Hip Dysplasia

Hip dysplasia is a common orthopaedic problem of dogs, especially medium to giant breeds. It occurs due to abnormal development and growth of the hip joint in the puppy. Both hips are usually affected, but only one side may show symptoms, and the onset of clinical signs (pain or lameness) may not occur on both sides at the same time.

Hip dysplasia is manifest early in life by varying degrees of laxity of the muscles and ligaments around the hip joint, which results in instability and malformation of the joint components. Arthritis is the long-term consequence of undetected or untreated hip dysplasia, due to the wear and tear which affects the joint surfaces as a result of the laxity.

The clinical signs of hip dysplasia are hind limb lameness, hind limb stiffness, bunny hopping, reluctance to lie down, sit, or get up, reluctance to go upstairs or jump onto things (e.g. into the car boot), and tiring on a walk. These signs are seen in puppies from around 6 to 18 months of age, or adult dogs 3–6 years of age. Investigation involves clinical examination, followed by sedation for hip X-rays or CT scan, and hip manipulation to test the degree of laxity and conformation.

Several treatment options are available, both surgical and non-surgical:

• Non-surgical treatment — often the sensible option for dogs that are only mildly affected, involving controlled exercise, swimming, non-steroidal anti-inflammatory medication and nutraceuticals, and weight management. Up to 70% of puppies with hip dysplasia respond to this management regime and are never bad enough to need surgery even as adults.
• Total Hip Replacement (THR) — the gold standard procedure for re-gaining as near normal hip function as possible, producing excellent results for pain-free hip function, though it is relatively expensive and there is potential for serious complications.
• Triple Pelvic Osteotomy (TPO or DPO) — a re-alignment procedure only suitable for young dogs (usually 6 to 9 months of age) that have not yet developed arthritic changes. Many puppies don't meet the strict inclusion criteria, and the outcome can be unpredictable and sometimes disappointing; as such it has fallen out of favour, with THR the preferred option.
• Juvenile Pubic Symphysodesis (JPS) — a much simpler and cheaper procedure that re-aligns the hip as the puppy grows, but can only be done in young puppies (4–5 months of age); it is not possible for most dogs as they are not diagnosed until later.
• Femoral Head and Neck Excision Arthroplasty (FHEA) — a salvage procedure done when all other options are not possible or have failed. The outcome is usually very good and acceptable, but full recovery can take time, hip function is never normal, and outcome can sometimes be unpredictable.

Prognosis with non-surgical management is good in many cases — up to 70% of puppies with hip dysplasia respond to conservative management and are never bad enough to need surgery even when they are adults. It is widely accepted that in dogs with hip dysplasia, arthritis progresses more quickly in overweight dogs.

Where surgery is needed, Total Hip Replacement is the gold standard for regaining as near normal hip function as possible and produces excellent results for pain-free hip function. Deciding which treatment is best is not always easy and requires careful assessment and discussion on a case-by-case basis.