Legg Calvé Perthes disease in dogs


  • Legg Calvé Perthes is a painful condition that causes the hip joint to crumble and collapse.
  • It affects young dogs and is most common in small breeds.
  • Legg Calvé Perthes can be treated with an operation to remove the diseased hip joint.
  • With successful treatment, the outlook for a dog with Legg Calvé Perthes is good.
  • Dogs that have had Legg Calvé Perthes shouldn’t be bred from, because the condition can be passed on to the puppies.

Click image to enlarge.

What is Legg Calvé Perthes Disease?

Legg Calvé Perthes is an uncommon painful condition that affects the hip. It’s also known as avascular or aseptic necrosis of the femoral head. The hip is a ‘ball and socket’ joint and in Legg Calvé Perthes disease, there is poor blood supply to the ‘ball’ part of the hip joint. This causes the bone to die and crumble and leads to a stiff, very painful hip joint. This causes your dog to limp and eventually have arthritis.

Legg Calvé Perthes often develops at around five months old and most commonly affects small breed dogs for example Yorkshire Terriers, Miniature Pinschers and Miniature Poodles. It usually only affects one hip.


Symptoms of Legg Calvé Perthes usually start at around five months of age and often include:

  • Limping and stiffness in one back leg that gets worse over time and may result in them not putting any weight at all on the affected leg. It’s possible but much less common for both back legs to be lame.
  • Shrinking leg muscles – the affected leg may look thinner because the leg isn’t being used properly.
  • Pain – that gets worse over time. You may notice your dog is more irritable if touched on or near the affected leg and they may be reluctant to jump on to surfaces or climb stairs.


Your vet will examine your dog’s back legs and hips. If they suspect Legg Calvé Perthes, they will need to take an X-ray of their hips, which is likely to be done under sedation or general anaesthetic.


Anti-inflammatory pain relief

Anti-inflammatory medicines don’t fix the problem, but will be given throughout treatment to reduce pain and inflammation to help keep your dog comfortable. They may also need other types of pain relief alongside.


  1. Your vet is likely to suggest an operation called a ‘femoral head and neck excision’ or ‘FHNE’. FHNE surgery involves removing the damaged section of hip bone. After it’s been removed, fibrous tissue fills the space and forms a ‘false’ joint. A false joint isn’t as flexible as a normal hip joint, but allows your dog to walk pain free and won’t usually affect their day to day movement.
  2. A hip replacement is an alternative treatment option for Legg Calvé Hip replacements are usually performed by specialist vets in referral practices.


Physiotherapy is extremely helpful after surgery to help your dog start using their leg again and to achieve the best possible outcome for your dog.


After surgery, you will need to help your dog recover. This will include medication and controlled exercise to make sure their false joint forms properly and becomes as flexible as possible.


With surgery, pain relief and physiotherapy, it’s likely that your dog will respond and recover well. Once their surgical wound has healed and their false hip has formed, they should be able to walk on the affected leg. Some dogs continue to limp once they have recovered but many dogs recover so well that it can be difficult to tell that they ever had a problem.

Without any treatment, your dog will suffer with a painful hip and arthritis.


We shouldn’t breed from dogs that have suffered from Legg-Perthes because it can be passed on to their puppies.

When to contact your vet

Contact your vet if you are concerned your dog may have Legg Calvé Perthes, or if they have developed a limp.

You know your dog best, always contact your vet if you’re concerned.


Treatment for Legg Calvé Perthes can become very expensive, so it’s important to speak openly with your vet about the cost of treatment, your finances, and what you think is right for your dog.

Consider taking out dog insurance as soon as you bring your dog home, before any signs of illness start. This will give you peace of mind that you have some financial support if they ever become unwell.


Is Legg Calve Perthes disease painful?

Yes, it is a painful disease that becomes more painful if left untreated.

Is Legg Calve Perthes disease hereditary in dogs?

Yes, the cause of the disease is unknown but it is inherited in some breeds.

Published: March 2024

Written by vets and vet nurses. This advice is for UK pets only. Illustrations by Samantha Elmhurst.