Revascularization of a Human Anterior Cruciate Ligament Graft During the First Two Years of Implantation

Abstract

The blood supplies of 45 unimpinged, human anterior cruciate ligament grafts were studied during the first 2 years of implantation. Grafts were defined as un impinged by the low signal intensity of the graft ob served on a sagittal proton density magnetic resonance scan. Magnetic resonance imaging with the intravenous contrast agent gadolinium diethylenetriamine pentace tic acid was used to evaluate the blood supply of the hamstring autograft as well as the periligamentous tis sues by assessment of enhancement patterns after ad ministration of the agent. The unimpinged anterior cru ciate ligament graft acquired no discernible blood supply during the 2 years of implantation. The graft re tained the same hypovascular appearance as the nor mal posterior cruciate ligament. In contrast, the periligamentous soft tissues were richly vascularized and covered the graft by 1 month. The viability of an un impinged, human anterior cruciate ligament graft may de pend more on synovial diffusion than on revascularization.