lumbar veins

例句：

1. 1. The surgeon performed a successful operation on the patient's lumbar veins.
   外科医生成功地为病人的腰椎静脉进行了手术。
2. 2. Lumbar veins are responsible for carrying blood from the lower extremities back to the heart.
   腰椎静脉负责将血液从下肢输送回心脏。
3. 3. During surgery, the surgeon carefully dissected the lumbar veins to avoid damaging them.
   在手术过程中，外科医生小心地解剖了腰椎静脉以避免损伤它们。