In Vivo Evaluation of Electrospun Polycaprolactone Graft for Anterior Cruciate Ligament Engineering

The anterior cruciate ligament (ACL) is critical for the structural stability of the knee and its injury often requires surgical intervention. Because current reconstruction methods using autograft or allograft tissue suffer from donor-site morbidity and limited supply, there has been emerging interest in the use of bioengineered materials as a platform for ligament reconstruction. Here, we report the use of electrospun polycaprolactone (PCL) scaffolds as a candidate platform for ACL reconstruction in an in vivo rodent model. Electrospun PCL was fabricated and laser cut to facilitate induction of cells and collagen deposition and used to reconstruct the rat ACL. Histological analysis at 2, 6, and 12 weeks postimplantation revealed biological integration, minimal immune response, and the gradual infiltration of collagen in both the bone tunnel and intra-articular regions of the scaffold. Biomechanical testing demonstrated that the PCL graft failure load and stiffness at 12 weeks postimplantation (13.27 +/- 4.20N, 15.98 +/- 5.03 N/mm) increased compared to time zero testing (3.95 +/- 0.33N, 1.95 +/- 0.35 N/mm). Taken together, these results suggest that electrospun PCL serves as a biocompatible graft for ACL reconstruction with the capacity to facilitate collagen deposition.