Significance of medial patello-femoral ligament in support of patella stability: features of anatomy and biomechanics

The purpose of the study - anatomical and biomechanical substantiation of medial patellofemoral ligament (MPFL) reconstruction in cases of recurrent patella dislocation. Material and methods. Anatomical studies were performed in 27 fresh frozen cadaver knees. Biomechanical study was made using video capture system with 5 specimens of the knee. In the first stage we examined the lateral displacement of the patella when the knee was flexing, and in the second - isometric properties of the MPFL. Results. In all cases MPFL was found between the knee capsule and the superficial fascia. In 6 (22.2%) cases singlebundle structure was revealed, in 14 (51.8%) - two-bundle and in 2 (7.4%) - three-bundle structure. In 2 (7.4%) knee joints MPFL was presented in one thinned bundle, attached to the upper third of the patella. The degree of the MPFL isometry was indicated by changing in the distance between the optical markers located in the regions of attachment of MPFL ligament. For all of the knees this distance had reached 58.3±1.2 mm tibia in knee flexion at 20°; 57.8±,4 mm - when flexed by 30°; 56.9±1,3 mm - at 45°; 56.8±1,3 mm - at 60° of flexion and 53.0±0,7 mm - at 90°. Conclusion. There are several variants of MPFL anatomical structure, and in most cases it has two bundles oriented to the medial surface of the knee from posterior to anterior and from proximal to distal directions. MPFL has a streak of isometry, as a normal characteristic of each anatomical ligament and this isometry must be followed in MPFL reconstruction in case of recurrent patella dislocation.

коленный сустав, внутренняя бедренно-надколенниковая связка, привычный вывих надколенника, knee, medial patellofemoral ligament, patella instability