Subdivision of abdominal segment of trunk which in humans 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[Modified from FMA].
Comment:
overlaps with region sometimes called 'loin'
Synonyms:
exact_synonym:
abdominal back; back of abdomen; dorsum of abdomen; lumbar part of back; lumbar region of back; posterior part of abdomen; regio lumbalis