Veterinary advice should be sought before applying any treatment or vaccine.


Osteochondrosis (OC) is a developmental orthopedic disease (DOD) commonly diagnosed in growing horses. The disease is caused by abnormal cartilage development within one or more joints, resulting in lesion formation. The severity of the disease can range from mild to severe, however most cases require surgery to prevent further damage to the joints. The hind limb joints are most frequently affected.


Osteochondrosis occurs most frequently in Standardbreds, Warmbloods and Thoroughbreds. The prevalence of osteochondrosis in Dutch Warmbloods between 1-4 years old is estimated to be about 25% of the population. In Thoroughbreds, the overall prevalence is 23%. Researchers from the University of Illinois and the University of Minnesota identified several genetic mutations associated with OC in a population of yearling horses born and raised on a single breeding farm in the United States.

Probable Causes

A wide range of different factors have been proposed as potential causes of osteochondrosis in horses---occurring individually or more than likely, a combination of the following:
  • Nutrition
  • Genetic predisposition
  • Environmental factors
  • Acute or repeated trauma
  • Exercise program

Clinical Presentation

The presentation of osteochondrosis in horses differs depending on the site of involvement and on the stage of to which the syndrome has progressed.


Joint effusion
Reduced activity
Prolonged recumbency


  • History
  • Clinical signs
  • Physical exam
  • Radiographs
  • Ultrasound



SurgeryShould be considered for foals demonstrating clinical signs of joint effusion and lameness
TrainingLimiting exercise, combined with chondroprotective therapy



Based on the location, number of joints involved, lesion size, presence of osteoarthritis and severity of clinical signs.

Scientific Research

General Overviews

Age Range

OC tends to affect the joints of young, rapidly growing performance horses

Risk Factors

  • Poor conformation
  • Genetic predisposition
  • Excessive exercise or lack of adequate exercise in young foals
  • Rapid growth
  • Nutrition: Horses on diets exceeding the National Research Council (NRC) recommendations for carbohydrate and protein requirements.
  • Acute or repeated trauma: Biomechanical stress or trauma on the joints and growth cartilage.
  • Copper (trace element) deficiency