As we age the characteristics of the sacroiliac joint change.[4] The joint's surfaces are flat or planar in early life but as we start walking, the sacroiliac joint surfaces develop distinct angular orientations and lose their planar or flat topography.[2] They also develop an elevated ridge along the ilial surface and a depression along the sacral surface.[5] The ridge and corresponding depression, along with the very strong ligaments, increase the sacroiliac joints' stability and makes dislocations very rare. The fossae lumbales laterales ("dimples of Venus") correspond to the superficial topography of the sacroiliac joints.