itself, but is used in conjunction with other treatments.
|House dust |
House dust mites
Keep pets out of room several hours when vacuuming
Change furnace filters regularly
Use a plastic cover over pet's bed
Wash bedding in very hot water
Avoid letting pets sleep on stuffed furniture
Avoid stuffed toys
Keep pets in uncarpeted rooms
Run air conditioner during hot weather
Change furnace filters regularly
Keep pets out of basements
Keep pets indoors when the lawn is mowed
Avoid dusty pet foods
Clean and disinfect humidifiers
Avoid large numbers of houseplants
Keep dogs out of fields
Keep grass cut short
Rinse dog's feet off after dog has been outside
Keep pets indoors during periods of high pollen counts
Topical therapy consists of shampoos and rinses and topical anti-itch solutions. Topical therapy offers immediate, but short-term relief. It is often recommended to bathe recommend atopic dogs at least once every two weeks with a hypoallergenic shampoo or colloidal oatmeal shampoo. Hydrocortisone shampoos may also be used. Weekly or even twice weekly shampoos may offer increased relief for some dogs.
In addition to bathing, it is helpful to simply wash off the dog's feet after he comes in from the outside. This will remove any allergens from his feet.
Topical solutions containing hydrocortisone may offer some relief. They are the most practical in treating localized itching. These products are very poorly absorbed into the bloodstream, and when used in moderation, do not create long-term side effects or problems associated with injectable or oral steroids. In addition, cooling salves and lotions may also be used. Care must be taken with these to ensure that they do not make the coat too greasy. Dogs may tend to lick off these preparations. After applying these preparations, it is recommended to get the dog involved in some activity to prevent him from licking the treated area.
Immunotherapy has been described as the mainstay of treatment for canine atopy. It is indicated in animals where the avoidance of antigens is impossible, symptoms are present for more than 4 to 6 months out of the year, and fatty acids and antihistamines do not provide satisfactory results.
An animal must undergo intradermal skin testing prior to hyposensitization. After the antigens to which the animal is allergic have been identified through testing, a commercially prepared injection containing the altered antigens is injected into the dog. Depending on the type of product used, a series of weekly or monthly shots are given. The animal then becomes de-sensitized to the offending allergens. Success is as high as 80% with this treatment plan. Treatment is time consuming and requires a dedicated owner and veterinarian. This treatment is an excellent option in severe cases of atopy, especially in young dogs. If you have an allergic pet that is not responding to conventional treatment, seriously consider this as a treatment option.
Omega-3 fatty acids
Fatty acids have been recommended for years to improve coat quality and shine. Recently, new research has shown that certain fatty acids - the omega-3 fatty acids - are also very beneficial in the management of allergies in dogs and cats. Omega-3 fatty acids work in the skin to help reduce the amount and effects of histamine and other chemicals that are released in response to allergies. Not every allergic pet responds to omega-3 fatty acids. Some pets show improvements, others have a complete cure, and others show no change after being on the omega-3 fatty acids. Most pets need to be on the omega-3 fatty acids daily for several weeks to months to notice significant improvement. Omega-3 fatty acids are very safe and have very few side effects. Studies show that when omega-3 fatty acids are used in conjunction with other treatments, such as antihistamines, the use of steroids can often be decreased or discontinued. Be sure to use an omega-3 fatty acid supplement derived from fish oil. Other types of fatty acids (such as omega-6 fatty acids) can actually make some allergies worse. It is often best to use the omega-3 fatty acid supplements in conjunction with a diet lower in fat.
Antihistamines are widely used in both the human and animal medical fields. Most of the antihistamines used in veterinary medicine are antihistamines that were designed for and used primarily by humans. Antihistamines have been shown to be effective in controlling allergies in up to 30% of dogs and 70% of cats. When used as part of a treatment plan including fatty acids and avoidance, the percent of respondents goes much higher.
