The hip scoring scheme was established in the UK in 1965 to reduce the incidence and severity of hip dysplasia in the UK. Essentially it involves assessing an X-ray of a dogs hips taken before breeding takes place. The hip is a ball and socket joint and the better the fit, the lower the score. Scores are then compared to the average (median) for that particular breed aiming to breed from dogs with as low a score as possible.
Dogs with poorer hip scores have a greater degree of Hip dysplasia, because the joint is a poorer fit than it should be this leads to greater wear and damage to the joint and progression to painful arthritis later in life. It can be challenging to manage and from a veterinary point of view if it can be avoided it can lead to a much happier and healthier life.
Whilst many people are aware of the scheme and know to ask if the parents have been scored, it is also important to check what the scores were. For example the median for a Labrador Retriever is 9 according to the 2018 figures, so in line with the recommendations from the British Veterinary association (BVA) only dogs with a score less than 9 should be used for breeding.
If a breeder did wish to breed from a dog with slightly worse than average scores, because for example they had many other outstanding traits, then the advice would be only to pair with a dog with significantly better than average hip scores.
In summary check the scores, not just whether they have been done and if in doubt phone us up for advice before purchase. Further information can be found on the BVA website at https://www.bva.co.uk/canine-health-schemes/hip-scheme/. If you are looking to purchase a puppy, consider using the Puppy Contract (https://puppycontract.org.uk/).
There are further health schemes for elbows, eyes and other genetic tests, further information for which can also be found on the BVA website, and also the Kennel Club website.