Diffuse intrasubstance signal abnormalities of the posterior cruciate ligament: the counterpart of the mucoid degeneration of the anterior cruciate ligament? A case series.

In this report seven cases of diffusely altered signal intensity of the posterior cruciate ligament (PCL) at magnetic resonance imaging (MRI) are described. The abnormalities resemble those of mucoid degeneration of the anterior cruciate ligament (ACL) and are associated with it in six cases. Although mucoid degeneration of the ACL is an increasingly reported entity, with well-established imaging criteria at MRI, to the authors' knowledge similar findings were never described before for the PCL. It is hypothesized that these abnormalities of the cruciate ligaments are similar in nature, probably related to degenerative changes of the connective tissue.