Where in the body will you find ball and socket joints?

The shoulder and hip joints are the only ball-and-socket joints in the human body due to the need for great motion at the end of the body’s limbs and the vast numbers of muscles needed to move and support such flexible joints. In the shoulder joint, the spherical head of the humerus (upper arm bone) fits into the glenoid cavity of the scapula (shoulder blade). The glenoid cavity permits the shoulder joint the greatest range of motion in the human body. The muscles of the rotator cuff hold the humerus in place.The hip joint is somewhat less moveable than the shoulder, but is an overall stronger and more stable joint. That is necessary to bear the weight of the body resting on the legs while performing actions such as standing, walking, and running. In the hip joint the rounded, almost spherical head of the femur (thigh bone) fits tightly into the acetabulum, a deep socket in the os coxa (hip bone). The largest muscle in the body is found here: the gluteus maximus. Many tough ligaments and the powerful hip muscles hold the head of the femur in place and resist some of the most powerful strains in the body. The depth of the acetabulum also prevents dislocations of the hip by limiting the movement of the femur in its socket.