Orientation changes in the cruciate ligaments of the knee during skeletal growth: A porcine model

Abstract

Musculoskeletal injuries in pediatric patients are on the rise, including significant increases in anterior cruciate ligament (ACL) injuries. Previous studies have found major anatomical changes during skeletal growth in the soft tissues of the knee. Specifically, the ACL and the posterior cruciate ligament (PCL) change in their relative orientation to the tibial plateau throughout growth. In order to develop age-specific treatments for ACL injuries, the purpose of this study was to characterize orientation changes in the cruciate ligaments of the Yorkshire pig, a common pre-clinical model, during skeletal growth in order to verify the applicability of this model for pediatric musculoskeletal studies. Hind limbs were isolated from female Yorkshire pigs ranging in age from newborn to late adolescence, and were then imaged using high field strength magnetic resonance imaging. Orientation changes were quantified from the magnetic resonance images using image segmentation software. Statistically significant increases were found in the coronal and sagittal angles of the ACL relative to the tibial plateau during pre-adolescent growth. Additional changes were observed in the PCL angle, Blumensaat angle, intercondylar roof angle, and the aspect ratio of the intercondylar notch. Only the sagittal angle of the ACL relative to the tibial plateau experienced statistically significant changes through late adolescence. The age-dependent properties of the ACL and PCL in the female pig mirrored results found in female human patients, suggesting that the porcine model may provide a pre-clinical platform to study the cruciate ligaments during skeletal growth.

Development of a pre-clinical experimental simulation model of the natural porcine knee with appropriate ligamentous constraints

“…Porcine knees were chosen because their joint size, joint loading, cartilage and trabecular bone thickness more closely match the human condition than alternative animal models [22]. Due to this anatomical similarity, the porcine knee model has previously been widely used in studying human knee joint disease such as ligament disorders [23, 24] and new treatments such as a novel meniscus repair technique [25]. Since our study was focused on methodology development, using a porcine knee model was an important step prior to investigating a human knee model.…”

Large Animal Models for Anterior Cruciate Ligament Research

“…A study by Cone et al evaluated the angle between the porcine ACL and the tibial plateau in growing pigs, demonstrating an increasing angle in the sagittal plane throughout late adolescence (34). The magnitude of this angle increase in pigs (30°) is somewhat larger than is observed in human adolescents (20° increase), suggesting that pigs may have a steeper tibial plateau angle than humans, similar to other quadrupeds (34, 35). The pig has a wide tibial plateau, similar to the sheep, with the width being most similar to humans in overall size (3).…”

Sex-Specific Function and Morphology of the Anterior Cruciate Ligament During Skeletal Growth in a Porcine Model

“…Data from female specimens has been previously reported. [22][23][24] was not certified by peer review) is the author/funder. All rights reserved.…”

“…Our group and others have used the porcine model to study the skeletally immature ACL [22][23][24][25][26][27] and sex-specific ACL behavior. 28; 29 The porcine model is widely used for musculoskeletal applications 30 and is a good model to study function of the mature ACL.…”