Cadaveric study of the secondary medial patellar restraints: patellotibial and patellomeniscal ligaments.

PURPOSE: To detail the anatomy of the medial patella stabilizers, medial patellotibial (MPTL), and medial patellomeniscal ligaments (MPML), focusing on the points of origin and insertion, length, thickness, width, and fibres orientation to study the frequency of anatomical variations and the anatomy of these ligaments, thereby improving surgical techniques.

METHODS: Thirty dissected knees were analysed. A digital caliper was used to measure the length, thickness, and width, as well as the mid-point of the ligaments insertion and the distance from the MPTL insertion to the articular surface of the tibia. The angle of inclination of the ligaments was calculated in the coronal plane. The collected data were tabulated and statistically analysed.

RESULTS: MPTL was present in 90 % as a visible thickening of the deep medial retinaculum and exhibiting only one anatomical variation. The MPML was absent in one of the dissected knees, and one anatomical variation was found. The tilt angle of the ligaments was very similar, with an average of 22.2° ± 7.6° for the MPTL and 24.2° ± 6.6° for the MPML.

CONCLUSION: The MPTL is a long visible structure of the deep layer of the medial retinaculum, but with a distinct origin and insertion. The MPML is thicker with an angular direction similar to MPTL. The presence of these ligaments in most of the specimens studied suggests that the real anatomical and biomechanical importance of these ligaments should be further investigated because they play a role in the patellar stability.