Hip and Elbow Dysplasia
What is dysplasia?
Almost certainly you would have heard of hip dysplasia in large breed dogs, and unfortunately the labrador is no exception. Whilst the labrador is generally healthy and well-constructed, with strong well-proportioned bodies, hip and elbow dysplasia can occur.
Two known factors determine whether hip dysplasia will occur and if so, how bad it will be. These are hereditary (genetic) and environmental influences. It is important you have knowledge about dysplasia, so that you are fully informed, can interpret your puppy’s parent’s hip and elbow scores, and understand disposition to dysplasia.
Dysplasia presents in dogs as instability of the hip joint (or elbow joint). In a normal hip, the femur is connected to the hip joint with the head of the femur (ball) sitting in the acetabulum (socket). In dogs who develop dysplasia, the ‘ball’ doesn’t fit as well in the socket as it should, resulting in joint laxity (looseness). Because the ligaments become overstretched by the looseness (causing the ball and socket to grind against one another rather than sliding smoothly), the joint attempts to re-establish stability by laying down new bone, creating spurs and scar tissue. This, coupled with the degeneration of cartilage (wear from rubbing), is what eventually causes lameness and painful osteoarthritis of the joint.
Several influences lead to development of dysplasia in dogs. A genetic predisposition can be amplified by environmental factors, such as excessive growth, over-exercise, being overweight, improper nutrition, disruption of hormones (such as spaying a dog too early before fully sexually mature), inappropriate or overly-excited activity, repetitive stair climbing, and jumping down from objects.
These are the ‘outside’ influences that alter and shape the growth and functions of the bones, cartilage, ligaments, tendons, and muscles of the body. We carefully explain environmental prevention in our puppy pack.
Hip dysplasia results in inflammation and pain, and may cause a range of observable signs such as changes in gait, lameness, stiffness after rest, exercise intolerance and noticeable pain (in those dogs more severely affected).
Screening for Dysplasia
The Australian National Kennel Council manages a scheme to reduce hip and elbow dysplasia in registered purebred dogs. Under CHEDS (Canine Hip and Elbow Dysplasia Scheme), breeders are required to have their dogs’ hips and elbows tested and ‘scored’. This is an expensive screening ($600-900 per dog) requirement, but very necessary. The joints are xrayed by a veterinarian, the images are analysed, and a ‘score’ is determined by one of the accredited radiologists on the ANKC-approved panel. Results are submitted and registered with the ANKC.
Each aspect of the hip joint is scored between 0 and 6. Hip scores range from 0:0 (0), to the highest possible score of 53:53 (106). Each hip joint is scored individually between 0 and 53 and a total score is reported, such as: 5:9 (14). This means the Right hip scored 5, the Left hip scored 9, totalling 14 combined.
A perfect hip score would be 0:0 (0) but, very few labradors (or any large breed) will have this score. A slight irregularity in the ball or socket may give a score of 2:3 (5), this would be considered very good hips. The more irregular the ball and socket becomes, the higher the resulting score. A lower score means better hips.
Not only do we have hip and elbow scoring done, we also study the genetics and bloodlines of previous generations and combine this knowledge with our scores and assessment of our dogs’ conformation and structure, to determine which bloodlines will produce the best puppies, with proper structure and good health. Many, many hours of research and analysing goes into this aspect of breeding.
Whilst the breeder makes every effort to minimise dysplasia through screening, assessing genetics, and analysing bloodlines, it cannot be guaranteed that your puppy will not develop dysplasia. Since environmental influences have been proven to play a significant role in whether or not a puppy later develops dysplasia. And you, the new puppy owner, owes a responsibility to your pup to help minimise his chance of developing dysplasia by controlling the environmental influences. Following exercise guidelines, feeding a healthy diet, not allowing your labrador to become overweight, and supervising his type and level of activity, is your role in preventing dysplasia.