Lower extremity of femur extended. Where the groove ceases laterally the patellar surface is seen to be continued backward as a semilunar area close to the anterior part of the intercondyloid fossa; this semilunar area articulates with the medial vertical facet of the patella in forced flexion of the knee-joint. The tibial surfaces of the condyles are convex from side to side and from before backward. Each presents a double curve, its posterior segment being an arc of a circle, its anterior, part of a cycloid. Lower extremity of femur The lower extremity of femur (or distal extremity) is the lower end of the
Ball and socket joint the femur (ball) rests in the cup-like acetabulum (socket) of the pelvis, and in the glenohumeral joint of the shoulder, where the rounded head of the humerus (ball) rests in the cup-like glenoid fossa (socket) of the shoulder blade. The shoulder includes a sternoclavicular articulation joint. Ball and socket joint The ball and socket joint (or spheroid joint) is a type of synovial joint in which the ball-shaped surface of one rounded bone fits into the cup-like depression of another bone. The distal bone is capable of motion around an indefinite number of axes, which have one common center. It