Every animal will respond differently to each of the different antihistamines. Therefore, several different antihistamines may have to be used before an effective one is found. Every antihistamine has a different dose and risk of side effects. Antihistamines should be used with veterinary guidance. Some common side effects include sedation, hyperactivity, constipation, dry mouth, and decreased appetite. The correct antihistamine given at the proper dose should not cause unwanted side effects. For severely itchy dogs, mild sedation may be a positive and desired side effect.
Antihistamines come in several forms including H1 and H2 blockers. While the H2 blockers (Claritin, Seldane, and Hismanal) have been shown to be very effective in treating human allergies, they have not been shown to be effective in treating canine or feline allergies, and are therefore, not recommended for pet use. There are many different H1 antihistamines available on the market, but veterinary use is usually restricted to the following.
Cyclosporine, in the form of the brand name drug Atopica, is being used very successfully in the treatment of atopy in dogs, especially those with severe allergies. The most common side effects are diarrhea and vomiting. It does not work immediately, but may take 3-4 weeks to see an effect. It t may be used for short periods of time for seasonal allergies, or can be given long-term for year-round atopy.
Steroids are extremely effective for relieving severe itching and inflammation. The problem is that they can have many short and long-term side effects, if not used correctly. If used correctly, they can be as safe as any other drug that we use. The problem is that they work so well that they are often overused. Because of their potential side effects, they should be used carefully, and at the lowest effective dose. They are usually reserved as one of the last lines of treatments, but if nothing else works, use the steroids.
Steroids are usually administered in one of two forms, injectable and in tablet form. The steroids being discussed here are corticosteroids and are not the anabolic steroids used by body builders. Anabolic steroids are a completely different drug and have no application in treating animal allergies. There are many different forms of corticosteroids currently available on the market. They vary widely in their duration of activity and strength.
Injectable: Injectable forms of steroids include betamethasone, dexamethasone, flumethasone, methylprednisolone, and triamcinolone. These agents are usually given intramuscularly and have between one week and six months duration depending on the product, the dose, and the individual animal.
|Steroids can be used effectively and safely, if a careful dosage schedule is followed.|
Oral supplementation allows a more accurate and tailored dose, but injectables may be preferred in several situations. Injectables are preferred in animals that are very difficult to give pills to, and in animals that need immediate relief. Once the injection is given, it is impossible to reverse its effects and side effects. With oral administration, if unwanted side effects appear, the product can be discontinued and the side effects will diminish.
Oral: As mentioned earlier, it is much easier to customize an individual dosing program with the tablet form. The affected animal usually begins with daily therapy for a period of three to five days, and then the dose is reduced to every other day dosing. If the animal needs to be treated for more than a couple of weeks, then the dose is halved weekly until a minimum therapeutic level can be established. The goal with all steroids is to use the minimum dose necessary to alleviate the symptoms. By taking this approach, the side effects are eliminated or reduced.
Side Effects: The potential side effects associated with steroid use in dogs are numerous. Side effects can appear with any duration or form of steroid therapy. Each animal responds differently to each type of treatment. However, the number and severity of the side effects are very closely related to dose and duration of treatment. Most of the side effects associated with minimum effective dose short-term therapy are mild and resolve once therapy stops. The most common symptoms include increased water consumption, increased urination, increased appetite (weight gain), depression, hyperactivity, panting, and diarrhea.
Long-term use has the risk of creating more permanent and severe damage. Some high dose, long term side effects include increased incidence of infections, poor hair coat and skin, immunosuppression, diabetes mellitus, adrenal suppression, and liver problems. The potential problems can be severe, however, it must be stressed that these side effects are dose dependent. Despite the potential side effects, steroids can be used effectively and safely, if a careful dosage schedule is followed. Still, because of the availability of safer yet effective therapies, steroid use is reserved until all other treatment options have been exhausted. Several studies have shown that if fatty acids and antihistamines are used concurrently with steroids that the amount of steroids needed to offer relief is greatly reduced.
Treatment of concurrent infections
Since bacterial and yeast skin infections are common in dogs with allergies, it is important to treat the infections as well as the atopy. A yeast infection would be treated with an antifungal medication. A skin culture and sensitivity may be performed to best identify which antibiotic to use in the case of bacterial infections. In addition, special shampoos may be helpful to control these infections.
