What is hip dysplasia?
Hip dysplasia is a deformity of the hips that occurs as your dog grows during puppyhood and commonly affects large breed and giant breed dogs.
The hip is what we call a ‘ball-and-socket joint’. For the joint to work well, the ‘ball’ (or head of the femur/thigh bone) and the ‘socket’ (or acetabulum of the pelvis) need to sit together securely. This joint sits within a tough fibrous joint capsule and contains a joint fluid lubricant to help reduce friction during movement. Additionally, the surface of where the bones meet is also covered by a smooth cartilage.
Photo by My Vet Animal Hospital
Hip dysplasia occurs where the growth of the ‘ball’ and ‘socket’ do NOT grow at equal rates during puppyhood. This discrepancy in growth rate results in laxity (looseness) of the joint often due to either too shallow or flattened of a ‘socket’ or a malformed ‘ball’. As the body attempts to stabilise the joint, there will be progressive loss of cartilage and formation of bony spurs (osteophytes) and scar tissue. This eventual degeneration results in early degenerative joint disease (DJD) or osteoarthritis (OA).
The most common breeds at risk of hip dysplasia are often the large and giant breed dogs, including:
- German Shepherds
- Golden Retrievers
- Labrador Retrievers
- American Staffordshire Terriers
- Saint Bernards
However, hip dysplasia can affect any breed including smaller-to-medium sized breeds such as:
- French Bulldogs
- Pembroke Welsh Corgi
What are the signs that I should watch out for?
- Weakness and pain in the hind legs
- Abnormal gait – waddle, hopping, swaying of the hips
- Abnormal posture – elevated pelvis, low head position and hunched/arched back to shift body weight to the forelimbs
- Grinding or grating (crepitus) feeling associated with rotation of the hip joint
- Lack of coordination and/or an abnormal gait
- Reluctance to move or stand up
- Wastage of muscle in the hind legs
- Pain on palpation of the hip flexor muscles (e.g. iliopsoas muscles)
How do you diagnose hip dysplasia?
Early intervention is crucial for the management of hip dysplasia. If your dog is showing any clinical signs of hip dysplasia or is a breed that is at-risk, it is important to have a chat with your vet who may then recommend some testing for diagnosis.
1) Hip x-rays: Hip dysplasia is best diagnosed through radiographic x-rays of the hips, as it will allow us to determine the severity of the disease and any degenerative osteoarthritic changes that may already be present. The best diagnostic x-rays are performed when your dog is both completely still and relaxed, so this will usually require either deep sedation or anaesthesia.
Occasionally, some objective measurements may be performed to help assess the severity of the hip dysplasia such as the Norberg angle. A Norberg angle of about 105° is considered to be excellent hips. A Norberg angle closer to 90° is indicative of hip dysplasia.
Chart by Mark Flückiger
2) Ortolani sign – While they are under deep sedation or anaesthesia, additional physical examination tests may be performed such as palpating for the Ortolani sign. This is where pressure is applied and the hip is moved in such a way that if the joint is loose, the femoral head ‘ball’ will be heard and felt as a ‘clunk’ in and out of the ‘socket’.
How do you treat hip dysplasia?
The treatment of hip dysplasia is dependent on severity and can vary from non-surgical management (including nutrition, supplements, physiotherapy, etc.) to surgical management. We will often recommend dogs with hip dysplasia to have an orthopedic specialist consultation for further evaluation and to discuss available options.
1) Nutrition: Nutrition can play a significant role in the development of hip dysplasia, especially in large breed puppies who are growing rapidly. Large breed puppies should only eat diets designed for them to ensure they grow at a slower but steady pace. They should not grow too quickly as this can lead to bones and muscles growing at different rates, predisposing them to joint diseases like hip dysplasia.
2) Weight loss: Heavier body weight means more pressure on the joints, which can exacerbate clinical signs of hip dysplasia. Therefore it is important to maintain your dog at a healthy weight and consult with your vet to determine how much your dog should weigh and whether a weight loss program will need to be commenced.
3) Exercise and physiotherapy: It is important to modify your dog’s exercise habits and encourage low-impact activities to reduce pressure on the joints. This could include short, regular walks to keep your dog mobile, but avoid long periods of strenuous exercise with lots of running and jumping. Another great low-impact exercise that is gentle on the joints is swimming. Physiotherapy can also be very valuable in performing repetitive targeted exercises to strengthen the relevant muscle groups to help support movement of the hip joint.
4) Joint supplements and anti-inflammatory pain relief medications: There are many different types of drugs that can be used to aid in both the repair of damaged cartilage as well as prevention of cartilage damage. These include injections (such as Zydax), supplements (such as 4cyte epiitalis forte gel), and special diets (such as Hill’s metabolic & mobility). Your vet will advise you on which is the most suitable for your pet and advise on extra pain relief if required.
5) Surgery: There are multiple surgical procedures (including juvenile public symphysiodesis, triple pelvic osteotomy, femoral head ostectomy, and total hip replacement) that can be performed to help correct hip dysplasia. The type of surgical procedure is dependent on a number of factors including the age of your puppy at diagnosis and the severity of their hip dysplasia. Your vet may recommend an assessment with a specialist orthopedic surgeon to which may be the best procedure for your dog.
If you suspect your dog has hip dysplasia or you have a breed that is at risk, please do not hesitate to give us a call on 8484 2020 and book a vet consultation to examine your pet and discuss a plan of action.