Neochondrogenesis in free intra-articular, periosteal, and perichondrial autografts in horses.

This research study conducted on horses investigates the effects of different types of autografts (tissue transplanted from one location to another on the same individual) on the production of chondroid tissue (a precursor to cartilage). The findings suggest that the procedure led to visible new cartilage formation, especially in periosteal autografts.

Methodology

• The researchers collected periosteal autografts (the periosteum is a layer covering the bone, rich in stem cells and growth factors) from the tibia (shin bone), and perichondrial autografts (perichondrium is a connective tissue that surrounds the cartilage) from the sternum (breastbone) of six young horses.
• Each autograft was placed as a loose body into one tarsocrural joint (equivalent to the human ankle joint) in each horse under arthroscopic visualization (using a small camera to visualize the surgical area).
• The horses were encouraged to walk daily for a total of six hours each week for eight weeks following the procedure.
• Eight weeks after implantation, radiographs (X-rays) were taken of each graft site to examine mineralization (hardening), after which the grafts were surgically removed and examined for viability, size, and production of chondroid tissue.

Findings

• All autografts seemed viable and most had clear evidence of growth.
• Perichondrial autografts had a greater axis value, cross-sectional area, and perimeter than periosteal autografts in three horses, but the difference was statistically insignificant.
• New cartilage formation (neochondrogenesis) was observed in five out of six periosteal grafts and in one of six perichondrial grafts.
• Significantly more chondroid tissue was produced in periosteal autografts than in the one perichondrial graft where cartilage formation occurred. This chondroid tissue also displayed properties similar to those of typical cartilage.

Conclusion

• The study suggests that the use of periosteal autografts may be more effective for new cartilage formation than perichondrial autografts in horses.
• The viability and growth observed in both types of autografts indicate their potential usefulness in treatments necessitating cartilage regeneration or repair.