What is hip dysplasia?
Hip dysplasia is one of the most common orthopedic condition in dogs. The canine hip joint is a ball-and-socket arrangement. In a dog with hip dysplasia, this joint doesn’t develop properly and ends up rubbing and grinding instead of sliding smoothly. Though most common in large and giant-breed dogs, it can also affect smaller breeds.
The word “dysplasia” means “abnormality of development”. Hip dysplasia is a canine genetic condition in which there is a tendency towards development of hip laxity early in life. Hip dysplasia is not congenital because affected dogs are born with morphologically normal hips.
The soft tissues (ligaments and joint capsule) that normally stabilise the hip joint become loose within the first few weeks of life. The consequence of this laxity is that the normally very congruent ‘ball and socket’ hip joint becomes much less congruent. The ball becomes flattened and deformed and the socket becomes more saucer-shaped. All dogs with hip dysplasia develop secondary osteoarthritis of the affected joint. The vast majority of affected dogs have dysplasia of both hips.
What is the cause of hip dysplasia in dogs?
There are many contributing factors that can lead to hip dysplasia, with the headlining factor being genetics. Breeds like the Labrador, German Shepherd, and Great Dane are commonly affected, though responsible breeders can screen for the condition before selecting an animal for breeding. Excessive growth, a problem that commonly affects larger breeds, places a significant strain on joints that have not yet fully developed can also lead to hip dysplasia.
Large and giant breed puppies need to be fed foods that have been specially formulated to meet their nutritional needs and help control the excessive growth that can cause hip dysplasia and a number of other joint disorders. This is why a delayed spay or neuter procedure or an entirely different sterilization tactic is often used for these breeds.
Next, diet and exercise can also play a part. Improper diet and insufficient exercise can lead to obesity, which places additional strain on your pet’s joints.
Signs of Hip Dysplasia in dogs
Hip dysplasia can cause a significant amount of pain for our furry friends, and watching your much-loved pooch battle the discomfort of this degenerative condition can be quite distressing. One of the first signs many owners notice is decreased activity levels from their pet. Whereas once your dog may have been eager to get up and go at every opportunity, now they prefer to sleep or rest and show much less enthusiasm to go for a run or get active.
More specifically, you may notice that your pet has increasing difficulty jumping or climbing stairs. The hind legs are obviously essential to your dog’s ability to perform these everyday tasks, so the reduced range of motion within the joint and the accompanying pain of the condition may show in your pet’s movements. Your dog may also have difficulty rising from a lying position – especially first thing in the morning when they’re still getting “warmed up”.
Another common symptom to keep an eye out for is known as “bunny hopping”. This is when an affected dog lifts both their hind legs simultaneously, similar to what a rabbit does when jumping, in an effort to reduce pain. Along with hind limb lameness, pain, or sensitivity around the hips, and a narrow stance, it’s a warning sign that shouldn’t be ignored.
How is hip dysplasia diagnosed in dogs?
Hip dysplasia is usually diagnosed after a pet owner notices their dog exhibiting some or all of the following clinical signs:
- Exercise intolerance
- Difficulty rising, sitting or lying
- Difficulty climbing stairs or getting in and out of the car
- Abnormal gait – Sometimes described as a ‘swaying’ gait during walk
- Limping on one or both hind limbs
- Protective of hip region during grooming or bathing
- Pain – not necessarily in all dogs
- Bunny hopping
- Narrow stance
- Loss of thigh muscle mass
Your vet may have recognized an abnormal gait or noticed hip pain in your dog during routine health checks or following concerns raised by you. If your veterinarian has a suspicion of hip dysplasia, they may perform radiographs (x-rays) of your dogs hip joints.
It may also be advised that your dog has additional diagnostic imaging such as CT or MRI which will be performed by one of our veterinarians. Following diagnostic imaging and complete clinical examination, your veterinarian will be able to advise you of the treatment options suitable for your dog.
How is hip dysplasia treated in dogs?
If your dog is showing any signs or symptoms of hip dysplasia, take them to the vet for a check-up. Your veterinarian will perform a physical exam and test the flexibility of the joint, and then take some X-Rays to determine the exact nature of the problem and its severity.
