Lumbarization is an anatomical variant or anomaly of the development of the spine , in which the first sacral vertebra is partially or completely likened to the last lumbar. Lumbarization is recognized by radiography . Usually lumbarization is not clinically manifested. Currently, instead of the terms "lumbarization" or "sacralization" the term "transitional lumbosacral vertebra" is adopted. See also Sacralization .