In-vivo Morphometric Study of the Cruciate Ligaments of the Knee Joint

Introduction: since the in vivo morphometric data about the ACL and PCL are scarce, we aimed to study their length, thickness and angle by using the MRI. Material and Methods: the present study included 34 MRI images of the knee joints. The length and thickness were measured in sagittal section T1 weighted and T2 weighted images of the 1.5 Tesla MRI. The angles were measured by using the coronal section of the MRI images. The online software, RadiAnt DICOM viewer was used to perform the measurements. Results: the mean length of the ACL and PCL was 36.8 ± 4 mm and 39 ± 4 mm respectively. The thickness of the ACL at the femoral end, midpoint and tibial end were 12.4 ± 1.7 mm, 6.8 ± 0.9 mm and 13.2 ± 1.8 mm respectively. The thickness of the PCL at the same topographical location was 8.2 ± 1.2 mm, 4.8 ± 0.9 mm and 8.1 ± 0.8 mm respectively. The ACL coronal tibial angle, Blumensaat angle and PCL angle were 60.2 ± 4.8°, 11.5 ± 2.7° and 128.8 ± 9.2 ° respectively. Conclusion: the present study has provided novel information about the length, thickness and angle of the cruciate ligaments in Indians, which can be used to establish standard dimensions of the normal ACL and PCL as an aid to arthroscopic surgeries of the knee joint.