Development of a three-dimensional computer model of the canine pelvic limb including cruciate ligaments to simulate movement

Biomechanical Evaluation of a Novel Ceramic Implant for Canine Cranial Cruciate Ligament Rupture Treatment: A Finite Element Analysis Approach

This research investigates the biomechanical effects of a novel ceramic implant for the treatment of canine cranial cruciate ligament rupture (CCLR) based on the tibial tuberosity advancement (TTA) method using finite element analysis (FEA). A 3D FEA of the tibiofemoral joint simulating the applied forces (44.5% of body weight) during the mid-stance phase (joint angle 135°) of the dog's stride was performed. Three conditions were considered for each joint: the physiological condition, the pathological condition with CCLR and the restored condition after TTA. Eight cadavers were used to create fifteen paired knee joints. The results showed significant differences in the forces that could be measured in the patellar tendon (PT) and in the cranial displacement of the tibial tuberosity between the conditions. The PT forces increased in the pathological state and continued to increase in the restored state, while the cranial displacement of the tibial tuberosity increased in the pathological state and decreased again in the restored state. Correlation analyses revealed significant correlations between PT forces, body weight and cranial displacement. The FEA provides initial insights into the force distribution and functionality of the ceramic implant. However, further testing is required to validate reliability and evaluate the efficacy of the implant.

Estimation of footprints of the canine stifle ligaments using deformable shape templates of bones

Knowledge regarding the ligament footprints in the canine stifle is essential for biomechanical modeling of the joint and patient-specific surgical planning for anatomical ligament reconstruction. The present study aimed to establish and evaluate deformable shape templates (DSTs) of the femur and tibia with footprints of the cruciate and collateral ligaments embedded for the noninvasive estimation of ligament footprint positions. To this end, a data set of computed tomography (CT)-derived surface models of the femur and tibia were established and used to build statistical shape models (SSMs). The contours of the stifle ligaments were obtained from CT scans of 27 hindlimb specimens with radio-opaque markings on the ligament footprints. The DST, constructed by embedding averaged footprint contours into the SSM, was used to estimate subject-specific ligament footprints in a leave-one-out cross-validation framework. The DST predictions were compared with those derived from radio-opaque-marked footprints. The results showed that the averaged Euclidean distances between the estimated and reference footprint centroids were less than 1.2 mm for the cruciate ligaments and 2.0 mm for the collateral ligaments. The DST appeared to provide a feasible alternative approach for noninvasively estimating the footprints of the stifle ligaments in vivo.