OCD - Osteochondritis Dissecans.
Osteochondritis dissecans, commonly known as OCD, is a disease of the cartilage that can affect various joints in a dog. In any joint in the body, two bones come together and movement is allowed between them. Where the two bones meet an exceptionally smooth area of cartilage covers their surfaces. This acts as a cushion and protects the underlying bone. If anything disrupts this smooth cartilage surface, movement of the joint becomes painful. In a dog with OCD, this cartilage is damaged or grows abnormally. Instead of being attached to the bone it covers, it separates or cracks. A loose flap of cartilage may form, or an entire piece may break loose. These are known as joint mice.
Who gets OCD?
OCD is primarily a problem in large or giant breed dogs. It has been reported in small dogs and cats, though it is not very common. It affects male dogs more frequently than females, most likely due to the males' larger size and increased stress on the joint. It generally occurs when the animal is between 4 and 10 months of age, though it can show up in older dogs. There are several breeds that despite being larger breeds have decreased incidences of the disease including the Doberman Pinscher, Collie, and Siberian Husky.
What are the symptoms of OCD?
OCD may affect the shoulder, elbow, knee or hock, although the shoulder is most commonly affected. The symptoms are lameness in the affected limb. Some dogs have a barely noticeable limp and others are unable to bear any weight on the leg. The lameness tends to worsen after periods of exercise and improves after rest. When it affects the shoulder, a shortened forelimb stride may be noted due to reluctance to flex and extend the shoulder joint. Occasionally, the disease will affect both limbs simultaneously and the dog may be reluctant to move.
How is OCD diagnosed?
Diagnosis is based on history, physical exam, and radiographs (x-rays). On physical exam, we notice joint pain. For instance, most healthy dogs show no resistance when their shoulder joint is fully flexed and extended. However, if they have an OCD lesion in their shoulder, they may resist shoulder manipulation and may even cry out in pain when it is attempted. In addition, this flexion and extension of the shoulder joint may worsen the lameness.
Radiographs of the affected joint are taken to confirm the diagnosis. The dog is often sedated so that full relaxation of the joint can be obtained. Several views of the affected joint and the healthy joint on the other side are taken for comparison. A change of the bone underneath the damaged cartilage is often visible. If the radiographs are not confirmatory but OCD is still suspected, radiographs may be taken again in 2 to 3 weeks.
What causes the formation of OCD?
|Trauma to the joint, hereditary factors, rapid growth, hormonal imbalances and nutrition may contribute to the formation of OCD.|
The cause of OCD is considered to be multifactorial. It is thought that there are several factors that contribute to the formation of OCD lesions including trauma to the joint, genetics, rapid growth, hormone imbalances, and nutrition.
Trauma, whether chronic or acute, may contribute to the formation of OCD lesions. Injury to the surface cartilage may lead to the separation of the cartilage from the bone or cause a decrease in blood supply that leads to cartilage flap formation.
It appears that there is a genetic link between parents and offspring and the formation of the disease. Certain breeds and genetic lines are much more likely to develop the disease. Careful screening of parents against this disease is recommended during the selection of all breeding animals.
OCD usually occurs during periods of rapid growth. Therefore, it has been suggested that nutrition that creates rapid growth may lead to the increase in incidence of the disease.
How is OCD treated?
There are currently two ways to treat OCD, conservative medical treatment or surgical removal of the lesion. Conservative treatment may be indicated for dogs that have early mild symptoms of OCD or where a specific lesion cannot be identified on radiographs. Conservative treatment consists of strict rest for 4 to 8 weeks. Leash walking is permitted but no running or playing is allowed. Anti-inflammatories and painkillers such as carprofen (Rimadyl) may be indicated. In addition, the use of glucosamine/chondroitin products has been suggested, yet there are no current studies that confirm their beneficial use in this particular disease. Conservative treatment may be difficult in young, active puppies who may still need to undergo surgery, if the symptoms do not improve.
