Joint locking (medicine) symptom of: Locking of the knee happens during the last stages of extension when a person is standing up. Medial rotation of femur occurs as the space available at the lateral condyle of tibia is being used up by the lateral condyle of femur during extension. Therefore, lateral femoral condyle acted as an axis for medial femoral condyle to rotate backwards. This movement is aided by oblique pull of the ligaments of the knee joint and contraction of the quadriceps muscles. The ligaments are pulled taut when the knee joint is locked in place during standing. When the knee is
Femur the third trochanter varies from 17–72% between ethnic groups and it is frequently reported as more common in females than in males. The lower extremity of the femur (or distal extremity) is larger than the upper extremity. It is somewhat cuboid in form, but its transverse diameter is greater than its antero-posterior (front to back). It consists of two oblong eminences known as the condyles. Anteriorly, the condyles are slightly prominent and are separated by a smooth shallow articular depression called the patellar surface. Posteriorly, they project considerably and a deep notch, the Intercondylar fossa of femur, is present between