Total hip replacement (THR) has been performed in dogs for more than 40 years and the technique and implants have been evolving continuously over that time. In centres such as ours THR is now a very routine and predictable procedure with a low complication rate. A modern cementless THR performed by an experienced surgeon can be expected to last for life in the vast majority of patients. Because THR is now a very reliable and routine procedure, for most patients the criteria for surgery have changed. No longer is THR viewed as a ‘last resort’ treatment -quite the opposite in fact. These days the emphasis is on giving patients with hip pain the maximum period of benefit from a new hip. So when can or should THR be considered? It’s a question I get asked a lot and one I’ll dig into below.
1. The adult dog with hip dysplasia/osteoarthritis (HD/OA)
Traditional dogma was to delay surgery for as long as possible. For many patients this will be inappropriate. Not only do younger patients have lower complication rates, delayed surgery means the additional expense of non-surgical therapies (which come with their own risks) and a longer period of time before the patient gets the benefit of a pain-free hip. That is not to say that a non-surgical approach shouldn’t be tried initially, but that if this provides less than complete resolution of the issue then THR should be considered. Interestingly, a recent analysis of the financial cost of HD/OA presented at the 2025 Autumn BVOA meeting (Low D.) concluded that THR was more cost-effective than long-term medical management for canine hip dysplasia.
An initial non-surgical approach will include exercise modification (i.e. avoiding very energetic activities, reducing the length of walks), pain-killers (primarily NSAIDs) and physical therapy (physiotherapy/hydrotherapy). Owners will have different preferences for how long they pursue these strategies before seeking further advice or considering other options but THR should be considered for any patient with clinical signs despite these strategies, for dogs requiring long-term medication or long-term exercise restriction to manage their hip HD/OA or for dogs having frequent flare-ups of hip pain/lameness/stiffness due to hip OA.
What about Librela (bedinvetmab)? There is a growing awareness in the orthopaedic community that Librela can be associated with serious, potentially catastrophic, joint degeneration in some patients, and so we would not recommend Librela as a first-line treatment for OA. We would also not advocate Librela for patients for which surgery may be considered; subjectively the preoperative use of Librela seems to be associated with a higher risk of complications after joint replacement. I will generally request a patient is off Librela for at least three months, preferably longer, before performing joint replacement. These concerns also apply to cats and the use of Solensia (frunevetmab).
An important consideration when assessing a pet with HD/OA is that we are often not very good at detecting the signs of chronic pain in our pets and chronic hip pain can cause more than just lameness. A dog may be happy to run around and exercise but they may show subtle signs of hip pain after exercise. They may be stiff/sore when they get up from resting later in the day or the next day or they may be more grumpy/withdrawn. These changes can go unrecognised until the hip pain is resolved. It’s not unusual for owners to comment after THR that their dog seems happier/more playful/less grumpy, with owners often not having noticed these changes before surgery.
Age does of course influence decision-making. If a young dog has relatively minor symptoms, but significant HD/OA on x-rays, then I’m more likely to recommend surgery then an older dog with minor symptoms and similar looking hips. Osteoarthritis is a gradually progressive condition and that young dog has plenty of time to get worse, so why not give it a completely pain-free hip whilst it is young, will heal quickly and has many years ahead to enjoy its new hip?
I am often asked if there is an upper age limit to THR, and the short answer is there isn’t. As long as the patient is in relatively good health then THR remains an option. Clearly the risk:benefit ratio changes with advancing age. Older patients are at increased risk of complications because remodelling of the hip is likely to be more extreme and older patients tend to have poorer bone quality and delayed healing times. We can mitigate some of these risks, for example by plating the femur to reduce the risk of femoral fracture. The old patient that is coping well on medical management is however less likely to have surgery, although surgery is still an option for those that are not coping.
Weight management is an important part of the management of any OA patient but patients which are possible THR candidates should not have surgery delayed whilst weight-loss is attempted. Such patients will generally be inactive due to their hip disease and achieving weight-loss can be a very slow process. It is generally better to improve patient comfort and activity through THR and the weight-loss will then be far easier to achieve.
2. The puppy with hip dysplasia
Historically cemented THR would be delayed until skeletal maturity, i.e. 10-12 months of age. Cementless THR systems however allow us to perform THR younger than this. If young patients are very painful then surgery can potentially be performed from 6-7 months of age but if the pain can be adequately managed medically then I will wait until 9-10 months of age in most puppies. Some dogs with very severe hip dysplasia, where the hip is effectively luxated (known as luxoid hips), will benefit from earlier surgery and should be referred for assessment at the earliest opportunity. Delay can lead to acetabular bone loss and soft tissue changes which will make later surgery more complicated. When assessing immature dogs for possible hip dysplasia do remember to check for an Ortolani sign (https://tinyurl.com/dogortolani). Radiographs can provide a false-negative result for hip dysplasia in young patients, but a positive Ortolani sign means hip laxity is present and therefore confirms a diagnosis of hip dysplasia.
3. Smaller dogs and cats
Around a third of my THR case load is smaller patients and we now have cementless systems for these patients too. Smaller patients do amazingly well after THR and THR should be considered as an alternative option in any patient which might traditionally have been treated with femoral head and neck excision (FHNE/FHO). This includes for example young cats with chronic femoral neck fractures and young dogs with Legg-Perthes disease. Compared to FHNE, THR offers an immediate improvement in comfort (we expect THR patients to be walking well on the limb from day one after surgery) and a much quicker, more predictable and more complete recovery.
THR and FHNE both have pros and cons. Compared to femoral head and neck excision, the downsides to THR are the greater expense, the need for stricter aftercare and the risk of complications. After FHNE the primary concerns are a prolonged recovery period and poor limb function/persistent ‘hip’ pain.
The complication rate after THR is around 5-10%. Most of these can be successfully resolved with preservation of the THR but further surgery may be required to achieve this. In many centres this will mean considerable additional expense for the owner which can put an owner off considering THR in the first place. At The Moores Orthopaedic Clinic we are confident of our low complication rates and so for owner peace of mind we offer a surgical guarantee after THR (and other routine procedures).
The complication we worry about more than any other after THR is infection, since this can require implant removal to resolve it. It is therefore critical that THR surgery is performed in the right environment and with appropriate precautions. At The Moores Orthopaedic Clinic our infection rate is very low. In our first 100 THRs to date we have had one infection, in an older high-risk patient with other health issues. Our operating theatres were designed to human theatre specifications with HEPA filtered ventilation which is very rare in veterinary clinics (I don’t know of another clinic that has this). Having a team that is very familiar with the procedure is also important -this means short anaesthetic and surgical times which also reduces infection risk. And of course, as with any highly technical procedure, complication rates reduce with surgeon experience.
