Definition

Hip Dysplasia is a developmental disorder of the canine hip joint which is strongly influenced by inherited and environmental factors.  It can cause SPONTANEOUS hind limb lameness in a proportion of affected dogs.  The condition is often bilateral although lameness may only be seen in one leg.  Giant, large and medium sized breeds are most commonly affected although the problem can be recognised in small breeds.

What Happens

The normal canine joint is a tight articulation between the head of the thigh bone (femur) and the deep socket in the pelvis (acetabulum).  The femur head should sit within the acetabulum so that more than 50% of its surface is snugly contained.  HIP DYSPLASIA describes malformed joints which are loose fitting (lax).  This laxity results in an unstable gait, and the femur head rubs unevenly against the rim of the pelvic socket.  The joint cartilage is then subject to excessive "wear and tear" and the joint capsule lining becomes inflamed and painful.  These processes result in deformity of the bones and arthritis develops.

Clinical Signs

One of the main problems in detecting Hip Dysplasia is the surprising but well known fact that some dogs with abnormal joints don't show any lameness and apparently walk with a normal gait.
Lameness is only apparent if the joint is sufficiently unstable or painful to enforce a change in gait and may relate to the age of the dog as well as the severity of the condition.  Potentially dysplastic hips are probably normal at birth but deteriorate as the animal grows.  Signs of lameness appear as the puppy becomes more active.  They do not move as freely as normal dogs and often "bunny hop" when trotting - as this allows them to shift weight off the painful hind leg on to the forelegs.  They prefer to sit rather than stand and have difficulty with stairs.  At the walk they may have a marked sway and the pelvis appears to rise and fall with each step.  Puppies suffering from severe dysplasia may not be able to move faster than a painful walking pace.

Hip Dysplasia progresses significantly between 6 and 18 months of age with most of the changes developing before 2 years old.  In adult dogs the changes that began early in life may result in hip arthritis in middle or old age.  The dog will then become lame even though no signs were noticed when it was a puppy.

Causes

Genetic and environmental factors influence the development of Hip Dysplasia and affect the final degree of lameness and disability.  The environmental factors of most importance are :-

1.    Feeding a diet that results in excessively heavy puppies at a young age.  This
       leads to overloading of the soft cartilage of the developing joint and a resulting
       deformation of the predisposed dysplastic joint.

2.    Over exercise of dogs with unstable joints will exacerbate any wear and tear of
       the hip.

Treatment

Various methods of treatment are available for Hip Dysplasia nowadays.  Rest and anti-inflammatory drugs will often help dogs showing pain after exercise.  Lead walks which are short but frequent - 10 minutes 4 times a day - will allow the growing skeleton to adapt and the joint to become more stable and pain free by the time the dog becomes mature at about 15 months of age.  This is greatly helped by keeping the dog slim and not allowing it to grow too fast.  The success off such conservative treatment is about 60 - 70% and the dog can then be allowed to become more active.

Dogs with severe signs that do not respond may need corrective surgery which may take many forms.  In young dogs realignment of the hip joint components can be performed by cutting the bones and adjusting them with steel plates and screws.  For older dogs a total hip joint replacement in which the femur head and acetabulum are replaced by a stainless steel prosthesis which fits into a plastic socket can be performed.  These operations are costly and may have to be carried out at veterinary referral centres.

Confirmation of Hip Dysplasia is diagnosed through x-rays carried out by your vet which are then sent to be assessed by a board set up by the British Veterinary Association and the Kennel Club who will give the dog what's called a Hip Score.
The lower the score the better (in the case of the GSD the consensus seems to be a "combined" score of 19).  Dogs with a higher score should not be bred from.

The BVA/KC hip scoring scheme has been set up to monitor the status of dogs joints with the aim hopefully, with the co-operation of both breeders and you the general public, to reduce the amount of dogs suffering this crippling disease. You can help by only buying from breeders who have bred from proven, lower scoring dogs as it's no use having a wonderful dog with a low score being mated with a higher scored dog or worse still, a dog that hasn't been scored at all !  It may also be an idea, even if you have no intentions of breeding your dog to have the dog hip scored so that the results can be recorded.  This way they'll be more and more dogs registered from all walks of life instead of results submitted by the same breeders over and over again.

If you have got your dog with the intention of breeding, even if it's only one litter then please *do* have the dog scored as well as having the other relevant tests carried out before even considering a mating.  Should a high hip score result come back then please, I urge you, do not breed from your dog as you could be adding to the misery of this condition when the pups come along.
Unfortunately, it has to be mentioned that there have been incidence's of pups developing Hip Dysplasia having been bred from lower scoring parents but these are in the minority.

Things may not be as bleak as they seem as some dogs with frighteningly high scores can still lead a full and active life style, running about having a ball, indeed we have a local Shepherd with a hip score of 97 who is still full of life and bouncing about!
There is now a wide range of treatments available whether it be corrective surgery, western medicine or alternative medicine so there is a good chance something will work for your dog.
I know of dogs that have responded to alternative therapies including Homeopathy, Magnetic Therapy and Acupuncture.
I also know a dog called Jezz who has had not one but two hip replacements carried out at Bristol University.  It was a long recovery as she wasn't allowed off her lead for at least 6 weeks, couldn't go up and down stairs and had to be lifted in and out of the car but it was all worth it as she's now on a decent diet, has shed a lot of weight and is now enjoying life again.  Her life began at 7 years old.