The fabella bone is characterized as a sesamoid that is located in the posterior region of the knee, precisely in the tendon of the lateral head of the gastrocnemius muscle, behind the lateral femoral condyle. During routine physical therapy visits, pain was found in the functional evaluation of the posterior region of the knee during flexion-extension movements of the right knee. A radiograph of the right knee in the lateral plane was requested and the fabela bone was evidenced. Patients with fabella may be asymptomatic. However, here we find a case in which the fabela bone may be associated with pain in the lateral aspect of the knee.
