Growth Plates

Growth plates (epiphyseal plates) are cartilaginous zones between the ends of bones and the shafts of long tubular bones. They enable longitudinal bone growth and are particularly susceptible to injury during development. In puppies and young dogs, they play a central role in the healthy development of the locomotor system.

Anatomy and Function

Growth plates consist of cartilage tissue, which is gradually converted into bone (ossification) during development. As long as the plates are open, the bones can continue to grow in length. Once the plates ossify, longitudinal growth is complete.

Closure of Growth Plates

The timing of closure varies depending on the bone region, breed and size of the dog:

• Small breeds: usually completed by 8–12 months
• Medium breeds: approx. 12–15 months
• Large and giant breeds: up to 18–24 months

Example: The ulna often closes earlier, whereas plates in the shoulder or thigh area may remain open longer.

Risks with Open Growth Plates

As long as the plates are not closed, they are sensitive to mechanical stress:

• Fractures in the area of the growth plates can lead to misalignments.
• Overexertion (e.g. through intense jumping or excessive stair climbing) can impair growth.
• Inadequate nutrition with too much energy or calcium can lead to growth disorders and orthopaedic diseases (e.g. OCD, HD).

Clinical Significance

Veterinarians assess the closure status of growth plates using X-rays. This is particularly important in cases of orthopaedic problems, planned surgeries (e.g., skeletal corrections) or for assessing growth.

Tips for Dog Owners

• Do not overexert young dogs; avoid long bike rides, excessive ball throwing or jumping.
• Promote sufficient but age-appropriate exercise (walks, free play on soft surfaces).
• Choose balanced nutrition for puppies and young dogs, specifically tailored to the breed size.
• Always have lameness or pain checked by a vet.

Conclusion

Growth plates are crucial for healthy bone growth in dogs. As long as they are open, load, exercise and nutrition must be carefully adjusted to avoid damage. Only after complete closure is the locomotor system stable and able to bear load.