Ligaments of the Flexed Knee Joint, Lateral View

Description

Presented in lateral profile with the knee flexed, the distal femur articulates with the proximal tibia at the femorotibial joint while the patella sits anterior to the femoral trochlea at the patellofemoral compartment. Along the lateral margin of the capsule, fibrous reinforcements align from the lateral femoral epicondyle toward the fibular head, with the lateral collateral ligament (fibular collateral ligament) running superficially and the popliteus tendon coursing posterolaterally toward its femoral attachment. Posterior to the joint line, capsular thickening consistent with the oblique popliteal ligament and arcuate complex frames the posterolateral corner, and the patellar ligament continues inferiorly from the patellar apex to the tibial tuberosity. Bone landmarks remain clear. Flexion shifts which stabilizers are taut, so a lateral flexed view is the one you want when teaching why the posterolateral corner resists external rotation and varus, and why injuries there so often accompany anterior cruciate ligament tears. Clinically, the relationship between the fibular collateral ligament, popliteus tendon, and lateral capsule explains positive dial test findings and guides surgical reconstruction planes, while the anterior patellofemoral alignment helps frame lateral patellar instability and the mechanics behind a positive patellar apprehension test. Small structures, big consequences. Use this asset for musculoskeletal anatomy teaching in gross lab and sports medicine blocks, for orthopaedic and radiology atlases covering lateral knee stability, and for operative overviews of lateral approach intervals around the fibular head where the common fibular nerve is at risk. It also fits patient education materials on ligament sprain patterns in pivoting sports. Anatomical accuracy verified by SciePro's Medical Advisory Board.