HIP DYSPLASIA

Source: The Dog Scene

What is it?

Dysplasia literally means abnormal, so hip dysplasia literally translates as abnormal formation of the hip socket. The hip is a ball and socket joint, in a normal hip the ball fits snugly into the socket, forming a pivot point. Dogs which have a genetic predisposition for hip dysplasia are born with normal hips. However, as the dog grows, the structure of the hip joint becomes badly formed, and the ball no longer fits snugly into the socket and therefore does not rotate smoothly. Although this problem is more common in larger breeds, smaller breed dogs and mongrels are not immune from it. Ultimately, the end result arthritis and a painful and crippling degenerative joint disease.

What are the Symptoms?

The severity of the symptoms obviously depends upon the degree of the dysplasia. More often than not the dog becomes lame and may be unwilling to run and play as much as he used to. He often starts to have trouble getting up or climbing stairs. If and older dog, he may perform a "bunny hop" when running, or walk with a "waddle" and become reluctant to exercise.

Diagnosis

There are many diseases which display the same symptoms as hip dysplasia, therefore the only true way to diagnose hip dysplasia is by a complete physical and neurological examination, and then x-ray of the hips.

What causes it?

Hip dysplasia is a multifactorial trait, which means that a number of different factors can contribute to it. However, hip dysplasia is basically a genetic trait and will not develop if the hereditary factor is not there to begin with.

The environment plays a large part in whether or not a dog will suffer from hip dysplasia.

Nutrition is the greatest contribution. Puppies should be kept lean and not fat, obviously a puppy which is carrying round too much weight will exacerbate any degeneration of the joint. Research has also shown that giving a diet too high in protein and calcium also exacerbates the condition. Rapid growth in a young puppy also contributes, and, in most cases, the rapid growth rate is directly related to feeding a high calorie diet to puppies. Over supplementation of calcium has likewise been shown to be a major factor in the development of skeletal disease in puppies.

Exercise is the other main contribution. Many people over-exercise young puppies, or give them the wrong type of exercise. The wrong type of exercise can include forced running for any distance and too much exercise on tarmac or other hard surfaces. Up to at least six months of age, exercise on hard surfaces should be kept at a minimum. Correct exercise for puppies includes running and playing in the garden or in a park, although games that involve jumping and very rough play should be avoided, and the puppy should be allowed to rest as soon as he has had enough and must not "over-do" it. Swimming is an excellent form of exercise which builds up the muscles without putting stress on the joints.

How is it treated?

The treatment depends a lot upon the severity of the hip dysplasia and the age of the dog concerned, and veterinary treatment must be sought.

Any dog with hip dysplasia should be kept fit and trim as any excess weight will obviously aggravate the condition, but good muscle tone will help to support the dog's weight. Swimming is an excellent form of exercise which builds up the muscle without stress to the joints.

Non-steroid anti-inflammatory drugs, such as aspirin and carprofen, can often help manage pain. Research has shown that Vitamin C can also reduce the inflammation in the affected joints. Some people have also reported success with holistic medicines.

However, in some dogs the arthritis in the joint can become so painful that if cannot be controlled medically. When the pain becomes this bad, there are various surgical procedures which can be done to relieve the pain. Each procedure has its pros and cons, and different veterinary surgeons may have more experience, and therefore be more skilled, with a particular type of surgery.

One such procedure is called a femoral head osteotomy. This involves removing the head and neck of the femur so that the bone does not contact bone, and a fibrous scar tissue then forms a "false" joint. As the dog's muscles must be strong enough to support the dog's weight on the false joint, regular exercise is very important. Another surgical procedure is hip replacement. This is the same as the human hip replacement, the diseased joint is taken out and an artificial joint is inserted.

Can it be Prevented?

Hip dysplasia is an inherited disease with a polygenic (influenced by more than one gene) mode of inheritance. Total elimination of Canine Hip Dysplasia is an unrealistic goal, but by selectively breeding dogs with good hips, breeders can reduce the incidence of hip dysplasia. In this respect, the British Veterinary Association, along with The Kennel Club, run a scheme to test for hip dysplasia, which should aid the breeder when choosing breeding stock.

Nutrition and exercise factors have been discussed above, and we know that with the correct diet and exercise it is possible to ensure that the hip dysplasia is not expressed, causing lameness and pain. Each breed has different requirements, and advice on this should be sought from both the breeder and a veterinary surgeon.

ELBOW DYSPLASIA

Source: The University Of Liverpool

 
What is it?  

Elbow dysplasia is a group of four slightly different diseases associated with abnormal development of this joint in puppies:
 

• Fragmented medial coronoid process

• OCD of the medial humeral condyle

• Ununited anconeal process

• Incongruity of the elbow joint
  
  The most common form is fragmented medial coronoid process and this involves a small fragment of cartilage and bone loose within the joint that causes inflammation (arthritis). The location of the coronoid process within the elbow joint is shown below in this model.
  
  What sort of dogs are affected?

Typically, the diseases causes lameness and pain in dogs aged 5-18 months. Certain breeds are particularly at risk for these disorders:

Fragmented coronoid process: Many medium to large breed pedigree dogs, but especially Labradors, Golden Retrievers, Rottweilers, Bernese Mountain Dogs, Bullmastiffs.
OCD: Many medium to large breed pedigree dogs, but especially Labradors, Golden Retrievers.
Ununited anconeal process: German Shepherd Dog, Bassett Hound
What causes these diseases?
The cause of elbow dysplasia is not fully understood. Certainly there is a complex genetic basis and it is likely that several different genes are involved. It is also likely that environmental factors (exercise, growth rate, nutrition) play a role. At Liverpool we are investigating the genetic basis of the disease in collaboration with colleagues at CIGMA at the University of Manchester.

What are the signs of these diseases?
All types of elbow dysplasia can cause pain and lameness although in some dogs the disease may remain clinically silent for many months or years. Lameness may appear suddenly or insidiously. Often the condition occurs in both elbows and so signs may relate to joint stiffness in both forelimbs. Later in life, the osteoarthritis initiated by elbow dysplasia may progress to cause pain, stiffness and lameness.

How are these conditions diagnosed?

A clinical examination by a veterinary surgeon is the first step in diagnosis. If elbow dysplasia is suspected, radiographs (x-rays) are the most usual initial step in making a diagnosis. Although some forms of elbow dysplasia may be obvious on radiographs, often there are only subtle changes, particularly early in the disease. The radiograph below is typical for a young dog with fragmented coronoid process - the fragment cannot be seen on the radiograph but the secondary arthritis causes new bone formation at the margins of the joint and this can be detected. However, radiographs only give limited information and a much more accurate assessment can be made with arthroscopy. This involves placing a small endoscope, linked to a video camera and monitor, in to the joint to examine the interior in a key-hole manner. The picture below shows an arthroscopic view of a fragmented coronoid process. Arthroscopy also provides the opportunity to remove the fragment in a minimally-invasive manner. At Liverpool we have excellent facilities for arthroscopy of canine elbow joints.

What can be done to treat the condition?

If causing persistent problems, fragmentation of the coronoid process is, in our opinion, best treated with arthroscopy. Removal of the fragment can relieve pain and allow improvement in joint function. OCD can be treated in a similar manner. Treatment of ununited anconeal process is more complicated but currently repair of the fragment with a corrective osteotomy below the elbow appears to offer the best option.