What is total hip replacement?
Total hip replacement (THR) is an advanced surgical procedure that removes the ball and socket parts of the hip joint and replaces them with metal and plastic implants. Often recommended for animals with advanced osteoarthritis or hip dysplasia, the goal of hip replacement surgery is to improve your pet’s quality of life, offering them pain relief and allowing them to maintain an active lifestyle.
When is total hip replacement needed?
Total hip replacement is offered for animals that struggle with painful hip conditions, and will only be recommended if other surgical techniques or rehabilitation methods have failed to manage your pet’s pain. Because hip dysplasia is most common in large dog breeds, total hip replacement (THR) is most commonly performed in these breeds. However, the condition can also affect cats and small dogs who can also benefit greatly from hip replacement.
Not all patients with hip dysplasia are candidates for a THR. Those with mild pain and lameness may be managed with conservative management. A total hip replacement would only be suggested and performed in the benefits outweighed the risks, as with all major procedures, it doesn’t come without possible risks and complications. THR can be performed in patients from around 10 months of age and there is no upper age limit.
Other indications for THR include dislocated (luxated) hips, hip fractures and avascular necrosis of the femoral head (Legge Perthe’s disease).
What are the types of total hip replacement?
THR surgery replaces a dysfunctional, painful hip joint with an artificial prosthesis, to provide a fully functional, pain-free joint. The prosthesis replaces both the ball and socket of the joint and there are a variety of options of implants available.
The surgery is performed through a small incision directly over the hip, and involves removing the degenerated femoral head (ball) and acetabulum (socket), replacing them with artificial components. The implants can be attached to the bone using cement or through a cementless system, depending on which best suits your pet. The cementless system relies on bone ingrowth into the implant for permanent fixation: the prostheses are secured by a “press-fit”, meaning that the bone in contact with the prostheses can grow into the small pores in their surface. Cementless THRs are not made for medium and small dogs or cats.
What does hip replacement surgery involve?
Dogs and cats have to be evaluated to see if they are suitable for total hip replacement surgery. This is often done on a separate day, prior to the surgery, here at Swift Referrals. By obtaining very specific X-rays of the pelvis and (femur) and placing them against templates of the various sizes of prostheses available, we can measure the correct size of prostheses for the patient and order them if necessary.
On the day of surgery, a team of two Surgeons and Nurses will be involved in performing the joint replacement. The operation is performed through a relatively small incision directly over the hip. Careful preparation of the hip socket (acetabulum) and top of the femur is necessary prior to placement of the relevant cemented or cementless prostheses. The two artificial components are then brought together (reduced) and the stability of the hip checked. The thick capsule that surrounds the joint is carefully sutured prior to closure of the rest of the muscle and skin.
Radiographs are obtained at the end of the operation to check the position of the prostheses.
It is likely your pet will stay in hospital for the first couple of days for intravenous pain relief and to ensure they are weight bearing on the operated leg. Post-op care and rehabilitation following THR surgery is very important and can take many months. Painkillers, antibiotics and an Elizabethan collar will be provided at discharge. The first check up is usually back at your own Vets around 10 days after surgery, at which point, any skin sutures can be removed.
Exercise must be restricted and your pet kept in a puppy crate or pen for the first few weeks until the joint capsule and surrounding soft tissues heal. They can only be taken out to the toilet on a lead or harness initially and you will be provided with an exercise regime to follow thereafter. It is imperative that your dog is not allowed to climb stairs or jump onto furniture.
After six weeks, your pet would revisit Swift Referrals for post-operative radiographs to ensure that the implants are stable and in the correct position. At this stage, further advice will be given with regards to exercise.
We then recommend a clinical examination and repeat X-rays one year after THR surgery, and annually thereafter. You must comply with this requirement to be eligible for the lifetime warranty.
What are the risks?
Fortunately, the success rate for total hip replacement surgery is very high, with over 95% of animals having excellent limb function after recovery. However, as with any major surgery, there are possible complications. The most common problem is dislocation of the prosthesis, which may require a second operation.
Although a long and complicated procedure, total hip replacement has the potential to provide your pet with a pain-free, normal hip joint, allowing them to return to a happy and active lifestyle.
The success rate of total hip replacement surgery in dogs and cats is high, and the majority do very well after their operation. It is a major undertaking and not a decision that would be taken lightly, but the procedure is one which our surgeons commonly perform. THR can be completely life changing for a dog or cat. They are radically transformed into happy, comfortable patients, able to exercise again and they have a vastly improved quality of life, for you to be able to enjoy with them.