Hip Dysplasia mainly affects large and giant breeds, however medium dogs can be affected and smaller and toy breeds are rarely affected. There are some factors that can cause hip dysplasia, such as genetics, too much weight on the hindquarters at a young age, too much exercise, nutrition, amount fed/ growth rate can all play a part in determining the outcome of a dogs hips. When deciding to own a large breed it is important to know the history of the parents and grandparents of that dog.

The genetic link

If a dog is from a lineage of dogs that have suffered hip dysplasia, particularly the dam and sire, there is a high risk that the offspring will suffer from the disease. If both the dam and sire have hip dysplasia, the approximate percentage of the offspring developing hip dysplasia is 75%, the remaining 25% may have good hips,( this figure is approximate & may be higher in individual cases) in simpler terms and for example purposes only, if a bitch suffering HD whelps a litter of 4, bred with a dog who also suffers HD approximately 3 or more puppies may develop hip dysplasia and 1 will show no clinical signs, however, that one puppy may pass on the disease to his/her offspring. The offspring in these circumstances may have a 75% chance or more of showing no clinical signs of hip dysplasia, with possibly 25% or more having hip dysplasia. With careful selection and breeding, the occurance of hip dysplasia can be eliminated, however you must bare in mind that this does not affect the breeds prone to developing the disease.

German Shepherds and other large/giant breeds may develop hip dysplasia if they are allowed to gain too much weight or grow too rapidly, this is due to excess weight being carried which puts strain on the growing muscle and connective tissue,they are not strong enough to support the excessive weight gain, this then produces a loose joint which is the onset of hip dysplasia, rapid growth rate also has the same effects,the muscle doesn’t mature at the rate of skeletal growth resulting in a loose,unstable joint.

Other contributing factors include a high calorie diet, which produces obesity/ rapid weight gain, an improper balance of calcium and phosphorus which is bad for young, growing dogs bone development, excessive weight applied on the hind legs during bone growth such as playing games which allows the dog to jump on the hind legs or standing at a window to look out, or jumping up at visitors in excitement etc, too much exercise at a young age as well as walking on a hard surface such as a pavement instead of grass can also play a part in the development of hip dysplasia.

dogs that are genetically susceptible

For dogs that have a high risk of developing hip dysplasia, there are a few guidelines you can follow, it is advised that any dog susceptible to develop HD that their exercise is limited and they are confined to cage rest with minimal exercise, and food intake should not be freely given, set meal times of the required amount and proper veterinary guidelines should be followed.

hip dysplasia defined

Hip dysplasia is the main cause of lameness affecting the rear limbs in dogs. clinical signs can be seen in a dog as early as 4 months old,it develops due to the looseness (laxity) of the muscles, ligaments and connective tissue that support the joint and keeps it functioning properly.As the laxity develops the femoral head (the ball)and the acetabulum (the socket) loose contact with each other, this is termed subluxation. This looseness creates the abnormal wear of the bones reshaping the bones.



above is a normal joint structure, you will see the ball and socket joint fit together in quite a snug comfortable fit and the gap between the femoral head (ball) and the pelvic socket are quite close, this is an ideal joint.




above is the x-ray of a dog that suffers degenerative disease as a result of hip dysplasia, you will notice some changes to the right side , the bones are no longer round and no longer fit together tightly, the socket is quite shallow and the femoral head is quite rigid.




above is an x-ray of advanced hip dysplasia, this dog now suffers osteoarthritis as a result.


signs of hip dysplasia

The dog may be reluctant to exercise, may show pain when getting up from a lying position,run with a bunny-hopping gait, may show pain or stiffness in the back leg(s) after exercise or after a period of rest such as waking up after sleeping all night, limping and being unable to get up the stairs is also another sign.

Diagnosis

diagnosis is confirmed ultimately with x-rays, however, the presence of arthritis and full examination is also included, some dogs don’t show any signs until later in life when arthritis is evident and pain develops.

Treatment

Treatment depends on severity, it can be limited to rest and pain medication, or may include a change in diet to reduce excess weight, exercise may be included in the treatment as this not only helps dog with excessive weight, certain exercise can help strengthen the muscles that have become loose, swimming, walking or treadmills, or jogging can help build up the muscles (this is not the same for every dog) the wrong exercise for the wrong stage of dysplasia can be more harmful than good, anti-inflammatory drugs may be prescribed, surgery may also be an option and supplements such as glucosamine may be helpful, corticosteroids may also be prescribed, each case is different, speak to your vet about which treatment is best for your dog.

surgery

If the dog is aged between 16 and 20 weeks a procedure called Juvenile Pubic Symphysiodesis can be performed, it reduces the liklihood of osteoarthritis,by changing the angle of the hips, this is achieved by fusing two bones together.It must be performed prior to arthritic development.

Femoral Head and Neck Excision involves removing the femoral head and a fibrous pseudo-joint replaces the hip, in most cases the dog does not experience pain, however full mobility is not reached but will allow the dog to be more active than before surgery. It is considered when total hip replacement is not an option or the cost of total hip replacement surgery cannot be provided by the owner, the procedure can be performed on large dogs however the recommended weight for surgery is 40LBS.

Total hip replacement This procedure is considered for patients with chronic hip dysplasia, along with the resulting degenerative disease, it involves replacing the entire joint with an artificial joint, a dog must be at an age where the bones are mature and have stopped growing. Post surgery recovery the dog will return to an almost normal active life without pain.

Triple Pelvic Osteotomy (TPO) This procedure is generally performed on young dogs that are less than 10 months old and have severe laxity,without joint damage, it involves breaking the pelvic bones to realign the pelvic socket and femoral head and correcting subluxation, the outcome of this surgery is very successful although it’s expensive.