Surgery is indicated in animals that show severe symptoms, in cases where large lesions are identified on radiographs or when conservative treatments fail. The surgery is very straightforward. The affected joint is opened and the offending flap, defect, or joint mouse is removed. The prognosis is generally good when the shoulder joint is affected. With other joints, degenerative joint disease (osteoarthritis) is more common. When the elbow is affected, the OCD may contribute to the development of other abnormalities in that joint.
How is OCD prevented?
Prevention consists of careful selective breeding that avoids the breeding of animals with a history of OCD. Young large and giant breed dogs should not undergo strenuous activity, particularly jumping activities. Housing on hard concrete surfaces has been linked to increased OCD lesions in pigs and may also contribute to problems in the dog. Providing a good balanced diet that promotes even, sustained growth is also recommended. Talk to your veterinarian about what is best to feed your dog.
OCD is a cartilage problem that affects young large and giant breed dogs. It is due to several factors including genetics, trauma, rapid growth, and nutrition. Treatment is either conservative including strict rest, or surgical removal of the damaged cartilage. Prevention is aimed at good genetic selection, reduced activity, and careful feeding.
What is panosteitis?
Panosteitis is a bone disease of dogs that is characterized by bone proliferation and remodeling. It is often painful and can last as long as 18 months, though more commonly it lasts from 2 to 5 months. It is characterized by lameness that often comes and goes and changes from leg to leg. It is a common problem in several large breeds and the cause is currently unknown. The treatment is symptomatic but the outcome is usually very good.
Who gets panosteitis?
|Panosteitis is most common in large breed dogs between 6 and 18 months of age.|
Panosteitis is most common in large breed dogs between 6 and 18 months of age. Occasionally, middle-aged German Shepherds will have a bout of panosteitis. It affects dogs worldwide and has been recognized and studied since the 1950's. Male dogs are much more likely to get panosteitis then females. There is a higher incidence in several breeds including German Shepherds, Great Danes, Doberman Pinschers, Golden Retrievers, Labrador Retrievers, Rottweilers, and Basset Hounds.
What causes panosteitis?
The cause of panosteitis is currently unknown. There have been many theories as to the cause of this disease. Originally, it was suspected that the disease was caused by a bacterial infection. However, several investigational studies failed to isolate any bacteria. In addition, the disease responds poorly to antibiotics, further suggesting a cause other than bacterial.
Other studies showed that if bone marrow from affected dogs was injected into the bones of healthy dogs, the healthy dogs would contract the disease. It has therefore been speculated that a virus may cause the disease. The high fever, tonsillitis, and altered white blood cell count would also go along with the viral theory. Another interesting twist to the viral theory is that panosteitis was first identified as a problem at the same time that modified live distemper vaccines became widely available on the market. Since wild distemper virus can be isolated from bone tissue, some researchers feel that there might be a link between distemper virus vaccine and panosteitis, however, more research in this area will need to be done before any serious speculations can be made.
Another theory is that panosteitis might have a genetic link. Because of the greatly increased incidence in certain breeds and families of dogs, it is very likely that there is a genetic component involved in this disease.
Lately, there have been some claims that nutrition, particularly protein and fat concentrations in the diet, may have an impact on the incidence of the disease. But here again, more research needs to be done to substantiate these claims. Most likely this is a multifactorial disease that has several different causes including viral, genetic, and possibly nutritional.
What are the symptoms?
Presenting symptoms include a history of acute sudden lameness not associated with any trauma. It is usually a large breed male dog between the ages of 6 to 18 months. There are periods of lameness lasting from 2 to 3 weeks and it may shift from leg to leg. The most commonly affected bones are the radius, ulna, humerus, femur, and tibia, though the foot and pelvic bones may also be involved. The dog may show a reluctance to walk or exercise. When the affected bones are squeezed, the dog reacts painfully. Occasionally, affected dogs will have a fever, tonsillitis, or an elevated white blood cell count.
How is panosteitis diagnosed?
