regional_part_of Back of trunk Subdivision of back of trunk Abdominal segment of trunk Abdominal segment of male trunk Abdominal segment of female trunk Back of abdomen Abdominal back Dorsum of abdomen FMA:61681 Lumbar part of back Lumbar region Posterior part of abdomen Subdivision of abdomen which is demarcated from the front of the abdomen by the posterior surface of the anterior layer of the thoracolumbar fascia and the anterior surface of the lumbar vertebral column; together with the front of the abdomen, it constitutes the abdomen. Examples: There is only one back of abdomen. fma