part of has skeleton pelvic region of trunk sacral region back of pelvis rump regio sacralis hindquarter pelvic back FMA:24228 sacral part of pelvis posterior part of pelvis Wikipedia:Sacrum SCTID:182344001 A subdivision of an organism along the anterior-posterior axis in the pelvic region immediately posterior to the lumbar region and anterior to the caudal region. Sometimes an intermediate region is defined between the sacral and caudal. croup sacral region of vertebral column subdivision of organism along main body axis