Veterinary advice should be sought from your local veterinarian before applying any treatment or vaccine. Not sure who to use? Look up veterinarians who specialize in poultry using our directory listing. Find me a Vet

Tibial Dyschondroplasia


Dyschondroplasia is a skeletal bone disorder that occurs commonly in larger "meat-type" chicken breeds (often known as "broilers"). When it involves the tibiotarsus ('tibia') bone (the most commonly affected bone), the disorder is referred to as tibial dyschondroplasia (TD). The most common clinical sign is an abnormal gait leading to lameness.
Tibial dyschondroplasia
TD involves the development of an abnormal mass of cartilage at the growth plate of the long bones (the tibia) of the leg. Instead of calcifying, the cartilage remains soft and will often bend backwards under pressure or heavy body weight. As a result, chickens with TD often suffer from spontaneous leg fractures, necrosis, and severe pain and lameness. Birds with severe lameness are often unable to stand due to the pain. These birds will require special supportive care and will need to be relocated, otherwise they will be unable to access food or water---leading to starvation and death. If left with other birds they might also be subject to bullying from other flock members.

How Tibial Dyschondroplasia is Diagnosed

Radiographs taken of the tibiotarsus bone in birds with TD will show an abnormally large area of cartilage at the affected physis.

Clinical Signs

Abnormal gait
Frequently laying down
Reluctance to stand
Decreased movement


  • History
  • Clinical signs
  • Physical exam
  • Radiography


Supportive careProvide a therapeutic support device, such as a sling, chicken wheelchair, etc. to help take some of the pressure off of their legs.
Balanced diet and correction of any nutritional deficiencies.



Try to provide therapeutic support (chicken wheelchair, sling, or other device) during growth and likely for their entire lives, to minimize weight exerted on their legs.

Scientific References

Age Range

is most common in young, rapidly growing male broiler chicks between 3 and 8 weeks of age.

Risk Factors

  • Mycotoxin-contaminated feed
  • Fast-growing chicken breeds
  • Unbalanced diet consisting of too little calcium and too much phosphorus