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581 out of 12,930 evaluations of
German Shorthaired Pointer hip x-rays are dysplastic
according the OFA website. Results through 2007.
Hip Dysplasia is a terrible
genetic disease because of the various degrees of arthritis (also
called degenerative joint disease, arthrosis, osteoarthrosis) it
can eventually produce, leading to pain and debilitation.
The very first step in the
development of arthritis is articular cartilage (the type of
cartilage lining the joint) damage due to the inherited bad
biomechanics of an abnormally developed hip joint. Traumatic
articular fracture through the joint surface is another way
cartilage is damaged. With cartilage damage, lots of degradative
enzymes are released into the joint. These enzymes degrade and
decrease the synthesis of important constituent molecules that
form hyaline cartilage called proteoglycans. This causes the
cartilage to lose its thickness and elasticity, which are
important in absorbing mechanical loads placed across the joint
during movement. Eventually, more debris and enzymes spill into
the joint fluid and destroy molecules called glycosaminoglycan and
hyaluronate which are important precursors that form the cartilage
proteoglycans. The joint's lubrication and ability to block
inflammatory cells are lost and the debris-tainted joint fluid
loses its ability to properly nourish the cartilage through
impairment of nutrient-waste exchange across the joint cartilage
cells. The damage then spreads to the synovial membrane lining the
joint capsule and more degradative enzymes and inflammatory cells
stream into the joint. Full thickness loss of cartilage allows the
synovial fluid to contact nerve endings in the subchondral bone,
resulting in pain. In an attempt to stabilize the joint to
decrease the pain, the animal's body produces new bone at the
edges of the joint surface, joint capsule, ligament and muscle
attachments (bone spurs). The joint capsule also eventually
thickens and the joint's range of motion decreases.
No one can predict when or even
if a dysplastic dog will start showing clinical signs of lameness
due to pain. There are multiple environmental factors such as
caloric intake, level of exercise, and weather that can affect the
severity of clinical signs and phenotypic expression (radiographic
changes). There is no rhyme or reason to the severity of
radiographic changes correlated with the clinical findings. There
are a number of dysplastic dogs with severe arthritis that run,
jump, and play as if nothing is wrong and some dogs with barely
any arthritic radiographic changes that are severely lame.
If
you would like to submit a hip x-ray of your GSP as an example,
please send jpg and the sex of the animal, grade and report date to
haffner1@mindspring.com
Understanding
the OFA Hip Dysplasia Number:
Example: LR-100E24M-PI
-
LR
= Breed Code, in this case a Labrador Retriever
-
100
= Ascending numerical identifier given to each animal within a
breed evaluated as normal and given a number, in this case the
100th Labrador to be given a number
-
E
= The phenotypic OFA evaluation, in this case E = Excellent,
other normal phenotypes include G (Good) and F (Fair).
-
24
= The age in months when the testing was done, in this case 24
months
-
M
= Sex, in this case a male
- PI
or VPI = Indicates that the animal has been
permanently identified in the form of tattoo or microchip. If
the dog is permanently identified AND the id has been verified
and signed off by the attending veterinarian, a suffix of VPI
is applied. If the animals lacks permanent identification, a
suffix of NOPI is applied.
HELPFUL
LINKS ON HIP DYSPLASIA
Orthopedic
Foundation for Animals - http://www.offa.org/hipinfo.html
Are
breeders winning the battle with Hip Dysplasia? - http://www.labbies.com/dysp2.htm
Example
Hip x-rays, Good Positioning, Environmental Factors - http://leerburg.com/pdf/hipplacementforxrays.pdf
(ebook)
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