What Is Canine Hip Dysplasia?
Canine hip dysplasia is a common skeletal condition, especially in large or giant breed dogs, although it can occur in smaller breeds, as well. In order to understand how the disease works, owners first need to understand the basic anatomy of the hip joint.
The hip joint functions as a ball and socket. In dogs with hip dysplasia, this joint fails to develop properly, rubbing and grinding instead of sliding smoothly. This results in deterioration over time and an eventual loss of function of the joint itself.
What Causes Hip Dysplasia in Dogs?
There are several factors that lead to the development of hip dysplasia in dogs, beginning with genetics. Hip dysplasia can be hereditary and is especially common in large and giant breed dogs, This genetic predisposition can be amplified by environmental factors, such as excessive growth, exercise, your dog’s weight, and your dog’s nutrition.
Large and giant breed puppies have special nutrition requirements and need specially formulated large-breed puppy foods. These foods help prevent excessive growth, which can lead to skeletal disorders like hip dysplasia, along with elbow dysplasia, and other joint conditions. Slowing down these breeds’ growth allows their joints to develop without putting too much strain on them, helping to prevent problems down the line. Keep in mind, hip dysplasia is not limited to large or giant dog breeds.
Improper nutrition can also influence a dog’s likelihood of developing hip dysplasia, as can too much exercise – or too little. Obesity puts a lot of stress on your dog’s joints, which can exacerbate a pre-existing condition like hip dysplasia or even cause hip dysplasia.
Recent results from research funded by the AKC Canine Health Foundation have the potential to significantly impact recommendations for spaying and neutering dogs in the United States. Most dogs in the United States are spayed or neutered, and for years the procedures have been completed prior to maturity. The study, published in the prominent, open-access journal PLOS One, suggests that veterinarians should be more cautious about the age at which they spay and neuter in order to protect the overall health of dogs.
A team of researchers led by Dr. Benjamin L. Hart at the University of California, Davis has completed the most detailed study performed to date that evaluates the incidence of cancer diagnoses and joint problems in one breed -- Golden Retrievers -- by neuter status: early (before 12 months old), late (12 months or older), and intact. Consistent with previous studies on the topic, the results showed an increased likelihood of hemangiosarcoma, lymphoma, mast cell tumors, and canine cruciate ligament (CCL) rupture in neutered dogs.
The most profound observations were in hip dysplasia in male dogs when comparing early and late neutering. The risk of development of hip dysplasia doubles, and the disease occurs at a younger age in the early-neuter group compared to both the intact and late-neuter groups. No occurrence of CCL disease was observed in intact male or intact female dogs, or in late-neutered females. In early-neutered dogs, the incidence of CCL was 5.1 percent in males and 7.7 percent in females, suggesting that neutering prior to sexual maturity significantly increases a dog’s risk of developing CCL disease. With respect to cancer, cases of lymphoma were 3-fold greater in the early-neutered males.
Sex hormones have a massive impact on the development of the skeletal system. Think of growth spurts in puberty, for example. And these conditions are all associated with suboptimal bone alignment in joints, resulting in unusual wear or movement of the joint. So, it’s perfectly reasonable that by preventing the dog’s normal puberty from completing, we are altering the way these joints form.
Spaying or neutering before 6 months, which is common practice in the US, interrupts the production of sex hormones and delays the closure of at least some of the bony plates. Some or all of the bones will grow beyond their genetically determined length, leaving the bones comprising the hip joint mismatched in length. Early spay/neuter significantly increases the occurrence of hip dysplasia.