From the Research
The fat anterior to the psoas muscle below the lower pole of the kidney is not part of the kidney's lymphatic chain. The kidney's lymphatic drainage primarily follows the renal vessels and drains into the lateral aortic (para-aortic) and paracaval lymph nodes. The fat anterior to the psoas muscle below the kidney's lower pole is typically retroperitoneal fat that may contain lymphatic vessels, but these are not specifically part of the kidney's primary lymphatic drainage system. Some studies have investigated the anatomy of the psoas muscle and its relationship to the kidney, such as the case report of a giant psoas muscle lipoma 1, but these do not directly address the lymphatic drainage of the kidney. Other studies have focused on the medial arcuate ligament as a landmark for locating the renal artery during retroperitoneal laparoscopic renal surgery 2, or the identification of the anterior psoas sheath as a landmark for lumbar sympathetic block 3, but these also do not provide information on the lymphatic drainage of the kidney. The kidney's lymphatic vessels emerge from the hilum along with the renal vein and ascend toward the cisterna chyli and thoracic duct. Understanding this anatomical distinction is important for surgical approaches and imaging interpretation in renal pathologies, as metastatic spread from kidney tumors would follow these specific lymphatic pathways rather than involving the fat anterior to the psoas muscle below the kidney. Key points to consider include:
- The kidney's lymphatic drainage is separate from the fat anterior to the psoas muscle below the kidney's lower pole
- The medial arcuate ligament can serve as a landmark for locating the renal artery during surgery 2
- The anterior psoas sheath can be used as a landmark for lumbar sympathetic block 3
- The anatomy of the psoas muscle and its relationship to the kidney can be complex, as seen in cases of horseshoe kidneys 4