Panosteitis is often diagnosed based on a combination of presenting signs and radiographs (x-rays). The presenting symptoms are listed above. If a dog is suspected of having panosteitis, then radiographs are indicated to confirm the diagnosis. Individual radiographs of each affected limb should be taken. Often, radiographs of the unaffected limbs are also taken to compare the bone changes. In early forms of the disease, a subtle increase in bone density is observed in the center part of the affected bones. During the middle part of the disease, the bone becomes more patchy or mottled in appearance and the outer surface of the bone may appear roughened. In the late phase, the bone is still slightly mottled, but is beginning to return to a more normal appearance.
How is panosteitis treated?
There is no specific treatment for the disease. Since this condition is often very painful, painkillers such as buffered aspirin or carprofen (Rimadyl) are recommended. (Do NOT give your cat aspirin unless prescribed by your veterinarian.) These products are used as needed to help control the pain. Antibiotics are not routinely used unless there are indications of concurrent infections. In severe cases, steroids are used, but because of the potential long-term side effects of these drugs, painkillers are often tried first. This disease is self-limiting and after it runs its course, there are very few long-term side effects or need for further treatment. As mentioned earlier, the disease usually lasts for two to five months, but can last much longer. There are several conditions with similar symptoms, so if a dog continues to have symptoms after the normal period of time or is not responding to treatment, she should be reevaluated.
How is panosteitis prevented?
There is currently no way to prevent the disease. However, because of the potential genetic link, breeding animals should be screened to ensure that they are not potential carriers of the disease. Despite the numerous puppy foods catering to large breed dogs, there is no current evidence that confirms that these foods will lower the incidence of the disease when compared to standard commercial puppy food. If an animal shows symptoms of the disease, they should be promptly diagnosed and treated and exercise and activity should be reduced until the symptoms have gone away.
Gastric dilatation-volvulus (GDV) is also known as "bloat," "stomach torsion," or "twisted stomach." Bloat is an extremely serious condition, and should be considered a life-threatening emergency when it occurs. There are not home remedies for bloat, therefore dog owners must contact their veterinarians immediately if they suspect that their dog has bloat. Dogs can die of bloat within several hours. Even with treatment, as many as 25-33% of dogs with GDV die.
The gastric dilatation is one part of the condition and the volvulus or torsion is the second part. In bloat (dilatation), due to a number of different and sometimes unknown reasons, the stomach fills up with air and puts pressure on the other organs and diaphragm. The pressure on the diaphragm makes it difficult for the dog to breathe. The air-filled stomach also compresses large veins in the abdomen, thus preventing blood from returning to the heart. Filled with air, the stomach can easily rotate on itself, thus pinching off its blood supply. Once this rotation (volvulus) occurs and the blood supply is cut off, the stomach begins to die and the entire blood supply is disrupted and the animal's condition begins to deteriorate very rapidly.
Not all dogs that have a gas buildup and resultant dilatation develop the more serious and life threatening volvulus. However, almost all dogs that have a volvulus develop it as a result of a dilatation.
Bloat is a very serious and life threatening condition. Understanding the signs, prevention, and need for prompt treatment will help reduce the risk of mortality if your dog develops this problem.
What dogs are more susceptible?
There is a definite link between the likelihood of occurrence of GDV and the breed and build of the dog. GDV is much more likely to occur in large breeds with deep, narrow chests. The problem can occur in small dogs, but only rarely. The University of Purdue conducted a study of hundreds of dogs that had developed GDV, and they calculated a ratio of likelihood of a particular breed developing the problem as compared to a mixed breed dog. For example, using the GDV risk ratio, a Great Dane is 41.4 times more likely to develop GDV than a mixed breed dog.
|Breed ||GDV Risk Ratio ||Risk Rank |
Old English Sheepdog
German Shorthaired Pointer
Chesapeake Bay Retriever
English Springer Spaniel
In addition to breed predilection, there appears to be a genetic link to this disease. The incidence is closely correlated to the depth and width of the dog's chest. Several different genes from the parents determine these traits. If both parents have particularly deep and narrow chests, then it is highly likely that their offspring will have deep and narrow chests and the resulting problems that may go with it. This is why in particular breeds we see a higher incidence in certain lines, most likely because of that line's particular chest conformation.
