Pubic symphysis is an original joint, because its vertical fibro-cartilaginous disc, inserted between the two ‘endplates’ of pubic bones, is reminiscent of a vertebral disc. It must resist compression, tearing, and shearing stresses, and physiological vertical shift can reach 2 mm and rotation 1°. During pregnancy, relaxin induces the resorption of the edges of symphysis, leading to widening of the joint. Structural changes within the disc also increase its mobility. Rectus abdominalis, adductor longus and obliquus externus control those shifts, but the sites of insertions of those muscles around the symphysis are still disputed. The pattern of entanglement of collagen fibers within the disc has been poorly studied. The same hold true for the central cleft, which develops over time, as also observed in some vertebral discs. The biomechanics and motility of symphysis according to sex and anatomic variations should be further studied, as well as the inter-individual changes in joint innervations, to better explain the changing occurrences of pubalgia across the population, either in sports or pregnancy.