The Role of the Popliteofibular Ligament in Stability of the Human Knee

The popliteal tendon has a significant attachment to the fibula, the popliteofibular ligament. The role of this ligament in knee stability has not been determined. In this study we used selective cutting techniques to measure the static contribution of the popliteal tendon attachments to the tibia and the popliteofibular liga ment for stability of the knee. Sectioning of all the posterolateral structures except the popliteal tendon attachments to the tibia or the popliteofibular ligament resulted in increased primary posterior translation, va rus rotation, external rotation, and coupled external rotation. Although statistically significant, these in creases were small. Sectioning of all the posterolateral structures resulted in larger increases in primary pos terior translation, varus rotation, external rotation, and coupled external rotation. Our data indicate that the popliteal tendon attachments to the tibia and the pop liteofibular ligament are important in resisting posterior translation and varus and external rotation. If an iso lated injury to the posterolateral structures occurs, an atomic reconstruction of the major ligaments that re strain posterior translation and varus and external rotation may provide the best functional result. Recon struction for isolated posterolateral instability should include anatomic attachment of the popliteal tendon to the tibia and the popliteofibular ligament.