Dogs over 7 years of age are more than twice as likely to develop gastric dilatation and volvulus as those who are 2-4 years of age.
Male dogs are twice as likely to develop gastric dilatation and volvulus as females. Neutering does not appear to have an effect on the risk of bloat.
Dogs fed once a day are twice as likely to develop GDV as those fed twice a day. It appears that dogs who eat rapidly or exercise soon after a meal may also be at increased risk.
Dogs that tend to be more nervous, anxious, or fearful appear to be at an increased risk of developing bloat.
What causes gastric dilatation and volvulus?
There is not one particular activity that leads to the development of GDV. It appears that it occurs as a combination of events. Studies of the stomach gas that occurs in dilatation have shown that it is similar to the composition of normal room air suggesting that the dilatation occurs as a result of swallowing air. All dogs, and people for that matter, swallow air, but normally we eructate (burp) and release this air and it is not a problem. For some reason that scientists have not yet determined, these dogs that develop bloat do not release this swallowed gas. There are currently several studies looking into what happens physiologically in these dogs that develop GDV.
What are the signs?
The most obvious signs are abdominal distention (swollen belly) and nonproductive vomiting (animal appears to be vomiting, but nothing comes up) and retching. Other signs include restlessness, abdominal pain, and rapid shallow breathing. Profuse salivation may indicate severe pain. If the dog's condition continues to deteriorate, especially if volvulus has occurred, the dog may go into shock and become pale, have a weak pulse, a rapid heart rate, and eventually collapse. A dog with gastric dilatation without volvulus can show all of these signs, but the more severe signs are likely to occur in dogs with both dilatation and volvulus.
How is gastric dilatation and volvulus treated?
|Even with treatment, as many as 25-30% of dogs with GDV die.|
When the dog is presented to the hospital his condition is assessed. Blood samples are generally taken and tested to help determine the dog's status. Usually the animal is in shock, or predisposed to it, so intravenous catheters are placed and fluids are administered. Antibiotics and pain relievers may be given.
The air in the stomach is removed either by passing a stomach tube or inserting a large needle into the stomach and releasing the gas. After the animal is stabilized, x-rays are taken to help determine whether or not a volvulus is present.
Some dogs with GDV develop a bleeding disorder called disseminated intravascular coagulation (DIC), in which small clots start to develop within the dog's blood vessels. To prevent or treat this condition, heparin, an anticoagulant, may be given.
The heart rate and rhythm are closely monitored. Some dogs with GDV develop heart arrhythmias, and this is a common cause of death in dogs with GDV. Dogs that already have a heart disease or are prone to heart arrythmias are generally treated with appropriate medications.
Once the dog is stabilized, abdominal surgery is usually indicated to accomplish three things:
Assess the health of the stomach and surrounding organs. If areas of the stomach or spleen have been irreversibly damaged, they are removed. In such a case, the chances for recovery are very poor, and euthanasia may be an alternative.
Properly reposition the stomach
Suture the stomach in a way to prevent it from twisting again (a procedure called gastropexy). If gastropexy is not performed, 75-80% of dogs will develop GDV again.
After surgery, the dog is closely monitored for several days for signs of infection, heart abnormalities, DIC, stomach ulceration or perforation, and damage to the pancreas or liver. Antibiotics and additional medications may need to be given.
How is gastric dilatation and volvulus prevented?
Despite adopting all of the recommendations listed below, a dog may still develop GDV. Because of the genetic link involved with this disease, prospective pet owners should question if there is a history of GDV in the lineage of any puppy that is from a breed listed as high risk. In addition, the following recommendations should be followed:
Owners of susceptible breeds should be aware of the early signs of bloat and contact their veteriarian as soon as possible if GDV is suspected.
Owners of susceptible breeds should develop a good working relationship with a local veterinarian in case emergency care is needed.
