The natural history of human gait and posture

The human fossil record is one of the most complete for any mammal. A basal ancestral species, Australopithecus afarensis, exhibits a well-preserved postcranium that permits reconstruction of important events in the evolution of our locomotor skeleton. When compared with those of living apes and modern humans, this species provides a number of insights into the origin and design of the modern human frame as well as the selective agencies that have guided its evolution during the past three million years. Evolutionary aspects of the human spine and pelvis are reviewed, including their impact on several clinically relevant aspects of human gait and posture.