Case Report

Fabella Fractures after Total Knee Arthroplasty with Correction of Valgus Malalignment

Figure 1

Posterolateral ligamentous complex of the knee including arcuate ligament, fabellofibular ligament, popliteal-fibular ligament, lateral collateral ligament, and biceps femoris tendon (case courtesy of Dr. Frank Gaillard, http://radiopaedia.org/). The fabella is located in the posterior aspect of the knee where lines of tensile stress intersect [14]. It articulates with the posterior part of the articular surface of the lateral femoral condyle and is embedded in the muscular fibres of the gastrocnemius muscle [14]. Anteriorly the fabella is bordered by the posterior capsule of the knee joint and posteriorly it is situated at the endpoint of the oblique popliteal ligament and the lateral gastrocnemius tendon [14]. In addition, the fabellofibular ligament runs to its distal insertion at the styloid process of the fibular head [14].