Large dogs should be fed two or three times daily, rather than once a day.
Water should be available at all times, but should be limited immediately after feeding.
Vigorous exercise, excitement, and stress should be avoided one hour before and two hours after meals.
Diet changes should be made gradually over a period of three to five days.
Susceptible dogs should be fed individually and, if possible in a quiet location.
Some studies suggest that dogs who are susceptible to bloat should not be fed with elevated feeders; other studies have not found this to be true. It is recommended, however, that dogs at increased risk be fed at floor level.
Some studies have associated food particle size, fat content, moistening of foods containing citric acid, and other factors with bloat. At this time, no cause-and-result relationships between these factors and bloat have been verified.
Dogs that have survived bloat are at an increased risk for future episodes; therefore prophylaxis in the form of preventive surgery or medical management should be discussed with the veterinarian.
Bloat is a life threatening condition that most commonly affects large-breed, deep-chested dogs over two years of age. Owners of susceptible breeds should be knowledgeable about the signs of the disease, since early and prompt treatment can greatly improve the outcome. By following the preventive measures recommended, pet owners can further reduce the likelihood of their pet developing this devastating condition.
ENTROPIAN & ECTROPIAN
Entropian, where the eyelid, along with the eyelashes, rolls into the eye, leading to possible ulcerations of the cornea. Surgery is required to correct this condition.
Ectropian, where the eyelid rolls outward, and can also causes irritation to the cornea and conjunctiva. This condition can sometimes just be cosmetic, with the eye looking red and droopy, however if there is irritation, corrective surgery may be required.
Link to Entropian & Ectropian information and surgery explanations website.
Almost daily every animal hospital receives a call about canine eye problems; and the diversity of concern expressed by the dog’s caretaker runs a wide spectrum. There are times when veterinarians will check a frantic and anxious client’s dog only to discover an insignificant soreness in the dog’s supporting tissues around the eye (called conjunctiva). The very next “eye case” may be an advanced corneal ulcer that has allowed internal contents of the eye to actually protrude through the corneal surface! And that client might calmly state, “It’s been like that for two weeks but we though it would clear up”.
Fortunately in most veterinary practices the entire staff has been directed to prioritize all calls that express concern about a potential ocular difficulty. The reason for expediting the evaluation of any case relating to eye difficulties is that there is no way for verbal description to convey the true nature or severity of the problem. Seemingly innocent conditions can fool you… and result in an ocular emergency rather rapidly. These cases simply must be seen right away.
Let’s take the “squinting dog” as an example. Surely any dog might develop a mild irritation in an eye and squint for a few moments, and extra tear production would be expected, too. But without direct examination of the eye and attendant structures, no one (not even a Specialist in Veterinary Ophthalmology) would know if the squinting is due to a tiny scratch on the cornea, a cinder hiding beneath the third eyelid or a penetrating wound from a carelessly aimed BB gun! And one of the very first signs of systemic diseases such as Blastomycosis or cancer could be an innocent looking squint.
I asked a Specialist in Veterinary Ophthalmology, Deborah S. Friedman, D.V.M., of Animal Eye Care, in Fremont, California what the most common eye condition might be that could potentially fool the dog’s caretaker into delaying an eye exam. Her reply was… “Glaucoma comes immediately to mind. In many cases owners delay treatment of glaucoma until it is far too late. If the intraocular pressure in the eye is elevated for more than 24-48 hours, permanent damage is the usual outcome and this usually means blindness and sometimes loss of the eye. Signs of glaucoma can be very subtle at first and could include a dilated pupil that responds poorly or not at all to light, a cloudy cornea, a red appearance to the eye, and poor vision. Glaucoma can be dangerous because many of the signs of glaucoma are similar to simple conjunctivitis.”
A good general rule for all dog owners to follow is to have any eye or adjacent tissue dysfunction evaluated by a veterinarian without delay. As Friedman states “In my opinion, any injury to the eye (from cat fight, thorn, foxtail, BB gun, caustic substance etc.) should be brought to the attention of a veterinarian immediately (within 12 hours if possible). With eye injuries, the sooner the specific problems are identified and treated the better the chance of saving eye function”.
