[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Anatomy](https://durgical.com/en/anatomy/) › [Spine](https://durgical.com/en/anatomy/region/spine/) › Lumbar veins [Cardiovascular system](https://durgical.com/en/anatomy/system/cardiovascular-system/) · [Spine](https://durgical.com/en/anatomy/region/spine/) # Lumbar veins The lumbar veins run with the [lumbar arteries](https://durgical.com/en/anatomy/lumbar-arteries/) and drain blood from the lumbar [spine](https://durgical.com/en/anatomy/region/spine/) and back muscles toward the vena cava. [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=spine&select=lumbar_veins&side=r) Opens in the Durgical app, no sign-up needed. ## What it is Veins running with the lumbar arteries, draining the back and spine into the vena cava and the ascending lumbar veins. ## What it does Drain blood from the lumbar spine and back muscles. ## Key points - The ascending lumbar vein runs up in front of the transverse processes, linking the [common iliac vein](https://durgical.com/en/anatomy/common-iliac-vein/), the lumbar veins and the subcostal vein; it becomes the azygos on the right and the hemiazygos on the left - The left lumbar veins cross behind the aorta to reach the inferior vena cava, so they are longer than the right ones - The left ascending lumbar vein, with the iliolumbar vein, tethers the left common iliac vein and is tied in anterior L4–L5 exposure ## Key facts **Drains** Posterior abdominal wall, lumbar vertebrae, vertebral venous plexuses and back muscles **Into** Inferior vena cava (mainly 3rd and 4th); linked by ascending lumbar veins to azygos (right) and hemiazygos (left) ## Relations **Course** Each runs with its lumbar artery around the waist of a vertebral body, under the [psoas major](https://durgical.com/en/anatomy/psoas-major/), to the [inferior vena cava](https://durgical.com/en/anatomy/inferior-vena-cava/); the ascending lumbar veins join them vertically **In front** Psoas major and the [sympathetic trunk](https://durgical.com/en/anatomy/sympathetic-trunk/); on the left, also the [abdominal aorta](https://durgical.com/en/anatomy/abdominal-aorta/) **Behind** Vertebral bodies and, at the foramina, the connections with the vertebral venous plexuses ## How to find it They cannot be felt. In anterior and lateral approaches they cross the waist of each vertebral body with the lumbar arteries; the left ascending lumbar vein is found at the side of the L5 body, behind the left common iliac vein. ## On imaging Not seen on radiographs. Venous-phase contrast CT shows them curving round the vertebral bodies to the IVC; the left ones cross behind the aorta, and the ascending lumbar vein lies in front of the transverse processes. CT is reviewed before anterior lumbar or retroperitoneal access to spot large or variant veins. Injury shows as a retroperitoneal or psoas haematoma. ## Clinical notes - Avulsion while retracting the great vessels bleeds into the retroperitoneum or the psoas major and is difficult to control - Their valveless connections with the vertebral venous plexuses (Batson) let blood, and tumour cells, move between the [abdomen](https://durgical.com/en/anatomy/region/abdomen/) and the spinal canal with changes in abdominal pressure - When the inferior vena cava is blocked they carry blood through the ascending lumbar veins to the azygos system ## Anatomical variants - A left lumbar vein often drains into the [left renal vein](https://durgical.com/en/anatomy/right-renal-vein/), which matters in left [kidney](https://durgical.com/en/anatomy/kidney/) surgery and in anterior approaches - Their number and endings vary: the upper ones may drain into the ascending lumbar vein rather than the cava ## Test yourself Think of the answer, then tap the question to see it. ## Into which vein do the lumbar veins mainly drain, and which ones usually do so? The inferior vena cava, mainly the 3rd and 4th lumbar veins; the ascending lumbar veins link them to the azygos (right) and hemiazygos (left). ## Why are the left lumbar veins longer than the right ones? They must cross behind the aorta to reach the inferior vena cava, which lies on the right. ## Which vein, tethering the left common iliac vein, is tied during anterior L4–L5 exposure? The left ascending lumbar vein, together with the iliolumbar vein; tying it lets the left common iliac vein be moved safely. ## How do the lumbar veins allow tumour cells to reach the spinal canal? Through valveless connections with the vertebral venous plexuses (Batson): blood and tumour cells shift between abdomen and canal with changes in abdominal pressure. [Add to my cards (4)](https://durgical.app/estudiar/?add=/en/anatomy/lumbar-veins/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** venae lumbales; vena lumbalis ascendens dextra; vena lumbalis ascendens sinistra TA2 4993 **Official Spanish (DeCS)** Venas lumbares **English (TA2)** Lumbar veins ## Related - [Lumbar arteries](https://durgical.com/en/anatomy/lumbar-arteries/) Sources: Terminologia Anatomica (TA2); [Anatomy, Abdomen and Pelvis: Inferior Vena Cava](https://www.ncbi.nlm.nih.gov/books/NBK482353/). ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/anatomy/lumbar-veins/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/lumbar-veins/