An animal model to study ACL reconstruction during growth

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Veterinary Science

Background:

• Treatment for anterior cruciate ligament (ACL) ruptures in skeletally immature individuals remains debated.
• Existing animal models often induce growth disturbances, limiting their applicability.
• A reliable model is needed to investigate ACL reconstruction during skeletal development.

Purpose of the Study:

• To establish and describe a large animal model for studying ACL reconstruction in skeletally immature sheep.
• To replicate ACL reconstruction in a growth-plate-sparing manner, avoiding iatrogenic growth disturbances.
• To provide a foundation for future histological and biomechanical investigations of ACL healing and graft incorporation during growth.

Main Methods:

• Skeletally immature sheep (4 months old) underwent transphyseal ACL reconstruction on the right knee.
• The contralateral knee served as a control.
• Animals were sacrificed at 3, 6, 12, and 24 weeks post-surgery for analysis.

Main Results:

• The study details the methodology for a novel ovine ACL reconstruction model.
• Basic science data are presented to validate the model's utility.
• The model successfully avoids inducing growth disturbances, a key criterion for human relevance.

Conclusions:

• This skeletally immature ovine model provides a reproducible platform for ACL reconstruction research during growth.
• The model facilitates further investigation into the histological and biomechanical outcomes of ACL repair in young patients.
• It enables addressing critical questions regarding optimal surgical techniques and biological responses in pediatric ACL injuries.