Abstract
The purpose of this study was to investigate the remodeling process of the devascularized anterior cruciate ligament (ACL) in the dog. In the first group, the ACL was devascularized by rubbing its surface and removing the synovial sheath. The devascularized ACL was observed at one and six weeks postoperatively with microangiography, hydrogen washout technique and histology. In the second group, the ACL was isolated with both femoral and tibial attachments in a bone-ligament-bone fashion, and reduced and fixed. Then, the ACL was reconstructed with an autogeneous ACL graft. The same methods of observation were used as in the first group. Five knees were used in both groups at each of the two time periods. In all knees, vascularization of the operated-on ACL recovered rapidly. The blood flow of the ACL at one week was about 80% of that of the normal control, and extrinsic revascularization was observed along the full length of it in microangiography. At six weeks, the revascularization became more pronounced. Histologically, there was no cell death and minimal remodeling process. Similar trends were observed both in microangiography and histology. This revascularization and remodeling process after devascularization was different from that reported for the patellar tendon used in ACL reconstruction. Therefore it is speculated that the main nutrient pathway of the ACL is diffusion from the synovial fluid, and so a difference in biological property exists between the ACL and the patellar tendon.
