REVASCULARIZATION OF A HUMAN ANTERIOR CRUCIATE LIGAMENT GRAFT DURING THE FIRST 2 YEARS OF IMPLANTATION

The blood supplies of 45 unimpinged, human anterior cruciate ligament grafts were studied during the first 2 years of implantation. Grafts w ere defined as unimpinged by the low signal intensity of the graft obs erved on a sagittal proton density magnetic resonance scan. Magnetic r esonance imaging with the intravenous contrast agent gadolinium diethy lenetriamine pentacetic acid was used to evaluate the blood supply of the hamstring autograft as well as the periligamentous tissues by asse ssment of enhancement patterns after administration of the agent. The unimpinged anterior cruciate ligament graft acquired no discernible bl ood supply during the 2 years of implantation. The graft retained the same hypovascular appearance as the normal posterior cruciate ligament . In contrast, the periligamentous soft tissues were richly vasculariz ed and covered the graft by 1 month. The viability of an unimpinged, h uman anterior cruciate ligament graft may depend more on synovial diff usion than on revascularization.