Total Hip Replacement

Why choose Anderson Moores for your pet's THR?

With a technical surgery such as a total hip replacement (THR) it is critical to have a good surgeon who is very familiar with the procedure. This is not a surgery that should be performed by the 'occasional' surgeon. There are plenty of studies that show that less experienced surgeons have more complications.  At Anderson Moores, our hip replacement surgeries are carefully planned and carried out by our board-certified specialist surgeons who work together as a team to ensure the best possible outcome for your pet. We have the highest standards of aseptic technique (sterility) in our operating theatres to ensure the risk to your patient is minimised. Something that can only be achieved in a specialist hospital.

History

The first hip replacements in dogs were what is known as 'cemented' total hip replacements (THR), meaning that the implants (the cup in the acetabulum of the pelvis and the stem in the femur) were held in place using an acrylic cement, known as bone cement. These have been very successful and are still very commonly performed in people and dogs however they do have some drawbacks. Over the last decade or so 'cementless' hip replacement has become increasingly popular in dogs. Rather than using cement to hold the implants in place, these systems rely on the friction created by a ‘press-fit’ between the bone and the implant. Cementless implants have a porous surface to encourage bone to grow into the implant over time. Avoiding the use of cement reduces the amount of implanted foreign material thus reducing the infection risk. The implants may also last longer as particulate matter generated from the cement is a factor in implant loosening.  Finally, implant revision, if necessary, is more straight-forward.

Cementless total hip replacement systems are available for most medium- and large-breed dogs and over recent years, smaller cementless implants have been developed to minimise the requirement for cement in our smaller patients. Total hip replacement is also a great option for the smallest of dogs and even cats with hip disease or hip fractures. In these smaller patients cemented total hip replacement is performed.

The Biomedtrix cementless THR system is the most widely used system in the world with over 54,000 dog hips having been replaced using this system. It uses a 'press-fit' femoral stem and acetabular cup that achieve initial stability with the friction of the electron-beam melted titanium implant. Long term stability comes from bone ingrowth directly into the implants. The implants are constantly being updated and improved with the latest generation of acetabular cups having liners that are highly cross linked and impregnated with vitamin E, changes which have been shown to reduce long-term wear.

So what cases are suitable for THR?

THR is generally reserved for dogs with significant and persistent symptoms attributable to hip disease, most commonly hip dysplasia/osteoarthritis but occasionally for certain fractures.

Surgery is not appropriate for dogs with radiographic (x-ray) evidence of hip disease that do not have any symptoms. Most patients are older than 10 months, but the system can be used in dogs as young as 7 months if required. Cemented THR is also an option for small dogs and cats with hip disease, avascular necrosis of the femoral head (Legg Perthes disease) or non-reconstructable hip fractures.

Total hip replacement is not appropriate for all dogs with hip disease or for all owners. Prior to surgery all patients are assessed clinically and radiographically. Long term management options, costs and the risks of surgery are always discussed with the owner in detail prior to committing to hip replacement. The nature of this type of surgery and the quality of the implants we use mean that total hip replacement is not a cheap option for your pet; and there are likely to be additional preoperative and postoperative costs. The costs involved are always discussed at the initial assessment. Alternative surgical options do exist if these costs are prohibitive, although other surgeries do not offer as full a return to function or comfort as total hip replacement.

To minimise the risk of complications it is very important to strictly rest your pet after THR surgery. This sample discharge sheet will give you an idea of what is involved.

Information sheets

Click here for further information on the Hip Registry

If your pet will be having a hip replacement it would be helpful if you could bring a completed Hip Registry consent form with you prior to the surgery:

Click here for the consent form

Click here for James' guide to Hip Dysplasia, published in 'Dogs Monthly' magazine October 2011 (thanks to Dogs Monthly for allowing this to be posted here www.dogsmonthly.co.uk)