Legg Calve Perthes Disease
in Small Breed Dogs

By Janice Jones   |   Former Veterinary Technician

Medically reviewed and updated: January 2026

Legg-Calvé-Perthes disease (often shortened to Legg-Perthes) is an orthopedic condition that primarily affects young, small-breed dogs. It causes pain and lameness in the hip due to a loss of blood supply to the femoral head.

Although the diagnosis can be frightening for owners, the outlook for most dogs is very good, especially when the condition is identified early and treated appropriately.

This page explains what causes Legg-Calvé-Perthes disease, which dogs are most at risk, how it is diagnosed, and what treatment and recovery typically involve.

Causes of the Disorder

The hip is a ball-and-socket joint. The “ball” is the head of the femur (thigh bone), and the “socket” is part of the pelvis.

Legg-Calvé-Perthes disease occurs when blood flow to the femoral head is disrupted. Without an adequate blood supply, bone tissue begins to weaken and die, leading to deformity of the femoral head and deterioration of the hip joint.

As the joint becomes unstable, affected dogs experience increasing pain, lameness, and reduced use of the leg. Over time, muscle loss may occur in the affected limb.

The exact cause of the disrupted blood supply is not fully understood. The condition is believed to have a genetic component, and trauma may contribute in some cases. Because of this suspected inherited risk, dogs diagnosed with Legg-Calvé-Perthes disease should not be bred.

The condition most commonly appears between 4 and 12 months of age and usually affects only one hip, though bilateral cases can occur.

Background on Legg Calve Perthes Disease

You might also see it called Perthes Disease, Legg–Perthes Disease, or Legg–Calve-Perthes Disease (LCPD)—all are referring to this degenerative disease of the young.

Other names that it goes by are “avascular necrosis of the femoral head” and “aseptic necrosis of the femoral head."

Whatever you decide to call it, it means pain for your small breed dog.

It was named after the physicians, Arthur Legg an American Orthopedic Surgeon, Jacques Calvé French Orthopedic Surgeon, and Georg Perthes, a German Orthopedic Surgeon who were responsible for identifying the disease.

According to OFA (Orthopedic Foundation for Animals),

the following breeds are at risk for Legg-Calve-Perthes-Disease:

Affenpinscher
Australian Terrier
Bichon Frisé
Border Terrier
Boston Terrier
Cairn Terrier
Chihuahua
Cocker Spaniel

Dachshund
Fox Terrier
Jack Russell Terrier
Lakeland Terrier
Manchester Terrier
Miniature Pinscher
Miniature Schnauzer
Pomeranian
Pekingese

Poodle
Pug
Schipperke
Scottish Terrier
Shetland Sheepdog
Silky Terrier
Welsh Terrier
West Highland White Terrier
Yorkshire Terrier

Legg-Calvé-Perthes disease is seen most often in small and toy breeds, particularly terriers and certain companion breeds.

Symptoms of
Legg Calve Perthes Disease

Early signs of Legg-Calvé-Perthes disease are often subtle and may be mistaken for a minor injury.

Common symptoms include:

• Limping or lameness in one hind leg
• Reluctance to put weight on the affected hip
• Pain when the hip is touched or manipulated
• Decreased activity or playfulness
• Crying or vocalizing when moving
• Muscle loss in the affected leg over time

Symptoms usually worsen gradually as the joint continues to deteriorate.

Diagnosis 

Diagnosis begins with a physical examination and is confirmed with X-rays of the hip. Imaging allows the veterinarian to evaluate changes to the femoral head and rule out other causes of lameness.

Treatment

Initial management may include rest and pain control, but in most cases, surgery is recommended to provide long-term relief.

The most common procedure is a femoral head ostectomy (FHO), in which the damaged portion of the femur is removed. Over time, scar tissue forms a functional “false joint” that allows comfortable movement without bone-on-bone pain.

When performed early and followed by proper rehabilitation, the prognosis after surgery is generally excellent.

Daily Living with the Condition

Dogs usually make a full recovery after surgery providing that the owners stick with the rehabilitation recommendations.  It often takes between three and six months for complete recovery.

Regular exercise, physical therapy and diet management are three aspects of recovery.  Veterinarians also prefer to see their patients about every two weeks to assure that they are making progress.

According to Dr. Daniel A. Degner, Board-certified Veterinary Surgeon, activity should not be limited after surgery.  Rather, it is recommended. 

Exercise helps the hip joint stay mobile and prevents adhesion from forming.  Swimming,  depending on the breed is a good exercise, but professional physical therapy services should be used where ever possible.

Some vets will provide anti-inflammatory medications to help the dog move and prevent swelling and the accompanying pain.

Prognosis and Quality of Life

Most dogs diagnosed with Legg-Calvé-Perthes disease go on to live full, active lives after treatment. Small dogs, in particular, tend to recover very well following surgery when rehabilitation guidelines are followed.

Early diagnosis, appropriate surgical care, and consistent physical therapy play key roles in long-term success.

References and Further Reading

https://www.ofa.org/diseases/other-diseases/legg-calve-perthes

https://www.embracepetinsurance.com/health/legg-perthes-disease

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1695790/