During routine physical exams internal disorders are often first recognized by subtle changes in the normal appearance of eye structures. A yellowish appearance of the normally white sclera, undetected by the pet ‘s caretaker, signals to the veterinarian that there is likely to be a liver or red blood cell dysfunction. And a faint haziness in the normally transparent cornea can prompt the need to evaluate liver or pancreas function. Tumors of any of the eye structures can occur and need to be addressed at the earliest possible time in their development.
Puppies and Eye Disorders
If you are about to acquire a new pup be sure to become informed about common eye disorders for the breed of interest. For example, Friedman states “Cocker Spaniels frequently develop dry eye (see photo: Dry Eye) and glaucoma. Bichon Frise, Cocker Spaniels, Poodles, and Boston Terriers among other breeds often develop cataracts (see photo: Cataracts). If a potential owner is aware that the breed they are interested in has inherited eye problems the buyer can educate themselves about what to look for.” The more you know about your preferred breed the better your chances of obtaining a healthy dog. One commonly seen condition in pups, called entropion, is readily seen upon close inspection. This rolling inward of an eyelid will surely require surgery to eliminate the corrosive action of the lid hairs on the cornea; and potentially the condition could be passed on to any future offspring.
Patricia J. Smith, MS, D.V.M., Ph. D., Diplomate, American College of Veterinary Ophthalmologists and a colleague of Dr. Friedman at Animal Eye Care lists some common ocular problems in puppies. Become familiar with these disorders and be prepared to closely scrutinize any new pup for signs of these common difficulties:
Common Ocular Disorders In Puppies1.Entropion… inward folding of an eyelid where lid hairs contact the cornea (Shar Pei, Cocker Spaniel, Rottweiler, Labrador Retriever, etc.)
2. Cherry Eye… prolapsed gland of the third eyelid. (Bulldogs, Cocker Spaniels, Poodles, etc.) (See photo: Cherry Eye)
3. Ectopic Cilia… an abnormal eyelash that grows through the conjunctiva and is usually very painful and almost always causes an ulcer. (See Photo: Corneal Ulcer)
4. Distichiasis… abnormal position of eyelashes on a lid margin that result in irritation of the eye.
5. Dermoid…congenital defect where haired skin is located in an abnormal place on an eye and will often irritate the cornea and can cause ulcers.
6. Cataracts… opacity of the lens. Inherited cataracts can often appear in young dogs, in most cases a veterinarian or veterinary ophthalmologist will have to make this diagnosis; owners are often
unaware of small focal cataracts. There are also late onset cataracts that may not show up until middle or older age.
7. Follicular Conjunctivitis… itchy, reddened conjunctival tissues, tearing, squinting, often related to allergies.
8. Puppy Pyoderma or Puppy Strangles… eyelid abscesses associated with generalized skin pustules.
9. Dry Eye (Keratoconjunctivitis sicca or KCS)… lack of or inadequate production of tears. Sometimes this can be congenital in which case it is often very serious. Pug, Lhasa Apso, Shih Tzu are some of the breeds that may be born with dry eyes.
When you visit a breeder and evaluate pups for purchase it is best to do a careful and critical evaluation of any pup’s eyes before you make that purchase decision. Bring a penlight along and shine it directly into and at an angle to each eye. There should be no specks in the cornea, the pupil should be dark, the iris should constrict when the light enters the eye, and there should be no tiny stray eyelashes directed from the lids toward the cornea (Distichiasis).
As Friedman says “Conditions that the owner may think are trivial, may in fact be the early stages of something more serious. Often dogs are stoic and do not exhibit blatant signs of pain.” So don’t be fooled by subtle eye problems… they may not be so innocent after all. Do a thorough inspection of any new pup’s eyes and associated structures before you decide to make it a part of your “family” or breeding stock. And in any dog, if ordinary first aid provides no improvement in eye discomfort within 12 hours, be sure to obtain a veterinarian’s evaluation.