The Collaborative International Dictionary
Lumbosacral \Lum`bo*sa"cral\, n. [L. lumbus loin + E. sacral.] (Anat.) Of or pertaining to the loins and sacrum; as, the lumbosacral nerve, a branch of one of the lumber nerves which passes over the sacrum.
Wiktionary
a. Of or pertaining to the lumbar and sacral regions of the back; the small of the back and the back portion of the pelvis.
WordNet
adj. of or relating to or near the small of the back and the back part of the pelvis between the hips
Wikipedia
Usage examples of "lumbosacral".
Scoliosis may be a cervicodorsal, dorsolumbar, or lumbosacral curve, and the inclination of the vertebral column may be to the right or left.
More X-rays revealed sternal rib ends with irregular bony growths, the bone very thin-walled with sharp edges, and there were degenerative changes to the lumbosacral vertebrae, as well.