The good news is that there are several treatment options available, and they range from some simple lifestyle changes right through to surgery. Weight loss and reduced exercise can take the strain off your dog’s hips, while physical therapy (for example swimming) can help improve their mobility.
A range of anti-inflammatory medications can also be given, and joint fluid modifiers can enhance joint health. If surgery is recommended there are several potential courses of action.
The most common surgeries are:
- Double or triple pelvic osteotomy (DPO/TPO) – which involves cutting the pelvic bone to improve joint function.
- Femoral head and neck ostectomy (FHO) – which sees the “ball” of the hip joint cut off and reduces pain.
- Total hip replacement (THR) – which uses metal and plastic implants to eliminate most discomfort and return hip function closer to a normal level.
- Juvenile pubic symphysiodesis (JPS) – which induces premature fusion of the pelvis in order to alter growth so the ball part of the ‘ball-and-socket’ hip joint is improved.
Non-surgical management of hip dysplasia in dogs
Non-surgical management is recommended in dogs that are diagnosed with hip dysplasia as an incidental finding. For clinically affected dogs, the likelihood of a good response to non-surgical management depends on how severe the hip pain is.
The cornerstones of non-surgical treatment are body weight management, physiotherapy, exercise modification, and medication (anti-inflammatory pain killers). In the short term, most dogs will make an improvement when they are managed appropriately.
At the Animal Clinic of Billings and Animal Surgery Clinic, we are able to provide you and your dog with a rehabilitation plan for hip dysplasia. This is coordinated through our rehabilitation service with one of our canine rehabilitation therapy practitioners.
Upon scheduling an appointment with one of our PRT practitioners, a thorough clinical examination will be performed and a rehabilitation plan will be uniquely designed for your dog’s individual needs including a home exercise plan for you to follow at home.
Most appointments are attended as an out-patient and your Physical Rehabilitation Therapy Practitioner will regularly evaluate your dog’s progress and amend your home exercise plan as necessary.
Surgical management of hip dysplasia in dogs
Surgical treatments are divided into procedures that modify the hip anatomy and procedures that are considered salvage surgeries.
This surgery involves induced premature fusion of part of the pelvis, in order to alter growth such that location of the ball part of the ‘ball-and-socket’ hip joint is improved. This is a simple surgery that involves electrical cauterization of part of the pubis (on the underside of the pelvis).
In order to be effective, dogs must be a maximum of 5 months of age and must have mild-to-moderate laxity confirmed using manipulative and radiographic tests. As most dogs do not develop clinical signs until they are at least 6 months old, JPS is usually a prophylactic surgery. All dogs treated by JPS must be neutered at the same time.
This surgery involves the surgical modification of the existing hip joint to improve capture of the ball by the existing socket. Three cuts are created in the bones around the cup and the free segment thus created is rotated to a point that allows optimal hip capture. The bone segments are fixed in their new position using a custom plate and screws.
Healing of the bone takes approximately 4-6 weeks. TPO is only effective in dogs that have hip laxity and no secondary remodelling of the bones or subsequent osteoarthritis. Suitable dogs are most often clinically immature and arthroscopic examination of the joint is recommended to check for cartilage damage before surgery is performed.
In a DPO, two cuts are made in the bone and the pelvis is rotated slightly to create a better angle for femur positioning. The bones are also secured with the use of specialty plates and screws.
Total Hip Replacement is an advanced surgical procedure that involves cutting out the whole of the diseased hip joint. The “ball” is replaced with a metal implant, and the “socket” is replaced with a plastic and metal implant. Although most of the dogs we treat with THR are larger dogs, we are also able to perform the surgery in small dogs. The success rate for THR is approximately 90-95%, and most dogs are more comfortable within a few days of surgery. Many patients will return to full levels of activity.
This operation is a salvage procedure usually only considered in cases where THR cannot be performed. In this technique, the femoral head and neck (the “ball” part of the joint) are completely removed allowing a “false joint” to form. Pain is relieved by elimination of bony contact between the ball and the edge of the socket, but the resulting “false joint” is typically limited in its function, so clinical outcome may be unpredictable, particularly in larger dogs. Intensive physical therapy is mandatory after FHNE or FHO surgery.