후방십자인대의 내측윤활주름 : 자기공명영상과 해부학 및 조직학적 고찰

Abstract

Purpose The purposes of our study were to analyze MRI and cadaveric findings concerning the medial synovial fold of the posterior cruciate ligament (PCL) and to classify the types of fold according to anatomic location.

Materials and methods Two musculoskeletal radiologists reviewed MR images of 17 cadaveric knees to classify the types of medial fold of the PCL by consensus. The MRI types were divided into three groups. In the type A, there was no definitive medial fold, and in the type B, inferior-short type, there was a small protrusion of the medial border. And type C, inferior-long type had a long enough fold to exceed the imaginary line, which is connecting between the medial tibial condyle and posterolateral aspect of the medial femoral condyle. Correlations were sought between the findings derived from the MRI studies and cadaveric dissections. Histologic analyses of the medial fold were also performed.

Results On MRI, the most common type of medial fold was the type B, 76.4% (n=13), followed by the type C, 11.8% (n=2), and the type A, 11.8% (n=2). In the cadaveric investigation, the medial folds of both the B and C types were found to project into the medial femorotibial joint. Moreover, there was also a protruding medial fold at the superior aspect of the PCL in the type A. Histologic examination of the medial folds revealed collagenous tissue surrounded by synovial cells.

Conclusions Medial folds of the PCL are normal synovial structures that can be seen by MRI and in cadaveric studies in a large proportion of the population.